RU2808167C1 - Installation and method for obtaining polyalphaolefins - Google Patents

Abstract

FIELD: polyalphaolefins.

SUBSTANCE: invention is related to an installation for production of polyalphaolefins. The installation for producing polyalphaolefins contains a mixing unit, a microchannel reaction unit, a high-pressure separation unit, a low pressure separation unit, a gas circulation unit, a post-processing unit and a pressure control unit, wherein the mixing unit, the microchannel reaction unit, the high pressure separation unit, the separation unit low pressure and gas circulation unit are connected in series. The microchannel reaction unit is provided with a BF3 gas inlet, the mixing unit is equipped with an auxiliary raw material inlet and an olefin raw material inlet, the gas circulation unit is connected to the BF3 gas inlet, the low pressure separation unit is connected to the post-processing unit, the high pressure separation unit, the pressure control unit and the gas circulation unit are connected in series, and optionally the post-processing unit is connected to the mixing unit, where the microchannel reaction unit is one microchannel reactor or a combination of two or more microchannel reactors. Moreover, the microchannel reactor has the following structure and parameters: the reaction channel consists of 2-10000 parallel channels, preferably 2-5000 channels, more preferably 2-500 channels, the operating temperature range is from -70 to 300°C, the permissible maximum reaction pressure does not exceed 20 MPa, the permissible maximum pressure of the heat exchange medium does not exceed 10 MPa; he volume of the liquid channel without mixing inserts is 0.1-20000 L, the volumetric flow rate is 1-50000 L/h. A mixing element that facilitates mixing of the reaction streams is provided in each reaction channel, preferably the microchannel reactor is provided with a main pipe for introducing reaction gas and outlet pipes for distributing the reaction gas into each reaction channel, and the microchannel reactor includes: a housing; a feed zone, a mixing zone, a reaction zone and a collection zone arranged in series and in communication along a first direction in the housing, the housing being provided with a supply pipe in communication with the supply zone and an outlet pipe in communication with the collection zone, and the zone mixing is equipped with a mixing channel running along the first direction; liquid distribution pipe; the liquid distribution pipe extends from the outside of the housing into the mixing channel, the liquid distribution pipe is connected to a liquid distributor at the end of the mixing channel; a supply pipe is connected to the mixing unit and is configured to introduce a mixture of olefin feedstock and auxiliary raw materials, a liquid distribution pipe is connected to the BF3 gas inlet and is configured to introduce the BF3 gas, and an outlet pipe is connected to the high pressure separation unit. The invention is also related to a method for producing polyalphaolefins.

EFFECT: development of a plant and method for producing alpha-olefin oligomers, which are characterized by high conversion, high selectivity, simplicity of the process, low capital investment, safety and environmental friendliness, and also have low kinematic viscosity and high viscosity index.

19 cl, 8 dwg, 13 tbl, 12 ex

Description

Field of technology

The present invention relates to a plant and method for producing polyalphaolefins, in particular to a plant and method for producing polyalphaolefins using a continuous process.

State of the art

Polyalphaolefins are typically produced by the polymerization of one or more linear alpha-olefins through an oligomerization reaction under the influence of catalysts. Hydrogenated polyalphaolefins, obtained by separating and hydrogenating polyalphaolefins, can be used for blending into high quality synthetic base oils. Polyalpha olefin synthetic base oil, also known as PAO synthetic base oil, has excellent properties such as high viscosity index, ultra-low pour point, excellent thermal and oxidative stability and high flash point, so it is widely used. PAO synthetic base oils are classified according to their kinematic viscosities at 100°C. Main products include PAO4, PAO6, PAO8, PAO10, PAO40, PAO100, etc. Of these, low-viscosity PAOs with a kinematic viscosity at 100°C between 4 and 8 cSt are the most widely used, mainly for mixing with various types of high-quality motor oils. The use of low-viscosity PAOs can reduce engine torque loss when cold, while extending oil drain intervals and improving fuel economy.

The traditional process for producing polyalphaolefins generally uses a Lewis acid catalytic system to subject the alpha olefins to an oligomerization reaction, and the reaction will produce polymers with varying degrees of polymerization. Currently, the catalysts used in industry for the production of low-viscosity polyalphaolefins are mainly BF ₃ -(excipient) catalysts. Typical production methods use batch or continuous mixing reactors. In an oligomerization reaction system in which alpha-olefins catalyze BF ₃ -(excipient), the BF ₃ in the gas phase must be completely dispersed and mixed with the excipient and alpha-olefins in the liquid phase, with a portion of it dissolving to form the active cationic catalyst and then initiates the alpha-olefin oligomerization reaction. BF ₃ dissolution and interfacial mass transfer determine the macroscopic reaction rate, conversion, etc. In addition, if the reaction time is too short, olefin conversion is generally low and product yield is low. If the reaction time is too long, the resulting alpha-olefin oligomer may undergo side reactions such as a secondary polymerization reaction, which increases the degree of polymerization, and an isomerization reaction, which causes a decrease in viscosity index.

US4045508A discloses a process for the continuous production of polyalphaolefins, which is characterized by combining a mixing reactor and a tubular reactor to control a multi-stage polymerization process. However, this method leads to a large secondary polymerization reaction of oligomers, and the trimer content is significantly reduced.

Document CN104370675B discloses a process for producing polyalphaolefins in a continuous manner, and the method includes introducing alpha olefins into a continuous transparent microchannel reactor and carrying out a polymerization reaction in the presence of an aluminum compound catalyst and auxiliary agents to produce polyalphaolefins. This method consumes large amounts of catalyst and requires a higher reaction temperature.

On the other hand, after carrying out a reaction using boron trifluoride or a complex thereof as a catalyst, it is often necessary to remove the boron trifluoride or complex thereof from the product. For this reason, it is common to use a neutralizing method with alkaline substances such as aqueous sodium hydroxide and ammonia water, followed by rinsing with water. However, this method will create serious environmental pollution problems, and the catalyst cannot be reused. The resulting alkaline liquid waste, fluoride wastewater and boron wastewater are very difficult to treat. At the same time, the process of washing with water will lead to a large waste of water resources. In addition, due to the tightening of national environmental policies, a large number of polluting industries have been closed, and projects without proper pollution disposal methods cannot be implemented.

To date, many methods have been proposed to remove and cure boron trifluoride, but they all have different limitations.

US Application US4433197A discloses a method of using SiO ₂ particles to adsorb BF ₃ into a polymerization reaction solution at a lower temperature, and then regenerate the BF ₃ by heating at low pressure. US application US2997371A proposes to deposit polyacrylonitrile on the surface of inert particles such as activated carbon and activated alumina and then use it to adsorb BF ₃ ; US Application US5846429A discloses the use of polyacrylonitrile fibers to adsorb BF ₃ and the use of heat after adsorption saturation to release BF ₃ . Chinese patent application CN1289344A discloses a method of using metal fluoride for separating and recovering BF ₃ . First, the metal fluoride and BF ₃ are chemically reacted to form tetrafluoroborate to separate BF ₃ , and then the tetrafluoroborate is decomposed under heating conditions at high temperature to release BF ₃ . US Application US4454366A proposes a method for removing BF ₃ using polyvinyl alcohol and BF ₃ to form a stable complex.

US Patent US6939943B2 discloses a method for extracting BF ₃ using methanol and ethanol, where at low temperature methanol or ethanol is added to the polymerization reaction solution and BF ₃ is extracted into an alcohol phase to separate the BF ₃ .

Chinese patent application CN1217726A discloses an electrodeposition separation method in which an electric field is applied to a polymerization solution to separate a boron trifluoride complex from a polymerization product.

Taking advantage of the instability of the boron trifluoride complex, in US Application No. 3,929,749A, to perform catalyst separation, a heating method is adopted to thermally decompose the complex in the polymerization solution, causing BF ₃ gas to flow out of the solution.

In a reaction using boron trifluoride as one of the catalyst components, it is the complex formed by boron trifluoride and the ligand that performs the catalytic function. These boron trifluoride complexes are usually selected for a specific ligand, and the molar ratio between boron trifluoride and the ligand is also specific. Therefore, if the catalyst is to be recycled and reused, this should be done without changing the coordination situation between boron trifluoride and the ligand, since if the coordination situation is changed, the catalytic activity of the catalyst will be weakened or the catalyst will even be deactivated.

However, regardless of whether this method is an adsorption method using complexation of BF ₃ with an adsorbent, an extraction method using the rule of dissolving like substances into each other, an electrodeposition method using an electric field, or a thermal decomposition method, there are to a certain extent different problems, such as unfavorable factors such as poor separation efficiency, degradation of catalyst structure, and large influence of side reactions, which limit the application in large-scale industrial production.

In addition, the reaction process in the batch reactor reported in the prior art has the disadvantages of large mixing reactor volume, large occupied area, very stringent requirements for control of process parameters, complex process operation, long reaction time, long production period, etc., and although batch stability can be guaranteed, the continuous production method also cannot provide ideal conversion and selectivity, and both methods cannot handle the catalyst in the product well. Thus, there is a need in the art for a plant and process for producing alpha-olefin oligomers that are characterized by high conversion, high selectivity, ease of process, low capital investment, and safety and environmental friendliness.

It should be noted that the information disclosed in the preceding "Background Art" section is intended only to enhance the understanding of the prior art of the present invention and, therefore, may contain information that does not constitute prior art and is already known to one skilled in the art.

The essence of the invention

The present invention provides a plant and method for producing polyalphaolefins.

More specifically, the present invention includes the following aspects.

In a first aspect, the present invention provides a plant for the production of polyalphaolefins.

The installation for producing polyalphaolefins according to the present invention includes a mixing unit 1, a microchannel reaction unit 2, a high-pressure separation unit 3, a low-pressure separation unit 4, a gas circulation unit 5, a post-processing unit 6 and a pressure control unit 7, wherein the mixing unit 1 microchannel reaction unit 2, high pressure separation unit 3, low pressure separation unit 4 and gas circulation unit 5 are connected in series, microchannel reaction unit 2 is equipped with BF ₃ gas inlet 01, mixing unit 1 is equipped with auxiliary raw material inlet 02 and inlet 03 olefin feedstock, the gas circulation unit 5 is connected to the BF ₃ gas inlet 01, the low pressure separation unit 4 is also connected to the post-processing unit 6, and the high pressure separation unit 3, the pressure control unit 7 and the gas circulation unit 5 are also connected in series . Preferably, the mixing unit 1 is additionally provided with a BF ₃ gas inlet. Optionally, the gas circulation unit 5 is connected by a BF ₃ gas inlet provided in the mixing unit 1. Optionally, a post-processing unit 6 is connected to a mixing unit 1 to recycle the BF ₃ auxiliary feedstock complex and unreacted olefin feedstock.

According to the installation of the present invention, the mixing unit 1 is capable of uniformly mixing the flow entering it (the mixing unit 1 is preferably a mixer, more preferably a static mixer and/or a dynamic mixer). The stream entering the mixing unit 1 contains auxiliary raw materials and olefin feedstock and optionally recycled auxiliary feedstock and BF ₃ complex and unreacted olefin feedstock. Preferably, the stream entering the mixing unit 1 may also include BF ₃ gas, so that the auxiliary feedstock, olefin feedstock and BF ₃ gas can be mixed in the mixing unit. Optionally, the mixer has the following structure and parameters: operating temperature is 20-200°C, and the upper limit of operating pressure does not exceed 20 MPa; the mixer is preferably a static mixer, more preferably an enhanced mixing static mixer; the number of mixers can be one or several. When two or more mixers are used, the mixers may be connected in parallel, in series, or in both parallel and series. The mixer may optionally have a heat transfer layer. The mixer may optionally contain filler; The filler in the mixer can be selected from Pall ring, ceramic ball, regular filler, corrugated filler, wire mesh or plastic ring. In the case where the stream entering the mixing unit 1 includes BF ₃ gas, the mixing unit 1 includes a first mixer for mixing any two of the auxiliary raw materials, olefin feedstock and BF ₃ gas, and a second mixer for further mixing the mixture with a third component; more preferably, the mixing unit 1 includes a first mixer for mixing one of the olefin feedstock and BF ₃ gas and an auxiliary feedstock, and a second mixer for further mixing the mixture with another component of the olefin feedstock and BF ₃ gas. For example, the mixing unit 1 includes a first mixer for mixing the olefin feedstock with the auxiliary raw material and a second mixer for mixing the mixture with BF ₃ gas; or the mixing unit 1 comprises a first mixer for mixing the BF ₃ gas with the auxiliary raw material and a second mixer for mixing the mixture with the olefin feedstock; or the mixing unit 1 contains a mixer for mixing simultaneously BF ₃ gas, auxiliary raw materials and olefin feedstock.

The microchannel reaction unit 2 provides a microchannel reaction of BF ₃ gas from the BF ₃ gas inlet 01 and a mixed stream of auxiliary feedstock and olefin feedstock, as well as optional BF ₃ gas from the mixing unit 1; preferably, the microchannel reaction unit 2 provides a microchannel reaction of BF ₃ gas from the BF ₃ gas inlet 01 and a mixed stream of auxiliary feedstock, olefin feedstock and BF ₃ gas from the mixing unit 1. Preferably, the microchannel reaction assembly is a microchannel reactor. The number of microchannel reactors may be one or more, preferably one, two, three, four, five or six. When two or more microchannel reactors are used, the microchannel reactors may be connected in series, in parallel, or in both parallel and series.

The high pressure separation unit 3 ensures gas-liquid separation of the intermediate flow entering it, while the separated gas phase enters the gas circulation unit 5 through the pressure control unit 7, and the separated liquid phase enters the low pressure separation unit 4. The high pressure separation unit 3 is preferably a high pressure separator. The number of high pressure separators can be one or several; preferably one, two, three, four, five or six. When two or more high pressure separators are used, the high pressure separators may be connected in series, in parallel, or in both parallel and series.

The low pressure separation unit 4 ensures gas-liquid separation of the intermediate flow entering it, while the separated gas phase enters the gas circulation unit 5, and the separated liquid phase enters the subsequent processing unit 6. The low pressure separation unit 4 is preferably a low pressure separator. The number of low pressure separators may be one or more, preferably one, two, three, four, five or six. When two or more low pressure separators are used, the low pressure separators may be connected in series, in parallel, or in both parallel and series.

The gas circulation unit 5 ensures the extraction of the BF ₃ gas entering it and the delivery of the extracted BF ₃ gas through the BF ₃ gas inlet 01 to the microchannel reaction unit 2 for reuse. The gas circulation unit 5 may be one or more of a compressor, a gas circulation pump and a vacuum pump. The number of compressors, gas circulation pumps and vacuum pumps can be one or more, so that the gas circulation unit can carry out single-stage or multi-stage circulation. Optionally, the gas circulation unit 5 is connected to a BF ₃ gas inlet provided in the mixing unit 1 for delivering the recovered BF ₃ gas to the mixing unit for mixing with the auxiliary raw material and the olefin feedstock.

The post-processing unit 6 provides post-processing of the incoming stream to produce a polyolefin product. The post-processing unit may be one or more of an adsorption device, an extraction device, a distillation device, a centrifugation device, a sedimentation device, an alkali washing device, and an aqueous washing device. Preferably, the post-processing unit 6 is a sedimentation device or a centrifugation device. The sedimentation device or centrifugation device ensures that the incoming stream is separated into a light liquid phase and a heavy liquid phase, wherein the heavy liquid phase is a complex of auxiliary raw materials and BF ₃ and unreacted olefin feed material, and is optionally returned to the mixing unit 1 to continue to participate in continuous reaction. The light liquid phase is the crude polyolefin product, which can be subjected to further downstream processing.

The pressure control unit can regulate the pressure of the microchannel reaction unit 2 and the high pressure separation unit 3 to promote the smooth development of the microchannel reaction and the smooth flow of gas-liquid separation flow in the high pressure separation unit 3. The pressure control unit 7 may be one or more of a back pressure valve, a throttle valve and a pressure reduction valve. Optionally, the pressure control unit 7 can independently regulate the operating pressure of the microchannel reaction unit 2 and the operating pressure of the high pressure separation unit 3. Optionally, the pressure control unit 7 can adjust the operating pressure of the microchannel reaction unit 2 so that it is the same as the operating pressure of the high pressure separation unit 3.

According to the installation of the present invention, preferably a gas purification unit 8 is provided between the low pressure separation unit 4 and the gas circulation unit 5, and/or a gas purification unit 8 is provided between the pressure control unit 7 and the gas circulation unit 5. Gas purification unit 8 provides drying and/or purification of the BF ₃ gas entering it. The gas purification unit 8 may be one or more of a gas filter, an adsorption dryer, a freeze dryer and a cyclone separator, preferably an adsorption dryer into which a filler may be filled, and the filler may be one or more of anhydrous silica gel calcium sulfate, anhydrous calcium chloride and activated carbon.

In accordance with the installation according to the invention, the microchannel reaction unit 2 is optionally a single microchannel reactor or a combination of two or more microchannel reactors. The microchannel reactor has the following structure and parameters: the reaction channel consists of 2-10000 parallel channels, the operating temperature range is from -70 to 300°C, the permissible maximum reaction pressure does not exceed 20 MPa, the permissible maximum pressure of the heat transfer medium does not exceed 10 MPa; the volume of the liquid channel without mixing inserts is 0.1-20000 l, the volumetric flow rate is 1-50000 l/h. Also preferably, the reaction channel is formed by 2-5000 channels, more preferably 2-500 channels. For example, a reaction channel may consist of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 channels, or etc. In the microchannel reactor of the present invention, each reaction channel may have a cross-sectional area from 1 to 150 mm ² and a length from 50 to 5000 mm. Preferably, each reaction channel is provided with a mixing element that promotes mixing of the reaction streams, and the mixing element is an element well known in the art that can promote mixing of the reaction streams and increase turbulence, and it can be a mixing disk as well as a first a mixing element and a second mixing element according to the present invention. Preferably, the microchannel reactor of the invention is provided with a main pipe for introducing reaction gas and outlet pipes for distributing the reaction gas into each reaction channel.

According to the apparatus of the present invention, the preferred microchannel reactor 2 (hereinafter sometimes also referred to as the preferred microchannel reactor of the present invention) includes:

building 003; a supply zone 023, a mixing zone 008, a reaction zone 009 and a collection zone 024 arranged in series and in communication along a first direction in the housing 003, the housing 003 being provided with a supply pipe 002 in communication with the supply zone 023, and an outlet pipe 001, located in communication with the collection zone 024, and the mixing zone 008 is equipped with a mixing channel 014 running along the first direction;

pipe 017 for liquid distribution; a liquid distribution pipe 017 extends from the outside of the housing 003 into the mixing channel 014, the liquid distribution pipe 017 is connected to a liquid distributor 016 at the end of the mixing channel 014;

a supply pipe 002 is connected to the mixing unit 1 and can be used to introduce a mixture of olefin raw material and auxiliary raw materials, while a liquid distribution pipe 017 is connected to the BF ₃ gas inlet 01 and can be used to introduce BF ₃ gas, and

the outlet pipe 001 is connected to the high pressure separation unit 3.

In the present invention, the first direction is a flow direction, and this direction may be a horizontal direction, an upward direction or the like. The upward direction is preferable, and the upward direction is more preferable.

In the present invention, the mixing zone 008 and the feeding zone 023 may be separated by a first dividing wall 019. The first dividing wall 019 is provided with a plurality of through holes, and each through hole is aligned with the mixing channel 014, so that the mixing zone 008 is in communication with the feeding zone 023.

In one embodiment of the present invention, the liquid distributor 016 is at least a distributor selected from a micropore powder sintered body, a mesoporous foam, a wire mesh, and a microslit or micropore tube.

Preferably, the liquid distributor is a cylindrical powder sintered body with micropores.

In one embodiment of the present invention, the liquid distributor 016 has a cross-sectional area of 0.01-200 cm ² and a length of 1-2000 mm. The mixing channel has a circular cross-section; preferably the mixing channel has a cross-sectional area of 0.05-400 cm ² and a length of 50-5000 mm. In the present invention, the length and cross-sectional area of the mixing channel 014 are both larger than the length and cross-sectional area of the liquid distributor 016.

In one embodiment of the present invention, the mixing zone is provided with 1-100 (preferably 1-50, more preferably 2-10) mixing channels, the liquid distribution pipe 017 includes a main pipe extending from the outside of the housing to the supply zone, and branch pipes extending from supply zones into each mixing channel 014, with liquid distributors 016 connected to the ends of the outlet pipes.

In one embodiment of the present invention, in the mixing channel 014, the first mixing element 015 is located downstream of the liquid distributor 016.

In one embodiment of the present invention, the first mixing element 015 is provided with a main flow portion and a waste flow portion that are alternately arranged and in communication along the first direction, and the main flow portion is provided with one main flow passage and the waste flow portion is provided with a plurality of exhaust flow passages. Preferably, a collection cavity in communication with the plurality of bleed flow passages is located downstream of the bleed flow portion. The first mixing element may be formed by splicing a plurality of plate elements (the number may be 2-100, preferably 2-50, more preferably 10-30, thickness is approximately 0.2-10 mm) located along the first direction, and on each plate The element is formed with structures such as holes and cavities that correspond to the main flow passage 0001, the exhaust flow passage 0002 and the collection cavity 0003, which is convenient for processing and production.

In one embodiment of the present invention, the mixing zone may include a first heat exchange cavity 013 located in the housing, wherein the mixing channel is located in the first heat exchange cavity, and the housing is provided with a first heat exchange medium inlet 004 and a first heat exchange medium outlet 0005, which are in communication with the first heat exchange cavity.

In one embodiment of the present invention, the volumetric ratio of the first heat exchange cavity to the mixing channel is 2-50; preferably the volume ratio of the first heat exchange cavity to the mixing channel is 5-30. In the mixing zone 008, the mixing channel 014 and the first heat exchange cavity 013 are isolated from each other and are not in communication with each other, but heat transfer between them can be ensured, and pipe fittings with good thermal conductivity can be used in the mixing channel 014.

In one embodiment of the present invention, a transition zone 020 is provided between the mixing zone and the reaction zone, wherein the transition zone is provided with a stabilizing channel 021 of constant cross-section and a diffusion channel 022 of gradually increasing cross-section, which are located and in communication along the first direction, the stabilizing the channel is in communication with the mixing channel, and the diffusion channel is in communication with the reaction zone.

In one embodiment of the present invention, the outlet pipe 018 extending to the outside of the housing is connected to the stabilizing channel.

In one embodiment of the present invention, the diffusion channel is provided with a diffusion plate with cells or slits.

In one embodiment of the present invention, the two ends of the transition zone 020 are respectively provided with partition walls with through holes so that they are isolated from the mixing zone 008 (mainly the first heat exchange cavity 013) and the reaction zone 009 (mainly the second heat exchange cavity 012) and connected to each mixing channel 014 and each reaction channel 010 through each through hole on each partition wall, and the diffusion channel 022 and the stabilizing channel 021 may be pipe fittings provided between the two partition walls.

In one embodiment of the present invention, the reaction zone is provided with a plurality of parallel reaction channels extending along a first direction and in communication with the mixing channel through a transition zone provided with a stabilizing channel 021 and a diffusion channel 022. The reaction channel has a cross section of at least the following: one of round, rectangular and triangular shapes. The number of reaction channels is, for example, 2-10000 channels, preferably 2-5000 channels, and more preferably 2-500 channels.

In one embodiment of the present invention, the reaction channel is provided with a second mixing element, and the second mixing element includes a support bar extending along the first direction, and a toothed element connected to the support bar and extending across the support bar; the toothed element has at least one of triangular, arcuate, wavy and spiral shapes. Preferably, the gear element has a triangular shape, and on one side of the triangle adjacent to the support bar, one corner is connected to the support bar and the other corner is spaced from the support bar by 0.01-20 mm.

In one embodiment of the present invention, each of the reaction channels is independently provided with a plurality of second mixing elements (the number may be 2-100, preferably 2-50, more preferably 10-30), which are stacked on top of each other at intervals, and the toothed elements of the second mixing element are staggered relative to each other.

Preferably, the cross-section of the reaction channel is rectangular and the toothed elements extend between a set of opposite sides of the rectangle.

In one embodiment of the present invention, the reaction channel has a cross-sectional area of 1-150 mm ² and a length of 50-5000 mm, the minimum distance between the reaction channels is 1-50 mm, and the second mixing element has a thickness of 0.1-3 mm, wherein the distance between adjacent gear elements is 1-50 mm; preferably the reaction channel has a length of 100-3000 mm and the minimum gap between the reaction channels is 3-30 mm, the second mixing element has a thickness of 0.2-2 mm, and the gap between adjacent toothed elements is 1.5-20 mm.

In one embodiment of the present invention, the reaction zone may be provided with a second heat exchange cavity 012 located in the housing, wherein the reaction channel is located in the second heat exchange cavity, the housing is provided with a second heat exchange medium inlet 006 and a second heat exchange medium outlet 007, which are in communication with second heat exchange cavity.

In one embodiment of the present invention, the volumetric ratio of the second heat exchange cavity to the reaction channel is 2-50; preferably the volumetric ratio of the second heat exchange cavity to the reaction channel is 5-30.

In one embodiment of the present invention, the second heat exchange cavity 012 may advantageously be formed by the housing 003, and at the two ends, respectively, there are a second dividing wall 025 between the reaction zone 009 and the collection zone 024 and a dividing wall between the reaction zone 009 and the transition zone 020.

The polyalphaolefin production apparatus of the present invention can be used to synthesize polyalphaolefin synthetic oil in a continuous manner and has the advantages of high reaction speed, high reaction conversion and good product selectivity.

A polyalphaolefin production plant using the preferred microchannel reactor of the present invention can continuously and efficiently mix the reaction system, maintain fluid flow in a piston-like manner, ensure that the residence time of the reaction fluid is as constant as possible, and also avoid selectivity for undesirable substances. products due to the distribution of residence time.

In a second aspect, the present invention provides a method for producing polyalphaolefins.

The method for producing polyalphaolefins of the present invention includes: a mixed stream obtained after mixing the olefin raw material and auxiliary raw materials in a mixing unit, and BF ₃ gas are each independently passed into a microchannel reaction unit; the intermediate stream formed after the polymerization reaction in the microchannel reaction unit is passed into the high-pressure separation unit, wherein the intermediate material undergoes a first gas-liquid separation in the high-pressure separation unit, the separated liquid phase enters the low-pressure separation unit, and a second gas-liquid separation occurs in the unit low pressure separations; the liquid phase separated from the low pressure separation unit enters the post-processing unit, and the polyolefin product is obtained after processing in the post-processing unit; The gas phases separated from the high pressure separation unit and the low pressure separation unit (BF ₃ gas) enter the gas circulation unit, and the BF ₃ gas is recovered for reuse. Preferably, the BF ₃ gas is also supplied to the mixing unit, so that the BF ₃ gas, the olefin feedstock and the auxiliary feedstock are mixed in the mixing unit, and then the mixed stream and the BF ₃ gas are each independently supplied to the microchannel reaction unit. Optionally, the heavy liquid phase containing the auxiliary feedstock complex and BF ₃ and unreacted olefin feedstock obtained from the post-processing unit is recycled to the mixing unit.

In one embodiment of the present invention, in the case of supplying BF ₃ gas to the mixing unit, the mixing order of the BF ₃ gas, the olefin raw material and the auxiliary raw material is not particularly limited, and the mixing method can be as follows: any two of the BF ₃ gas can be mixed , olefin starting material and auxiliary raw material and then mixed with the third component, or BF ₃ gas, olefin starting material and auxiliary raw material can be mixed simultaneously. For example, BF ₃ gas and auxiliary feedstock may be complexed and then mixed with an olefin feedstock, or the auxiliary feedstock and olefin feedstock may be mixed and then mixed with BF ₃ gas, or BF ₃ gas, olefin feedstock material and auxiliary raw materials can be mixed at the same time.

In one embodiment of the present invention, the olefin in the olefin feedstock is one or more C ₃ -C ₂₀ alpha olefins, preferably one or more C ₅ -C ₁₅ alpha olefins, more preferably one or more C ₇ -C ₁₄ -alpha-olefins. For example, the olefin may be olefins commonly used in the production of PAO synthetic base oils, such as nonene and decene.

In one embodiment of the present invention, the olefin feedstock may also contain a C ₅ -C ₂₀ alkane and/or a C ₁ -C ₂₀ oxygen-containing compound as a solvent. Relative to the total weight of the olefin feedstock, the mass fraction of C ₅ -C ₂₀ alkane may be 0-80%, preferably 0.5-50%, most preferably 1-30%. Relative to the total weight of the olefin feedstock, the mass fraction of the C ₁ -C ₂₀ oxygen-containing compound may be 0-20%, preferably 0-10%, most preferably 0.001-5%. The C ₅ -C ₂₀ -alkane may be one or more of n-alkane, isoalkane and cycloalkane; The C ₁ -C ₂₀ oxygen-containing compound may be one or more of an n-alkanol, an isoalcohol, and a ketone. The Fischer-Tropsch olefin feedstock can be used as a mixture of a C ₃ -C ₂₀ alpha-olefin, a C ₅ -C ₂₀ alkane and a C ₁ -C ₂₀ oxygen-containing compound (ie, as an olefin feedstock).

In one embodiment of the present invention, the auxiliary raw material may be a commonly used auxiliary raw material that can be used as a BF ₃ electron donor, and may be one or more of an alcohol having 1-20 carbon atoms, an ether having a number of carbon atoms of 1-20, an aldehyde having a number of carbon atoms of 1-20, a ketone having a number of carbon atoms of 1-20, an ester having a number of carbon atoms of 1-30, a carboxylic acid having a number of carbon atoms of 1-20, and phenol having a number of carbon atoms of 1-20; preferably an alcohol having 1-10 carbon atoms, more preferably an alcohol having 3-5 carbon atoms, for example one or more of n-propanol, isopropanol, n-butanol, isobutanol, n-pentanol and isopentanol .

According to the method of the present invention, the mixing unit is capable of uniformly mixing the flow entering it, and is preferably a mixer, more preferably a static mixer and/or a dynamic mixer. The stream entering the mixing unit contains auxiliary feedstock and olefin feedstock, as well as optionally recycled auxiliary feedstock and BF ₃ complex and unreacted olefin feedstock. Preferably, the stream entering the mixing unit may also include BF ₃ gas, so that the auxiliary feedstock, olefin feedstock and BF ₃ gas can be mixed in the mixing unit. In this case, as stated above, the order of mixing the BF ₃ gas, the olefin raw material and the auxiliary raw material in the mixing unit is not particularly limited. The mixing unit is preferably a mixer, and the mixer preferably has the following structure and parameters: the operating temperature is 20-200°C, and the upper limit of the operating pressure is not more than 20 MPa; the mixer is preferably a static mixer, more preferably an enhanced mixing static mixer. The number of mixers can be one or several. When two or more mixers are used, the mixers may be connected in parallel, in series, or in both parallel and series. The mixer may optionally have a heat transfer layer. The mixer may optionally contain filler. The filler in the mixer can be selected from Pall ring, ceramic ball, regular filler, corrugated filler, wire mesh or plastic ring. In the case where the stream entering the mixing unit includes BF ₃ gas, the mixing unit includes a mixer for mixing any two of the auxiliary raw materials, olefin feedstock and BF ₃ gas and a mixer for further mixing the mixture with a third component; more preferably, the mixing unit includes a mixer for mixing one of the olefin feedstock and BF ₃ gas and an auxiliary feedstock and a mixer for further mixing the mixture with another component of the olefin feedstock and BF ₃ gas. For example, the mixing unit includes a mixer for mixing the olefin feedstock and auxiliary raw materials and a mixer for mixing the mixture and BF ₃ gas; or the mixing unit 1 contains a mixer for mixing BF ₃ gas and auxiliary raw materials and a mixer for mixing the mixture and olefin feedstock; or the mixing unit contains a mixer for mixing simultaneously BF ₃ gas, auxiliary raw materials and olefin feedstock.

The microchannel reaction unit provides a microchannel reaction of a mixed stream of BF ₃ gas, auxiliary feedstock and olefin feedstock. Preferably, the microchannel reaction assembly provides microchannel reaction of BF ₃ gas from the BF ₃ gas inlet and a mixed stream of auxiliary feedstock, olefin feedstock, and optional BF ₃ from the mixing assembly. Preferably, the microchannel reaction assembly is a microchannel reactor. The number of microchannel reactors may be one or more, preferably one, two, three, four, five or six. When two or more microchannel reactors are used, the microchannel reactors may be connected in series, in parallel, or in both parallel and series. Any of the microchannel reactors that are described in the first aspect above may be used in a microchannel reaction assembly. The microchannel reactor preferably has the following structure and parameters: the reaction channel consists of 2-10000 parallel channels, the operating temperature range is from -70 to 300°C, the permissible maximum reaction pressure does not exceed 20 MPa, the permissible maximum pressure of the heat exchange medium does not exceed 10 MPa; the volume of the liquid channel without mixing inserts is 0.1-20000 l, the volumetric flow rate is 1-50000 l/h. Also preferably, the reaction channel is formed by 2-5000 channels, more preferably 2-500 channels. For example, a reaction channel may consist of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 channels, or etc. In the microchannel reactor of the present invention, each reaction channel may have a cross-sectional area from 1 to 150 mm ² and a length from 50 to 5000 mm. Preferably, each reaction channel is provided with a mixing element that promotes mixing of the reaction streams, and the mixing element is an element well known in the art that can promote mixing of the reaction streams and increase turbulence, and it can be a mixing disk as well as a first a mixing element and a second mixing element according to the invention. Preferably, the microchannel reactor of the invention is provided with a main pipe for introducing reaction gas and outlet pipes for distributing the reaction gas into each reaction channel.

The high-pressure separation unit ensures gas-liquid separation of the intermediate flow entering it; the separated gas phase enters the gas circulation unit through the pressure control unit, and the separated liquid phase enters the low pressure separation unit. The high pressure separation unit is preferably a high pressure separator. The number of high pressure separators may be one or more, preferably one, two, three, four, five or six. When two or more high pressure separators are used, the high pressure separators may be connected in series, in parallel, or in both parallel and series.

The low pressure separation unit ensures gas-liquid separation of the intermediate flow entering it; the separated gas phase enters the gas circulation unit, and the separated liquid phase enters the subsequent processing unit. The low pressure separation unit is preferably a low pressure separator. The number of low pressure separators may be one or more, preferably one, two, three, four, five or six. When two or more low pressure separators are used, the low pressure separators may be connected in series, in parallel, or in both parallel and series.

The gas circulation unit ensures the extraction of the BF ₃ gas entering it and the delivery of the extracted BF ₃ gas to the microchannel reaction unit for reuse. The gas circulation unit may be one or more of a compressor, a gas circulation pump, and a vacuum pump. The number of compressors, gas circulation pumps and vacuum pumps can be one or more, so that the gas circulation unit can carry out single-stage or multi-stage circulation. Optionally, the gas circulation unit delivers the recovered BF ₃ gas to the mixing unit for mixing with the auxiliary feedstock and olefin feedstock.

The post-processing unit provides post-processing of the incoming stream to produce a polyolefin product. The post-processing unit is preferably one or more of an adsorption device, an extraction device, a distillation device, a centrifugation device, a sedimentation device, an alkali washing device and an aqueous washing device. Preferably, the heavy liquid phase containing the auxiliary feedstock complex and BF ₃ and the unreacted olefin feedstock obtained from the post-processing unit is returned to the mixing unit to continue to participate in the continuous reaction.

The pressure control unit can regulate the pressure of the microchannel reaction unit and the high-pressure separation unit to promote the smooth development of the microchannel reaction and the smooth flow of gas-liquid separation flows in the high-pressure separation unit. The pressure control unit may be one or more of a back pressure valve, a throttle valve and a pressure reducing valve. Optionally, the pressure control unit can independently regulate the operating pressure of the microchannel reaction unit and the operating pressure of the high pressure separation unit. Optionally, the pressure control unit can adjust the operating pressure of the microchannel reaction unit so that it is the same as the operating pressure of the high pressure separation unit.

In one embodiment of the present invention, in accordance with the method of the invention, the rate of entry of the olefin feedstock into the mixing unit is 10-5000 L/hour, preferably 20-4000 L/hour, more preferably 40-2500 L/hour. The rate of entry of auxiliary raw materials into the mixing unit is 0.01-1000 l/hour, preferably 0.1-800 l/hour, more preferably 0.2-500 l/hour. The gas flow rate for the BF ₃ gas entering the microchannel reaction unit (including the initially introduced BF ₃ gas and optionally recirculated BF ₃ gas) is 5-200,000 l/h, preferably 50-100,000 l/h, more preferably 100- 50000 l/hour. In general, the gas flow rate of BF ₃ gas entering the microchannel reaction unit is controlled to be constant or within a numerical range, and the amount of BF ₃ gas initially introduced can be adjusted according to the amount of BF recycled ₃ -gas as long as the total quantity of the two is a constant value or is within a numerical range. In the case of additional supply of BF ₃ gas to the mixing unit, the speed of BF ₃ gas entering the mixing unit is 4-180000 l/hour, preferably 45-90000 l/hour, more preferably 90-45000 l/hour.

In one embodiment of the present invention, in accordance with the method of the invention, preferably the reaction temperature in the microchannel reaction unit is 0-120°C, preferably 10-80°C, more preferably 20-60°C. The reaction pressure in the microchannel reaction unit is 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa. The residence time of the olefin feedstock in the microchannel reaction unit is 1-3600 seconds, preferably 10-1800 seconds, more preferably 15-1000 seconds. In the microchannel reaction unit, the mass ratio of (auxiliary feedstock):(olefin feedstock):(total BF ₃ gas) is 1:1-1000:1-500 (preferably 1:1-500:1-200, most preferably 1 :10-250:1.5-100). When the microchannel reaction unit is the above-mentioned microchannel reactor, the mass ratio of (auxiliary raw materials):(olefin feedstock):(total amount of BF ₃ gas) refers to the mass ratio of the feedstocks when all the feedstocks are fed into the microchannel reactor, that is, this may represent the proportion of reaction feeds in the stream immediately downstream of the liquid distributor.

In one embodiment of the present invention, in accordance with the method of the invention, the high pressure separation unit is preferably a high pressure separator. The pressure of the high pressure separator may be 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa. The temperature of the high pressure separator may be 0-120°C, preferably 10-80°C, more preferably 20-60°C. The volume of the high pressure separator can be 0.1-20000 L, preferably 0.2-2000 L.

In one embodiment of the present invention, the low pressure separation unit is preferably a low pressure separator. The low pressure separator pressure may be -0.1 to 1 MPa, preferably -0.1 to 0.9 MPa, more preferably -0.1 to 0.1 MPa. The temperature of the low pressure separator may be 0-120°C, preferably 10-80°C, more preferably 20-60°C. The volume of the low pressure separator can be 0.1-20000 l, preferably 0.2-2000 l.

In one embodiment of the present invention, the pressure of the recycled BF ₃ gas through the gas circulation unit may be 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa.

In one embodiment of the present invention, the pressure of the pressure control unit is 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa.

In one embodiment of the present invention, in accordance with the method of the invention, the post-processing method used in the post-processing unit may be post-processing methods well known to those skilled in the art, and, for example, may be one or more of the following: adsorption, extraction, distillation, centrifugation, sedimentation, alkaline washing and aqueous washing. Preferably, the post-processing method is sedimentation or centrifugation. Sedimentation or centrifugation provides separation of the stream entering the downstream processing unit into a light liquid phase and a heavy liquid phase, the heavy liquid phase being a complex of auxiliary raw materials and BF ₃ and unreacted olefin feed material and optionally returned to the mixing unit to continue to participate in continuous reaction. The light liquid phase is the crude polyolefin product, which can be subjected to further downstream processing.

In one embodiment of the present invention, according to the method of the invention, preferably a gas purification unit is provided between the low pressure separation unit and the gas circulation unit, and/or a gas purification unit is provided between the pressure control unit and the gas circulation unit. The gas purification unit provides drying and/or purification of the BF ₃ gas entering it. The gas purification unit may be one or more of a gas filter, an adsorption dryer, a freeze dryer and a cyclone separator, preferably an adsorption dryer into which a filler may be filled, and the filler may be one or more of silica gel, anhydrous calcium sulfate, anhydrous calcium chloride and activated carbon.

In one embodiment of the present invention, in accordance with the method according to the invention, in the case where BF ₃ gas is also mixed in the mixing unit in addition to the olefin feedstock and auxiliary raw materials, based on the total mass of all BF ₃ in the microchannel reaction unit, the mass ratio of BF ₃ - of gas, which directly enters the microchannel reaction unit, to the BF ₃ gas, which is mixed in the mixing unit, is 100-10: 0-90.

In accordance with the method of the present invention, it is also preferable for the resulting polyolefin product to be subjected to fractionation, hydrogenation and optional blending operations to obtain a synthetic oil that matches the viscosity grade.

The method of the present invention has the advantages of high polymerization reaction rate, high reaction conversion and good product selectivity, and is suitable for large-scale industrial production.

In a third aspect, the present invention provides a method for producing polyalphaolefins using any of the plants described in the first aspect.

A method for producing polyalphaolefins using any of the plants described in the first aspect in accordance with the present invention includes:

the mixed stream obtained after mixing the olefin raw material and the auxiliary raw material in the mixing unit 1, and the BF ₃ gas are each independently passed into the microchannel reaction unit 2; the intermediate stream formed after the polymerization reaction in the microchannel reaction unit 2 is passed into the high pressure separation unit 3, the intermediate flow is subjected to a first gas-liquid separation in the high pressure separation unit 3; the separated liquid phase enters the low pressure separation unit 4, and the second gas-liquid separation occurs in the low pressure separation unit 4; the liquid phase separated from the low pressure separation unit 4 enters the post-processing unit 6, and the polyolefin product is obtained after processing in the post-processing unit; The gas phases separated from the high pressure separation unit 3 and the low pressure separation unit 4 (BF ₃ -gas) enter the gas circulation unit 5, and the BF ₃ -gas is recovered for reuse. Preferably, the BF ₃ gas is further supplied to the mixing unit 1, so that the BF ₃ gas, the olefin feedstock and the auxiliary raw material are mixed in the mixing unit 1, and then the mixed stream and the BF ₃ gas are each independently supplied to the microchannel reaction unit 2. Optionally the heavy liquid phase containing the complex of auxiliary raw materials and BF ₃ and unreacted olefin feedstock obtained after processing in the after-treatment unit 6 is recycled to the mixing unit 1.

In one embodiment of the present invention, the olefin in the olefin feedstock is one or more C ₃ -C ₂₀ alpha olefins, preferably one or more C ₅ -C ₁₅ alpha olefins, more preferably one or more from among C ₇ -C ₁₄ alpha-olefins. For example, the olefin may be olefins commonly used in the production of PAO synthetic base oils, such as nonene and decene.

In one embodiment of the invention, the olefin feedstock may also contain a C ₅ -C ₂₀ alkane and/or a C ₁ -C ₂₀ oxygen-containing compound as a solvent. Relative to the total weight of the olefin feedstock, the mass fraction of C ₅ -C ₂₀ alkane may be 0-80%, preferably 0.5-50%, most preferably 1-30%. Relative to the total weight of the olefin feedstock, the mass fraction of the C ₁ -C ₂₀ oxygen-containing compound may be 0-20%, preferably 0-10%, most preferably 0.001-5%. The C ₅ -C ₂₀ -alkane may be one or more of n-alkane, isoalkane and cycloalkane; The C ₁ -C ₂₀ oxygen-containing compound may be one or more of an n-alkanol, an isoalcohol, and a ketone. The Fischer-Tropsch olefin feedstock can be used as a mixture of a C ₃ -C ₂₀ alpha-olefin, a C ₅ -C ₂₀ alkane and a C ₁ -C ₂₀ oxygen-containing compound (ie, as an olefin feedstock).

In one embodiment of the invention, the auxiliary raw material may be a commonly used auxiliary raw material that can be used as a BF ₃ electron donor, and may be one or more of an alcohol having 1-20 carbon atoms, an ether having a number of carbon atoms of 1-20, an aldehyde having a number of carbon atoms of 1-20, a ketone having a number of carbon atoms of 1-20, an ester having a number of carbon atoms of 1-30, a carboxylic acid having a number of carbon atoms of 1-20, and phenol having 1-20 carbon atoms, preferably from an alcohol having 1-10 carbon atoms, more preferably an alcohol having 3-5 carbon atoms, for example one or more of n-propanol, isopropanol, n -butanol, isobutanol, n-pentanol and isopentanol.

According to the method of the present invention, the flow rate of the olefin feedstock into the mixing unit 1 is 10-5000 L/hour, preferably 20-4000 L/hour, more preferably 40-2500 L/hour. The rate of entry of auxiliary raw materials into the mixing unit 1 is 0.01-1000 l/hour, preferably 0.1-800 l/hour, more preferably 0.2-500 l/hour. The gas supply rate for the BF ₃ gas entering the microchannel reaction unit 2 (including the initially introduced BF ₃ gas and the recycled BF ₃ gas) is 5-200,000 l/h, preferably 50-100,000 l/h, more preferably 100 -50000 l/hour. In general, the gas flow rate of BF ₃ gas entering the microchannel reaction unit 2 is controlled to be constant or within a numerical range, and the amount of BF ₃ gas initially introduced can be adjusted according to the amount of recycled BF ₃ gas as long as the total amount of the two is a constant value or within a numerical range. In the case of additional supply of BF ₃ gas to the mixing unit 1, the speed of the BF ₃ gas entering the mixing unit 1 is 4-180000 l/hour, preferably 45-90000 l/hour, more preferably 90-45000 l/hour.

According to the method of the invention, preferably the reaction temperature in the microchannel reaction unit 2 is 0-120°C, preferably 10-80°C, more preferably 20-60°C. The reaction pressure in the microchannel reaction unit 2 is 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa. The residence time of the olefin feed material in the microchannel reaction unit 2 is 1-3600 seconds, preferably 10-1800 seconds, more preferably 15-1000 seconds. In the microchannel reaction unit 2, the mass ratio of (auxiliary feedstock):(olefin feedstock):(total BF ₃ gas) is 1:1-1000:1-500 (preferably 1:1-500:1-200, most preferably 1:10-250:1.5-100). When the microchannel reaction unit 2 is the above-mentioned microchannel reactor, the mass ratio of (auxiliary raw materials):(olefin feedstock):(total amount of BF ₃ gas) refers to the mass ratio of the feedstocks when all the feedstocks are supplied to the microchannel reactor, that is , this may represent the proportion of the reaction feeds in the stream immediately downstream of the liquid distributor.

According to the method of the invention, the high pressure separating unit 3 is preferably a high pressure separator. The pressure of the high pressure separator may be 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa. The temperature of the high pressure separator may be 0-120°C, preferably 10-80°C, more preferably 20-60°C. The volume of the high pressure separator can be 0.1-20000 l, preferably 0.2-2000 l.

The low pressure separation unit 4 is preferably a low pressure separator. The low pressure separation unit 4 is preferably a low pressure separator. The low pressure separator pressure may be -0.1 to 1 MPa, preferably -0.1 to 0.9 MPa, more preferably -0.1 to 0.1 MPa. The temperature of the low pressure separator may be 0-120°C, preferably 10-80°C, more preferably 20-60°C. The volume of the low pressure separator can be 0.1-20000 l, preferably 0.2-2000 l.

The pressure of the recirculated BF ₃ gas through the gas circulation unit 5 can be 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa.

The pressure of the pressure control unit 7 can be 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa.

The method of the present invention has the advantages of high polymerization reaction rate, high reaction conversion and good product selectivity, and is suitable for large-scale industrial production.

Brief description of drawings

FIG. 1 is a schematic diagram of an apparatus according to the present invention.

FIG. 2 is a schematic diagram of a preferred setup according to the present invention.

FIG. 3 is a schematic diagram of a preferred setup according to the present invention.

FIG. 4 is a schematic diagram of a preferred microchannel reactor of the present invention.

FIG. 5 is a cross-sectional view of a first mixing element in accordance with an embodiment of the present invention.

FIG. 6 shows a structural representation of a second mixing element in accordance with an embodiment of the present invention.

FIG. 7 shows a structural representation for stacking a plurality of second mixing elements in accordance with an embodiment of the present invention.

FIG. 8 is a schematic diagram of a comparative installation according to the present invention.

Description of item numbers

1: Mixing unit (preferably mixer)

2: Microchannel reaction unit (preferably microchannel reactor)

3: High pressure separation unit (preferably high pressure separator)

4: Low pressure separation unit (preferably low pressure separator)

5: Gas circulation unit

6: Post-processing unit

7: Pressure control unit

8: Gas cleaning unit

01: BF ₃ gas inlet

02: Auxiliary raw material inlet

03: Olefin feedstock inlet

04-09: Pipelines

001: Exhaust pipe

002: Supply pipe

003: Housing

004: First heat exchange medium inlet

005: First outlet of heat exchange medium

006: Second heat exchange medium inlet

007: Second outlet of heat exchange medium

008: Mixing zone

009: Reaction zone

010: Reaction channel

011: Second mixing element

012: Second heat exchange cavity

013: First heat exchange cavity

014: Mixing channel

015: First mixing element

016: Fluid distributor

017: Liquid distribution pipe

018: Exhaust pipe

019: First dividing wall

020: Transition Zone

021: Stabilizing channel

022: Diffusion channel

023: Feed area

024: Collection area

025: Second dividing wall

0001: Main stream pass

0002: Diversion flow passage

0003: Collection cavity

0004: Support bar

0005: Toothed element

Detailed description

The present invention is described below further by way of examples and in conjunction with the accompanying drawings.

It should be noted that in some examples, the polyalphaolefin production plant can carry out continuous production as long as the temperature and pressure of the microchannel reaction unit can be controlled, so the process parameters and process conditions for all operating units in the plant of the present invention are not listed or need not be listed.

FIG. 1 is a schematic diagram of a plant for producing polyalphaolefins according to the present invention, the plant including a mixing unit 1, a microchannel reaction unit 2, a high pressure separation unit 3, a low pressure separation unit 4, a gas circulation unit 5, a post-processing unit 6 and a unit 7 pressure regulation; mixing unit 1, microchannel reaction unit 2, high pressure separation unit 3, low pressure separation unit 4 and gas circulation unit 5 are connected in series, microchannel reaction unit 2 is equipped with a BF ₃ -gas inlet 01, mixing unit 1 is equipped with an auxiliary raw material inlet 02 and the olefin feedstock inlet 03, the gas circulation unit 5 is connected by the BF ₃ -gas inlet 01, the low pressure separation unit 4 is also connected to the post-processing unit 6, the high pressure separation unit 3, the pressure control unit 7 and the gas circulation unit 5 are also connected in series.

FIG. 2 is a schematic view of a plant for producing polyalphaolefins according to the present invention, which is based on the plant in FIG. 1 by placing a common gas purification unit 8 between the pressure control unit 7 and the gas circulation unit 5 and between the low pressure separation unit 4 and the gas circulation unit 5.

FIG. 3 is a schematic diagram of a plant for producing polyalphaolefins in accordance with the invention, which differs from the plant in FIG. 2 in that the post-processing unit 6 is connected to the mixing unit 1. In the above figure, the post-processing unit 6 is a sedimentation device or a centrifugation device; the sedimentation device or centrifugation device ensures that the incoming stream is separated into a light liquid phase and a heavy liquid phase, and the heavy liquid phase (containing the auxiliary raw material complex and BF ₃ and unreacted olefin feed material) is returned to the mixing unit 1 to continue the continuous reaction.

The microchannel reaction unit 2 of the present invention is preferably the microchannel reactor shown in FIG. 4.

A preferred microchannel reactor of the present invention includes:

building 003; a supply zone 023, a mixing zone 008, a reaction zone 009 and a collection zone 024 are arranged in series and are in communication along a first direction in the housing 003, and the housing 003 is provided with a supply pipe 002 in communication with the supply zone 023, and an outlet pipe 001 located in communication with the collection zone 024, and the mixing zone 008 is equipped with a mixing channel 014 running along the first direction;

a liquid distribution pipe 017, wherein the liquid distribution pipe 017 extends from the outside of the housing 003 into the mixing channel 014, the liquid distribution pipe 017 is connected to the liquid distributor 016 at the end of the mixing channel 014.

The housing 003 is the main container for housing the reactant and product, and the supply zone 023, the mixing zone 008, the reaction zone 009 and the collection zone 024 are different zones of the interior of the housing 003 (all of which can accommodate flow), and these zones are located in a straight line line so that the reactant (and product) moves in a straight line. In the present invention, the flow direction of the flow is called the first direction. Preferably, as shown in FIG. 4, the housing 003 is positioned such that the first direction is an upward direction, and the feeding zone 023, mixing zone 008, reaction zone 009 and collection zone 024 are arranged in the bottom-up direction.

The first group of reaction stream (mixed stream from the mixing unit 1) can be supplied to the supply zone 023 through the supply pipe 002 on the body 003, and the supply zone 023 has a relatively large cavity and can act as a storage for the first group of reaction stream, wherein the first group of reaction stream flow in the feed zone 023 can flow into the adjacent mixing zone 008, that is, into the mixing channel 014. The liquid distribution pipe 017 is connected to the BF ₃ gas inlet, therefore, the introduction of a second group of reaction stream (supplied separately BF ₃ catalyst) can be passed into the mixing channel 014 through the liquid distribution pipe 017 to cause the first reaction stream group and the second reaction stream group to mix with each other in the mixing channel 014 of the mixing zone 008. In addition, the outlet end of the liquid distribution pipe 017 is provided with a liquid distributor 016. The liquid distributor 016 can convert the second reaction flow group into smaller droplets or bubbles, so that the second reaction flow group can be more evenly distributed in the first reaction flow group in the mixing channel 014. Moreover, the mixing structure in the mixing channel 014 is more acceptable for mixing liquid-phase flow and gas-phase flow. At this time, the first group of reaction stream is a liquid-phase stream, and the second group of reaction stream is a gas-phase stream. The gas-phase flow can be formed into dispersed microbubbles by the liquid distributor 016 to increase the contact area with the liquid-phase flow, and at the same time can also influence the liquid-phase flow to a greater extent, thereby improving the uniformity of mixing of the two flows.

In addition, as shown in FIG. 4, the mixing channel 014 is a cavity extending along the first direction, that is, the mixing channel 014 has a substantially tubular structure, thereby allowing flow therein to flow along the first direction to form a stable piston flow.

The preferred microchannel reactor provided by the present invention, by designing the structure of the mixing channel and the mixing mode therein, can achieve continuous and efficient mixing of the reaction stream, and at the same time can maintain the flow of the reaction liquid in a piston flow mode, ensure that the residence time of the reaction liquid is constant as much as possible, and avoid selectivity for undesirable products due to residence time distribution.

More specifically, the liquid distributor 016 is at least one selected from a micropore powder sintered body, a mesoporous foam, a wire mesh, a microslit tube, or a micropore tube. The micropore powder sintered body can be produced by sintering powder into a micropore structure through a powder metallurgy process; The hollow/mesoporous foam is a hollow microchannel with mesh frames, the wire mesh is a mesh structure with micropores, and the tube is provided with micro-slits or micro-holes, which can all disperse the liquid from the tube 017 to distribute the liquid into smaller bubbles or droplets.

Preferably, the liquid distributor 016 is a cylindrical powder sintered body with micropores, and the mixing channel 014 has a circular cross-section. The liquid distributor 016 may be a structure having substantially the same outer diameter as the liquid distribution pipe 017, the cross-sectional shape of the liquid distributor 016 substantially matches the cross-sectional shape of the mixing channel 014, and the liquid distributor 016 may be positioned coaxially with the mixing channel 014 to allow the liquid flow dispersed by the liquid distributor 016 to mix more evenly with the flow in the mixing channel 014 and form a stable and uniform piston flow to eliminate inconsistency in the residence time of the flow.

In addition, the liquid distributor 016 has a cross-sectional area of 0.01-200 cm ² and a length of 1-2000 mm. Mixing channel 014 has a cross-sectional area of 0.05-400 cm ² and a length of 50-5000 mm. The length and cross-sectional area of the mixing channel 014 are both greater than the length and cross-sectional area of the liquid distributor 016.

In addition, the mixing zone 008 is provided with 2-100 (preferably 2-50, more preferably 2-10) mixing channels 014, the liquid distribution pipe 017 includes a main pipe extending from the outside of the housing 003 to the supply zone 023, and branch pipes, passing from the supply zone 023 into each mixing channel 014 with liquid distributors 016 connected to the ends of the outlet pipes. A plurality of mixing channels 014 are respectively in communication with the supply zone 023, and the first reaction stream group is divided into a plurality of portions in the mixing channels, which play a role in dispersing the first reaction stream group and allowing the first reaction stream group to form a stable, uniform piston flow. The liquid distribution pipe 017 includes a main pipe and branch pipes, wherein the main pipe is connected to the BF ₃ gas inlet and extends from the position of the housing 003 corresponding to the supply zone 023 to the supply zone 023, and the branch pipes extend from the supply zone 023 to the mixing stations. channels 014. That is, the liquid distribution pipe 017 extends from the supply zone 023 to the mixing channels 014. The mixing zone 008 and the supply zone 023 may be separated by a first partition wall 019. The first partition wall 019 is provided with a plurality of through holes, and each mixing channel 014 aligned with each through hole, so that the mixing zone 008 is in communication with the feeding zone 023.

In addition, in the mixing channel 014, the first mixing element 015 is located downstream of the liquid distributor 016. In the mixing channel 014, the downstream position of the liquid distributor 016 refers to a position downstream in the direction of liquid flow (that is, downstream of the liquid distributor 016 in the first direction), that is, at a position closer to the reaction zone 009 than to the liquid distributor 016. Through the first mixing element 015, liquid can be further mixed to improve the uniformity of mixing of the two groups of flows.

More specifically, the first mixing element 015 is provided with a main flow portion and a branch flow portion that are alternately arranged and in communication along the first direction. The main flow section is provided with one main flow passage 0001, and the diverter flow section is provided with a plurality of diverter flow passages 0002. As shown in FIG. 5, one or more main flow portions/diversion stream portions may accordingly be provided and arranged alternately, with only one main flow passage 0001 located in the main flow portion and a plurality of diversion flow passages 0002 located in the diversion stream portion. The liquid converges in the main flow passage 0001 and is distributed in the diverter flow passages 0002 of each part of the diverter flow. By such a convergence-distribution process, the degree of turbulence can be generally increased and the uniformity of liquid mixing can be improved.

Moreover, in the first mixing element 015, a collection cavity 0003, which is in communication with a plurality of exhaust flow passages 0002, is located downstream of the exhaust flow portion 0002. As shown in FIG. 5, the volume (especially the cross-sectional area) of the collection cavity 0003 is larger than the volume (especially the cross-sectional area) of the main flow passage 0001, and the collection cavity 0003 can bring together a plurality of upstream passages 0002 in the diversion flow, and this cavity is in communication with the next passage 0001 of the main stream or with the next stage of the reaction zone 009 or transition zone 020.

In FIG. 5 shows a first mixing element 015 according to an embodiment of the present invention, which is formed by splicing a plurality of plate elements (the number may be 2-100, preferably 2-50, more preferably 10-30, and the thickness is approximately 0.2-10 mm) located along the first direction, and structures such as holes and cavities are formed on each plate member that correspond to the main flow passage 0001, the exhaust flow passage 0002 and the collection cavity 0003, which is convenient for processing and production.

In addition, the mixing zone 008 includes a first heat exchange cavity located in the housing 003, a mixing channel 014 is located in the first heat exchange cavity 013, the housing 003 is provided with a first heat exchange medium inlet 004 and a first heat exchange medium outlet 005, which are in communication with the first heat exchange medium cavity 013. In the mixing zone 008, the mixing channel 014 and the first heat exchange cavity 013 are isolated from each other and are not in communication with each other, but heat transfer between them can be ensured, and pipe fittings with good thermal conductivity can be used in the mixing channel 014. By supplying the heat exchange medium to the first heat exchange medium inlet 004 and discharging the heat exchange medium through the first heat exchange medium outlet 005 in the first heat exchange cavity 013, a circulating flow of the heat exchange medium can be formed to realize heat exchange with the mixing channel 014 and the liquid therein, then is to realize the heat dissipation of the mixing channel 014 and the liquid therein, and to ensure that the heat generated by mixing and dissolving the liquid in the mixing channel 014 is dissipated over time, so that the liquid therein is in a suitable temperature range.

In addition, the volume ratio of the first heat exchange cavity 013 to the mixing channel 014 is 2-50; preferably, the volume ratio of the first heat exchange cavity 013 to the mixing channel 014 is 5-30. The volume of the first heat exchange cavity 013 is larger than the volume of the mixing channel 014, so that the heat generated due to the mixing and dissolution of the first reaction flow group and the second reaction flow group is removed in a timely manner.

In addition, a transition zone 020 is provided between the mixing zone 008 and the reaction zone 009, the transition zone 020 being provided with a stabilizing channel 021 with a constant cross-section and a diffusion channel 022 with a gradually increasing cross-section, which are located and in communication along the first direction; the stabilizing channel 021 is in communication with the mixing channel 014, and the diffusion channel 022 is in communication with the reaction zone 009. The transition zone 020 can bring together mixed liquids from a plurality of mixing channels 014 in the stabilizing channel 021 to achieve another uniform mixing, and then supply the mixed liquid into the reaction zone 009 through the diffusion channel 022. In addition, the transition zone 020 is equipped with a stabilizing channel 021 and a diffusion channel 022, the stabilizing channel 021 mainly realizes the convergence and mixing of liquids, and the diffusion channel 022 is shaped like a bell, which, for example, distributes the mixed liquid into a plurality of reaction channels 010, as described below. The two ends of the transition zone 020 are respectively provided with partition walls with through holes so that they are isolated from the mixing zone 008 (mainly the first heat exchange cavity 013) and the reaction zone 009 (mainly the second heat exchange cavity 012) and are in communication with each mixing channel 014 and each parallel reaction channel 010 through each through hole on each partition wall, and the diffusion channel 022 and the stabilizing channel 021 may be pipe fittings provided between the two partition walls.

In addition, the stabilizing channel 021 can be connected to the outlet pipe 018 extending to the outside of the housing 003. As mentioned above, the stabilizing channel 021 has the function of convergence and mixing, and the outlet pipe 018 can release bubbles and flows accumulated in the stabilizing channel 021. to eliminate the influence of bubble accumulation on mixing uniformity and flow blocking. A valve can be installed on the outlet pipe 018, and the valve can be opened when bubbles or flows need to be released.

In addition, the diffusion channel 022 is provided with a diffusion plate with holes or slits. The diffusion plate may be substantially perpendicular to the first direction. The liquid in the diffusion channel 022 can flow through the cells or slits on the diffusion plate, so that the liquid is dispersed and the uniformity of the mixed liquid is improved.

The reaction zone 009 is provided with a plurality of parallel reaction channels 010 extending along the first direction and in communication with the mixing channel 014 through the stabilizing channel 021 and the diffusion channel 022. The reaction channel 010 provides a reaction space for the mixed liquid and transfers the mixed liquid to flow to the next stage collection area 024 along the first direction, so that the mixed liquid reacts, thereby forming a stable piston flow 010 in the reaction channel to eliminate unwanted products due to the variability of the residence time distribution. As stated above, a transition zone 020 may be provided between the reaction zone 009 and the mixing zone 008, and a plurality of reaction channels 010 may be in communication with the diffusion channel 022, so that the mixed liquid in the diffusion channel 022 is uniformly distributed into the plurality of reaction channels 010. Amount reaction channels is, for example, 2-10000 channels, preferably 2-5000 channels and more preferably 2-500 channels. The reaction channel 010 may have a cross-section of at least one of circular, rectangular and triangular shapes.

In addition, the reaction channel 010 is provided with a second mixing element 011, and the second mixing element 011 includes a support bar 0004 extending along the first direction, and a toothed element 0005 connected to the support bar 0004 and extending transversely to the support bar 0004. In the second mixing element 011, the support bar 011 the bar 0004 provides support for a plurality of gear members 0005, so that the gear members 0005 can be stably held in the reaction channel 010, and the gear members 0005 extend approximately across the reaction channel 010, which can improve the degree of turbulence of the liquid in the reaction channel 010, thereby improving the uniformity of mixing between reaction streams.

In addition, the 0005 gear elements are in one of triangular, arcuate, wavy and spiral shapes. The toothed elements may have different shapes as they extend across the reaction channel 010 and may provide the effect of increasing the degree of turbulence of the liquid.

Preferably, the toothed element 0005 has a triangular shape, and on one side of the triangle adjacent to the support bar 0004, one corner is connected to the support bar 0004, and the other corner is spaced 0.01-20 mm from the support bar 0004. The toothed elements 0005 may be triangular plate elements and are connected to the support strip 0004 using only one corner.

Preferably, each reaction channel 010 is provided with a plurality of second mixing elements 011 (the number may be 2-100, preferably 2-50, more preferably 10-30), which are stacked on top of each other at intervals; and a plurality of second mixing elements 011 are stacked on each other at intervals, and accordingly the gear elements 0005 are also stacked on each other at intervals, and the gear elements 0005 of different second mixing elements 011 are arranged in a staggered manner, so that the different second mixing elements 011 are arranged more unevenly , and the degree of turbulence of the liquid in the reaction channel 010 can be improved to a greater extent.

Preferably, the cross-section of the reaction channel 010 is rectangular, and the toothed elements 0005 extend between a set of opposite sides of the rectangle. More specifically, the reaction channel 010 has four side walls, that is, two sets of opposite parallel side walls, a support bar 0004 is located on one side wall of the reaction channel 010, and toothed elements 0005 extend towards the other opposite side wall, and a plurality of second mixing elements 011 may better conform to the structure of the inner cavity of the reaction channel 010 having a square column shape.

The reaction channel 010 has a cross-sectional area of 1-150 mm ² and a length of 50-5000 mm, the minimum distance between the reaction channels 010 is 1-50 mm, and the second mixing element 011 has a thickness of 0.1-3 mm, and the gap between adjacent gear elements 0005 is 1-50 mm.

Preferably, the reaction channel 010 has a length of 100-3000 mm, the minimum gap between the reaction channels 010 is 3-30 mm, the second mixing element 011 has a thickness of 0.2-2 mm, the gap between adjacent toothed elements 0005 is 1.5-20 mm. The minimum spacing of the reaction channels 010 reflects the density of the reaction channels 010 in the reaction zone 009. Preferably, in the second mixing element 011, the gear element 0005 is a plate element, which may be coplanar with the support bar 0004, and the thickness of the second mixing element 011 is approximately equal to the thickness of the gear element 0005 .

In addition, the reaction zone 009 may be provided with a second heat exchange cavity 012 located in the housing 003; the reaction channel 010 is located in the second heat exchange cavity 012, the housing 003 is provided with a second heat-conducting medium inlet 006 and a second heat-conducting medium outlet 007, which are in communication with the second heat exchange cavity 012. The second heat exchange cavity 012 may be advantageously formed by the housing 003, and on at the two ends are respectively a second dividing wall 025 between the reaction zone 009 and the collection zone 024 and a dividing wall between the reaction zone 009 and the transition zone 020. Through the second heat-conducting medium inlet 006 and the second heat-conducting medium outlet 007, the heat exchange medium can be introduced into the second heat exchange medium a cavity 012 for performing a heat exchange treatment on the reaction channel 010 to ensure that the liquid in the reaction channel 010 reacts within an appropriate temperature range and to prevent the production of undesirable products.

In addition, the first heat exchange cavity 013 and the second heat exchange cavity 012 may be connected to each other in series and located on the same heat exchange circulation flow path, or may also be located in parallel on the same heat exchange flow circulation path, or may be located on two different circulation paths heat transfer flow, respectively.

In addition, the volume ratio of the second heat exchange cavity 012 to the reaction channel 010 is 2-50; preferably, the volume ratio of the second heat exchange cavity 012 to the reaction channel 010 is 5-30. The volume of the second heat exchange cavity 012 is larger than the volume of the reaction channel 010, so that the heat in the reaction channel 010 can be removed in time to ensure a suitable temperature of the reaction channel 010.

In embodiments of the invention, preferred structural components or parameters are used without re-listing when the preferred microchannel reactor is used, unless otherwise noted.

The preferred microchannel reactor of the present invention can be used for the synthesis of polyalpha-olefin synthetic oil; supply pipe 002 can be used to introduce a mixture of olefin raw material and auxiliary raw material, and liquid distribution pipe 017 can be used to introduce BF ₃ gas. A mixture of olefin feedstock and auxiliary feedstock is used as a continuous phase to be supplied to the microchannel reactor feed zone 023 from the feed pipe 002, and BF ₃ gas (having a BF ₃ gas to alpha-olefin mass ratio of 1 to 4%) is used in as a dispersed phase for supply to the mixing channel 014 of the reactor from the pipe 017 for liquid distribution. BF ₃ is supplied in gaseous form and is partially dissolved in the continuous phase by means of a liquid distributor 016. The mixed liquid, which is completely reacted in the reaction channel 010, enters the collection zone 024 and is finally discharged from the outlet pipe 001. Preferably, the mixture of olefin feed material, auxiliary raw material and BF ₃ gas is supplied from the feed pipe 002.

In FIG. 8 is a schematic view of a comparative apparatus of the present invention, which differs from this apparatus in that there is only one high pressure separation unit 3, and there is no low pressure separation unit 4, and the high pressure separation unit 3 is directly connected to the pressure control unit 7.

Example 1

Polymerization of the olefin feedstock is carried out using the setup shown in FIG. 1. In the installation, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a conventional microchannel reactor filled with mixing plates (not the preferred microchannel reactor of the invention), the high pressure separation unit 3 is a high pressure separator, the low pressure separation unit 4 is a low pressure separator, the gas circulation unit 5 is a compressor, the post-treatment unit 6 is a water washing device, and the pressure control unit 7 is a check valve.

In the installation, the mixer has the following structure and parameters: the permissible temperature range of the process fluid is 20-200°C, the upper limit of the operating pressure (25°C) is 10 MPa; the microchannel reactor has the following structure and parameters: 8 parallel channels, process fluid temperature range from -20 to 200°C, maximum permissible reaction pressure 6 MPa, maximum permissible pressure of the heat exchange medium 2 MPa, includes two temperature sensors for measuring the temperature in the reaction system, liquid channel volume (without mixing disk) 50 ml, reaction volume (in case of filling with mixing plates) 30 ml, volumetric flow rate 3-30 l/h, with a main pipe for introducing the reaction gas and outlet pipes for distributing the reaction gas into each channel ; the high-pressure separator has a volume of 1 l and a diameter of 10 cm; the low pressure separator has a volume of 15 l and a diameter of 50 cm; the compressor has the following operating parameters: suction pressure from -0.1 to 0.03 MPa, outlet pressure 10 MPa, volumetric flow rate 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer has an effective volume of 10 liters with a gas distributor in the lower part and silica gel filler placed in the upper layer.

The mixed stream obtained by mixing 1-nonene and n-butanol in a mixer and BF ₃ gas are each independently passed into a microchannel reactor, while BF ₃ enters the microchannel reactor through the main reaction gas pipe, and the volumetric flow rate of BF ₃ is 52 l/h, the volumetric flow rate of 1-nonene is 10 l/h, and the volumetric flow rate of n-butanol is 0.1 l/h. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. The resulting intermediate stream enters the high pressure separator. The intermediate stream undergoes a first gas-liquid separation in a high pressure separator. The separation temperature is 20°C, and the separation pressure is 4 MPa. The separated liquid phase enters the low pressure separator for the second gas phase separation. The separation temperature is 20°C and the separation pressure is -0.01 MPa. The liquid phase separated from the low pressure separator is washed with water using an aqueous washing device to obtain a polyolefin product. The BF ₃ gases separated from the high pressure separator and low pressure separator are recirculated using a compressor. The gas pressure at the compressor outlet is 4 MPa. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. BF ₃ -gas recovery is 40%. The test results are presented in Table 1.

Table 1

Composition distribution of olefin sample Content Monomer, % 3.3 Dimer, % 8.1 Trimer, % 38.9 Tetramer, % 28.3 Pentamer, % 17.2 ≥Hexamer, % 4.2 Conversion, % 96.7

Comparative example 1

The low pressure separator is removed from the installation used in Example 1, the high pressure separator is directly connected in series with the check valve and the compressor, and the high pressure separator is directly connected with the water washing device of the after treatment unit.

Polymerization of the olefin starting material is carried out using the above-mentioned apparatus. In the installation, the mixer has the following structure and parameters: permissible temperature range of the process fluid 20-200°C, upper limit of operating pressure (25°C) 10 MPa; the microchannel reactor has the following structure and parameters: 8 parallel channels, temperature range of the process fluid from -20 to 200°C, maximum permissible reaction pressure 6 MPa, maximum permissible pressure of the heat exchange medium 2 MPa, includes two temperature sensors for measuring the temperature in the reaction system, liquid channel volume (without mixing disk) 50 ml, reaction volume (in case of filling with mixing plates) 30 ml, volumetric flow rate 3-30 l/h, with a main pipe for introducing the reaction gas and outlet pipes for distributing the reaction gas into each channel ; the high-pressure separator has a volume of 1 l and a diameter of 10 cm; the compressor has the following operating parameters: suction pressure from -0.1 to 0.03 MPa, outlet pressure 10 MPa, volumetric flow rate 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer has an effective volume of 10 liters, with a gas distributor in the lower part and silica gel filler placed in the upper layer.

The mixed stream obtained by mixing 1-decene and isopropanol and BF ₃ gas are each independently passed into a microchannel reactor; BF ₃ enters the microchannel reactor through the reaction gas main pipe, the volumetric flow rate of BF ₃ is 78 L/hour, the volumetric flow rate of 1-nonene is 10 L/hour, and the volumetric flow rate of isopropanol is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 25°C, and the pressure is 4 MPa. The resulting intermediate stream enters the high pressure separator. The intermediate stream undergoes gas-liquid separation in a high-pressure separator. The separation temperature is 20°C, and the separation pressure is 4 MPa. The separated liquid phase is washed with water using an aqueous washing device to obtain a polyolefin product. BF ₃ -Gas separated from the high pressure separator is recirculated using a compressor. The gas pressure at the compressor outlet is 4 MPa. The test results show that the efficiency of the high pressure separator is relatively low, and the recovery of BF ₃ gas is only 20%. Once the system is running stable, a small sample of the polyolefin product is taken from the high pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The test results are presented in Table 2.

table 2

Composition distribution of olefin sample Content Monomer, % 2.5 Dimer, % 7.9 Trimer, % 39.1 Tetramer, % 28.5 Pentamer, % 17.5 ≥Hexamer, % 4.5 Conversion, % 97.5

Comparative example 2

Polymerization of the olefin feedstock is carried out using the polyalphaolefin production plant shown in Example 1.

In the installation, the mixer has the following structure and parameters: permissible temperature range of the process fluid 20-200°C, upper limit of operating pressure (25°C) 10 MPa; the microchannel reactor has the following structure and parameters: 8 parallel channels, temperature range of the process fluid from -20 to 200°C, maximum permissible reaction pressure 6 MPa, maximum permissible pressure of the heat exchange medium 2 MPa, includes two temperature sensors for measuring the temperature in the reaction system, liquid channel volume (without mixing disk) 50 ml, reaction volume (in case of filling with mixing plates) 30 ml, volumetric flow rate 3-30 l/h, with a main pipe for introducing the reaction gas and outlet pipes for distributing the reaction gas into each channel ; the high-pressure separator has a volume of 1 l and a diameter of 10 cm; the low pressure separator has a volume of 15 l and a diameter of 50 cm; the compressor has the following operating parameters: suction pressure from -0.1 to 0.03 MPa, outlet pressure 10 MPa, volumetric flow rate 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer has an effective volume of 10 liters, with a gas distributor in the lower part and silica gel filler placed in the upper layer.

The mixed stream obtained by mixing 1-nonene and n-butanol in a mixer and BF ₃ gas are each independently passed into a microchannel reactor; BF ₃ enters the microchannel reactor through the reaction gas main pipe, the flow rate of BF ₃ is 26 L/hour, the flow rate of 1-nonene is 10 L/hour, and the space flow rate of n-butanol is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. The resulting intermediate stream enters the high pressure separator. The intermediate stream undergoes a first gas-liquid separation in a high pressure separator. The separation temperature is 20°C, and the separation pressure is 4 MPa. The separated liquid phase enters the low pressure separator for the second gas-liquid separation, the separation temperature is 20°C, and the separation pressure is -0.01 MPa. The liquid phase separated from the low pressure separator is washed with water using an aqueous washing device to obtain a polyolefin product. BF ₃ -Gases separated from the high pressure separator and low pressure separator are recirculated using a compressor. The gas pressure at the compressor outlet is 4 MPa. BF ₃ -gas recovery is 40%. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The test results are presented in Table 3.

Table 3

Composition distribution of olefin sample Content Monomer, % 36.7 Dimer, % 12.1 Trimer, % 25.2 Tetramer, % 17.8 Pentamer, % 5.1 ≥Hexamer, % 3.1 Conversion, % 63.3

Example 2

Polymerization of the olefin feedstock is carried out using the setup shown in FIG. 2.

In the apparatus used in this example, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a conventional microchannel reactor filled with mixing plates (not the preferred microchannel reactor of the invention), the high pressure separation unit 3 is a high pressure separator unit The low-pressure separation unit 4 is a low-pressure separator, the gas circulation unit 5 is a compressor, the post-processing unit 6 is a water washing device, the pressure control unit 7 is a check valve, and the gas purification unit 8 is a dryer.

In the installation, the mixer has the following structure and parameters: permissible temperature range of the process fluid 20-200°C, upper limit of operating pressure (25°C) 10 MPa; the microchannel reactor has the following structure and parameters: 8 parallel channels, temperature range of the process fluid from -20 to 200°C, maximum permissible reaction pressure 6 MPa, maximum permissible pressure of the heat exchange medium 2 MPa, includes two temperature sensors for measuring the temperature in the reaction system, liquid channel volume (without mixing disk) 50 ml, reaction volume (in case of filling with mixing plates) 30 ml, volumetric flow rate 3-30 l/h, with a main pipe for introducing the reaction gas and outlet pipes for distributing the reaction gas into each channel ; the high-pressure separator has a volume of 1 l and a diameter of 10 cm; the low pressure separator has a volume of 15 l and a diameter of 50 cm; the compressor has the following operating parameters: suction pressure from -0.1 to 0.03 MPa, outlet pressure 10 MPa, volumetric flow rate 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer is an adsorption dryer, has an effective volume of 10L, with a gas distributor at the bottom and silica gel filler placed at the top layer.

The mixed stream obtained by mixing 1-decene and n-butanol and BF ₃ gas are each independently passed into a microchannel reactor; BF ₃ enters the microchannel reactor through the reaction gas main pipe, the flow rate of BF ₃ is 78 L/hour, the flow rate of 1-decene is 10 L/hour, and the space flow rate of n-butanol is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. The resulting intermediate stream enters the high pressure separator. The intermediate stream undergoes a first gas-liquid separation in a high pressure separator. The separation temperature is 20°C, and the separation pressure is 4 MPa. The separated liquid phase enters the low pressure separator for the second gas-liquid separation, the separation temperature is 20°C, and the separation pressure is -0.01 MPa. The liquid phase separated by the low-pressure separator is washed with water using the water-washing device of the post-processing unit 6 to obtain the final polyolefin product. The gas phases (BF ₃ gases) separated from the high pressure separator and the low pressure separator are dried using a dryer and recirculated using a compressor. The gas pressure at the compressor outlet is 4 MPa. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. BF ₃ -gas recovery is 54%. The test results are presented in Table 4.

Table 4

Composition distribution of olefin sample Content Monomer, % 2.2 Dimer, % 6.1 Trimer, % 40.4 Tetramer, % 29.4 Pentamer, % 17.4 ≥Hexamer, % 4.5 Conversion, % 97.8

Example 3

Polymerization of the olefin feedstock is carried out using the setup shown in FIG. 3.

In the apparatus used in this example, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a conventional microchannel reactor filled with mixing plates (not the preferred microchannel reactor of the invention), the high pressure separation unit 3 is a high pressure separator unit The low pressure separating unit 4 is a low pressure separator, the gas circulation unit 5 is a compressor, the post-processing unit 6 is a sedimentation unit, the pressure control unit 7 is a check valve, and the gas purification unit 8 is a dryer; The mixer, microchannel reactor, high pressure separator, low pressure separator, compressor and dryer are identical to those of Example 1.

The precipitation device effectively separates the incoming stream into a light liquid phase and a heavy liquid phase, and the heavy liquid phase (containing the auxiliary feedstock complex and BF ₃ and unreacted olefin feedstock) is returned to the mixing unit 1 to continue to participate in the continuous reaction. The device is a horizontal gravity sedimentation device, where inside the reservoir of said device there is a cube-shaped container with dimensions of 3000×300×1500 mm and where inside the said container there are inclined coalescence plates and flat plates, and ten flat plates are connected every ten inclined coalescence plates. The gap between the slanted coalescence plates is 30mm, the slant angle is 30°, and the length of the slanted plate is 34mm. The flat plate has a length of 30 mm and a gap of 30 mm.

The mixed stream obtained by mixing 1-decene and n-butanol and BF ₃ gas are each independently passed into a microchannel reactor; BF ₃ enters the microchannel reactor through the reaction gas main pipe, the volumetric flow rate of BF ₃ is 78 L/hour, the volumetric flow rate of 1-decene is 10 L/hour, and the volumetric flow rate of n-butanol is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. The resulting intermediate stream enters the high pressure separator. The intermediate stream undergoes a first gas-liquid separation in a high pressure separator. The separation temperature is 20°C, and the separation pressure is 4 MPa. The separated liquid phase enters the low pressure separator for the second gas-liquid separation, the separation temperature is 20°C, and the separation pressure is -0.01 MPa. The liquid phase separated by the low-pressure separator enters the sedimentation device of the post-treatment unit 6, where separation by precipitation occurs, and is separated into a light liquid phase and a heavy liquid phase. The light liquid phase is the crude polyolefin product, which is washed with water to obtain the finished polyolefin product; the heavy liquid phase contains a complex of auxiliary raw materials and BF ₃ and unreacted olefin starting material and is returned to the mixing unit 1. The gas phases separated from the high pressure separator and low pressure separator are dried using a dryer, compressed by a compressor and recycled for reuse. The gas pressure at the compressor outlet is 4 MPa. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The recovery of the complex catalyst is 65%, and the recovery of BF ₃ gas is 75.45%. The test results are presented in Table 5.

Table 5

Composition distribution of olefin sample Content Monomer, % 2.9 Dimer, % 7.5 Trimer, % 39.1 Tetramer, % 28.6 Pentamer, % 17.6 ≥Hexamer, % 4.3 Conversion, % 97.1

Example 4

Polymerization of the olefin feedstock is carried out using the polyolefin production plant shown in FIG. 3.

In the apparatus used in this example, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a conventional microchannel reactor filled with mixing plates (not the preferred microchannel reactor of the invention), the high pressure separation unit 3 is a high pressure separator unit Low pressure separation 4 is a low pressure separator, gas circulation unit 5 is a compressor, post-processing unit 6 is a centrifugation device, pressure control unit 7 is a check valve, gas purification unit 8 is a dryer; the dryer has an effective volume of 10 liters, with a gas distributor in the lower part and silica gel filler placed in the upper layer; The mixer, microchannel reactor, high pressure separator, low pressure separator and compressor are identical to those of Example 1.

The centrifugation device actually ensures that the incoming stream is separated into a light liquid phase and a heavy liquid phase, and the heavy liquid phase (containing the auxiliary raw material complex and BF ₃ and unreacted olefin feed material) is returned to the mixing unit 1 to continue to participate in the continuous reaction.

The centrifugation device is a high-speed tubular separator, the rotation speed of the rotary drum is 10-30000 rpm, the separation degree is no less than 15000G; the temperature during separation by centrifugation is 10-60°C, and the residence time during centrifugation is 10-1000 sec.

The mixed stream obtained by mixing 1-decene and n-butanol in a mixer and BF ₃ gas are each independently passed into a microchannel reactor; BF ₃ enters the microchannel reactor through the reaction gas main pipe, the flow rate of BF ₃ is 78 L/hour, the flow rate of 1-decene is 10 L/hour, and the space flow rate of n-butanol is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. The resulting intermediate stream enters the high pressure separator. The intermediate stream undergoes a first gas-liquid separation in a high pressure separator. The separation temperature is 20°C, and the separation pressure is 4 MPa. The separated liquid phase enters the low pressure separator for the second gas-liquid separation, the separation temperature is 20°C, and the separation pressure is -0.01 MPa. The liquid phase separated by the low pressure separator enters the centrifugation device of the post-processing unit 6. In the centrifugation device, the separated light liquid phase is a crude polyolefin product, which is washed with water to obtain a finished polyolefin product; the separated heavy liquid phase contains a complex of auxiliary raw materials and BF ₃ and unreacted olefin starting material, and is returned to the mixing unit 1 to continue to participate in the continuous reaction. The gas phases (BF ₃ gas) separated from the high pressure separator and low pressure separator are dried using a dryer, compressed by a compressor and recycled for reuse. The gas pressure at the compressor outlet is 4 MPa. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The recovery of the complex catalyst is 80%. The total recovery of BF ₃ gas is 80.4%. The test results are presented in Table 6.

Table 6

Composition distribution of olefin sample Content Monomer, % 2.1 Dimer, % 7.3 Trimer, % 39.4 Tetramer, % 29.0 Pentamer, % 17.6 ≥Hexamer, % 4.6 Conversion, % 97.9

Comparative example 3

Polymerization of the olefin feedstock is carried out using only mixers, a microchannel reactor and a centrifugation device that are identical to those used in the polyalphaolefin production plant in Example 4.

The mixed stream obtained by mixing 1-decene and n-butanol, BF ₃ gas, in a mixer is passed into a microchannel reactor; BF ₃ enters the microchannel reactor through the reaction gas main pipe, the volumetric flow rate of BF ₃ is 78 L/hour, the volumetric flow rate of 1-decene is 10 L/hour, and the volumetric flow rate of n-butanol is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. The intermediate product from the microchannel reactor enters directly into the centrifugation device; BF ₃ gas is not extracted. In the centrifugation device, the separated light liquid phase is a crude polyolefin product, which is washed with water to obtain a finished polyolefin product; the separated heavy liquid phase contains a complex of auxiliary raw materials and BF ₃ and unreacted olefin starting material, and is returned to the mixing unit 1 to continue to participate in the continuous reaction. The recovery of the complex catalyst is 80%. The total recovery of BF ₃ gas is 26.4%. A small amount of the polyolefin product is sampled and measured using gas chromatography to determine the content of each component in the product. The test results are presented in Table 7.

Table 7

Composition distribution of olefin sample Content Monomer, % 3.4 Dimer, % 8.0 Trimer, % 39.1 Tetramer, % 28.2 Pentamer, % 17.0 ≥Hexamer, % 4.3 Conversion, % 96.8

Example 5

Polymerization of the olefin feedstock is carried out using the polyolefin production plant shown in FIG. 2.

In the plant, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a preferred microchannel reactor (the preferred microchannel reactor of the present invention), shown in FIG. 4, high pressure separation unit 3 is a high pressure separator, low pressure separation unit 4 is a low pressure separator, gas circulation unit 5 is a compressor, post treatment unit 6 is a water washing device, pressure control unit 7 is a check valve , and the gas purification unit 8 is a dryer; The mixer, high pressure separator, low pressure separator and compressor are identical to these devices of example 1.

In the installation, the microchannel reactor contains 5 parallel reaction channels 010, each reaction channel 010 has a rectangular cross-section with a cross-sectional area of 20 mm ² , the reaction channel 010 has a length of 2000 mm. The second mixing element 011 in the reaction channel 010 has triangular gear elements 0005, the gap between adjacent gear elements 0005 is 5 mm. In the reaction channel 010, a total of four layers of superimposed mixing elements 011 are arranged, as shown in FIG. 7. In the installation, the high pressure separator has a volume of 1 liter and a diameter of 10 cm; the low pressure separator has a volume of 15 l and a diameter of 50 cm; the compressor has a suction pressure of -0.1 to 0.03 MPa, an outlet pressure of 10 MPa, and a volumetric flow rate of 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer has an effective volume of 10 liters, with a gas distributor in the lower part and silica gel filler placed in the upper layer.

A mixed stream obtained by mixing 1-decene and n-butanol in a mixer is passed into the microchannel reactor through a feed pipe 002 and BF ₃ gas through a liquid distribution pipe 017; the BF ₃ flow rate is 78 L/hour, the decene flow rate is 10 L/hour, and the n-butanol flow rate is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. BF ₃ -Gas separated from the high pressure separator and low pressure separator is dried using a dryer, compressed by a compressor and recycled for reuse. The gas pressure at the compressor outlet is 4 MPa. BF ₃ -gas recovery is 54%. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The test results are presented in Table 8.

Table 8

Composition distribution of olefin sample Content Monomer, % 0.3 Dimer, % 2.7 Trimer, % 43.0 Tetramer, % 31.5 Pentamer, % 18.1 ≥Hexamer, % 4.4 Conversion, % 99.7

Comparative example 4

Polymerization of the olefin feedstock is carried out using the polyolefin production plant shown in FIG. 2.

In the plant, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a preferred microchannel reactor (the preferred microchannel reactor of the present invention), shown in FIG. 4, but the reactor is not provided with a mixing channel 014 and a liquid distributor 016, the high-pressure separation unit 3 is a high-pressure separator, the low-pressure separation unit 4 is a low-pressure separator, the gas circulation unit 5 is a compressor, the post-processing unit 6 is water washing device, pressure control unit 7 is a check valve, gas cleaning unit 8 is a dryer; The mixer, high pressure separator, low pressure separator and compressor are identical to these devices of example 1.

In the installation, the microchannel reactor contains 5 parallel reaction channels 010, each reaction channel 010 has a rectangular cross-section with a cross-sectional area of 20 mm ² , the reaction channel 010 has a length of 2000 mm. The second mixing element 011 in the reaction channel 010 has triangular gear elements 0005, the gap between adjacent gear elements 0005 is 5 mm. In the reaction channel 010, a total of four layers of superimposed mixing elements 011 are arranged, as shown in FIG. 7.

In the installation, the high-pressure separator has a volume of 1 l and a diameter of 10 cm; the low pressure separator has a volume of 15 l and a diameter of 50 cm; the compressor has a suction pressure of -0.1 to 0.03 MPa, an outlet pressure of 10 MPa, and a volumetric flow rate of 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer has an effective volume of 10 liters, with a gas distributor in the lower part and silica gel filler placed in the upper layer.

A mixed stream obtained by mixing 1-decene and n-butanol in a mixer is passed into the microchannel reactor through a feed pipe 002 and BF ₃ gas through a liquid distribution pipe 017; the BF ₃ flow rate is 78 L/h, the decene flow rate is 10 L/h, and the n-butanol flow rate is 0.1 L/h. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. BF ₃ -Gas separated from the high pressure separator and low pressure separator is dried using a dryer, compressed by a compressor and recycled for reuse. The gas pressure at the compressor outlet is 4 MPa. BF ₃ -gas recovery is 58%. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The test results are presented in Table 9.

Table 9

Composition distribution of olefin sample Content Monomer, % 19.4 Dimer, % 13.2 Trimer, % 23.9 Tetramer, % 23.4 Pentamer, % 14.5 ≥Hexamer, % 5.6 Conversion, % 80.6

Example 6

Polymerization of the olefin feedstock is carried out using the polyolefin production plant shown in FIG. 2.

In the plant, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a preferred microchannel reactor (the preferred microchannel reactor of the present invention), shown in FIG. 4, high pressure separation unit 3 is a high pressure separator, low pressure separation unit 4 is a low pressure separator, gas circulation unit 5 is a compressor, post treatment unit 6 is a water washing device, pressure control unit 7 is a check valve , gas purification unit 8 is a dryer; The mixer, high pressure separator, low pressure separator and compressor are identical to these devices of example 1.

In the installation, the microchannel reactor contains 5 parallel reaction channels 010, each reaction channel 010 has a rectangular cross-section with a cross-sectional area of 20 mm ² , the reaction channel 010 has a length of 2000 mm. The second mixing element 011 in the reaction channel 010 has triangular gear elements 0005, the gap between adjacent gear elements 0005 is 5 mm. In the reaction channel 010, a total of four layers of superimposed mixing elements 011 are arranged, as shown in FIG. 7. The reactor contains one mixing channel 014, which has a cross-sectional area of 10 cm ² and a length of 800 mm. The liquid distributor 016 is a micropore metal powder sintered body having an average pore size of 5 μm, a cross-sectional area of 8.5 cm ² and a length of 150 mm. Three first mixing elements 015 are provided in the mixing channel 014.

In the installation, the high-pressure separator has a volume of 1 l and a diameter of 10 cm; the low pressure separator has a volume of 15 l and a diameter of 50 cm; the compressor has a suction pressure of -0.1 to 0.03 MPa, an outlet pressure of 10 MPa, and a volumetric flow rate of 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer has an effective volume of 10 liters, with a gas distributor in the lower part and silica gel filler placed in the upper layer.

A mixed stream obtained by mixing 1-decene and n-butanol in a mixer is passed into the microchannel reactor through a feed pipe 002 and BF ₃ gas through a liquid distribution pipe 017; the BF ₃ flow rate is 78 L/h, the decene flow rate is 10 L/h, and the n-butanol flow rate is 0.1 L/h. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. BF ₃ -Gas separated from the high pressure separator and low pressure separator is dried using a dryer, compressed by a compressor and recycled for reuse. The gas pressure at the compressor outlet is 4 MPa. BF3 gas recovery is 55%. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The test results are presented in Table 10.

Table 10

Composition distribution of olefin sample Content Monomer, % 4.9 Dimer, % 10.5 Trimer, % 38.2 Tetramer, % 27.5 Pentamer, % 15.7 ≥Hexamer, % 3.2 Conversion, % 95.1

Example 7

Polymerization of the olefin feedstock is carried out using the polyolefin production plant shown in FIG. 2.

In the apparatus, the mixing unit 1 is a mixer, the microchannel reaction unit 2 is a preferred microchannel reactor (the preferred microchannel reactor of the present invention), shown in FIG. 4, high pressure separation unit 3 is a high pressure separator, low pressure separation unit 4 is a low pressure separator, gas circulation unit 5 is a compressor, post treatment unit 6 is a water washing device, pressure control unit 7 is a check valve , gas purification unit 8 is a dryer; The mixer, high pressure separator, low pressure separator and compressor are identical to these devices of example 1.

In the installation, the microchannel reactor contains 5 parallel reaction channels 010, each reaction channel 010 has a rectangular cross-section with a cross-sectional area of 20 mm ² , the reaction channel 010 has a length of 2000 mm. The second mixing element 011 in the reaction channel 010 has triangular gear elements 0005, the gap between adjacent gear elements 0005 is 5 mm. In the reaction channel 010, a total of four layers of superimposed mixing elements 011 are arranged, as shown in FIG. 7. The reactor contains two mixing channels 014, each of which has a cross-sectional area of 10 cm ² and a length of 800 mm. Each mixing channel 014 is provided with three first mixing elements 015. The liquid distributor 016 016 is made of micro/mesoporous tubular material, and the hollow microchannels constituting the mesh frame of the micro/mesoporous tubular material have a cross-sectional area of 8.5 cm ² , average pore diameter 2 µm and length 150 mm.

In the installation, the high-pressure separator has a volume of 1 l and a diameter of 10 cm; the low pressure separator has a volume of 15 l and a diameter of 50 cm; the compressor has a suction pressure of 0.1 to 0.03 MPa, an outlet pressure of 10 MPa, and a volumetric flow rate of 3 m ³ /hour; the check valve has a pressure of 6 MPa; The dryer has an effective volume of 10 liters, with a gas distributor in the lower part and silica gel filler placed in the upper layer.

A mixed stream obtained by mixing 1-decene and n-butanol in a mixer is passed into the microchannel reactor through a feed pipe 002 and BF ₃ gas through a liquid distribution pipe 017; the BF ₃ flow rate is 78 L/hour, the decene flow rate is 10 L/hour, and the n-butanol flow rate is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. BF ₃ -Gas separated from the high pressure separator and low pressure separator is dried using a dryer, compressed by a compressor and recycled for reuse. The gas pressure at the compressor outlet is 4 MPa. BF3 gas recovery is 54%. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. The test results are presented in Table 11.

Table 11

Olefin Sample Composition Distribution Content Monomer, % 0.4 Dimer, % 2.8 Trimer, % 43.0 Tetramer, % 31.4 Pentamer, % 15.6 ≥Hexamer, % 6.8 Conversion, % 99.6

Comparative Example 5

The same setup was used as in Example 2, except that no mixing plate was loaded into the microchannel reactor.

The mixed stream obtained by mixing 1-decene and n-butanol and BF ₃ gas are each independently passed into a microchannel reactor; BF ₃ enters the microchannel reactor through the reaction gas main pipe, the flow rate of BF ₃ is 78 L/hour, the flow rate of 1-decene is 10 L/hour, and the space flow rate of n-butanol is 0.1 L/hour. The polymerization reaction is carried out in a microchannel reactor, the reaction temperature is 20°C, and the pressure is 4 MPa. The resulting intermediate stream enters the high pressure separator. The intermediate stream undergoes a first gas-liquid separation in a high pressure separator. The separation temperature is 20°C, and the separation pressure is 4 MPa. The separated liquid phase enters the low pressure separator for the second gas-liquid separation, the separation temperature is 20°C, and the separation pressure is -0.01 MPa. The liquid phase separated by the low-pressure separator is washed with water using the water-washing device of the post-processing unit 6 to obtain the final polyolefin product. The gas phases (BF ₃ gases) separated from the high pressure separator and the low pressure separator are dried using a dryer and recirculated using a compressor. The gas pressure at the compressor outlet is 4 MPa. Once the system is running smoothly, a small sample of the polyolefin product is taken from the low pressure separator, washed with water, and measured using gas chromatography to determine the content of each component in the product. BF3 gas recovery is 53%. The test results are presented in Table 12.

Table 12

Olefin Sample Composition Distribution Content Monomer, % 21.9 Dimer, % 6.1 Trimer, % 25.3 Tetramer, % 22.5 Pentamer, % 14.9 ≥Hexamer, % 9.3 Conversion, % 78.1

The polyolefin products of Examples 1-7 and Comparative Examples 1-5 were distilled and fractionated to produce polyalpha-olefin synthetic oils above 280°C and the 100°C kinematic viscosity and viscosity index were determined. The results are presented in Table 13.

Table 13

Efficiency mark Kinematic viscosity at 100°C, mm ² /sec Viscosity index Example 1 5.245 145 Comparative example 1 5.212 140 Comparative example 2 3.673 126 Example 2 5,247 145 Example 3 5,244 145 Example 4 5,249 146 Comparative example 3 5.139 139 Example 5 5,711 147 Comparative example 4 4.295 131 Example 6 4,769 136 Example 7 5.603 145 Comparative Example 5 4,612 134

As can be seen from the above examples, the polyalphaolefin production plant of the present invention can recover BF ₃ and BF ₃ complexes with a high degree of recovery, thereby eliminating environmental pollution and also reducing reaction costs.

Moreover, as can be seen from the above table, by using the preferred microchannel reactor of the present invention, polyolefin synthetic oil can be produced with high conversion. This is because the reaction channel 010 and the mixing channel 014 are both tubular structures arranged in the same direction, so that the mixed liquid can form a stable piston flow along the first direction, improving the consistency of the residence time of the mixed liquid and eliminating or reducing the formation of undesirable products . In addition, the reaction channel 010 is provided with a second mixing element 011, and the mixing channel 014 is provided with a liquid distributor 016 and a first mixing element 015, which can further improve the degree of turbulence of the mixed liquid, improve mixing uniformity, and eliminate or reduce the production of undesirable products and improve conversion into the target product. Moreover, the final polyalphaolefin synthetic oils have low kinematic viscosity and a high viscosity index.

Preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the technical concept of the invention, various simple modifications can be made to the technical solutions of the invention in any suitable manner, including combinations of various specific technical characteristics. To avoid unnecessary repetition, the different possible combinations are not described in detail here. However, these simple modifications and combinations should also be considered as the disclosed content of the invention, and all of them fall within the scope of protection of the present invention.

Claims (58)

1. Installation for the production of polyalphaolefins, which includes a mixing unit (1), a microchannel reaction unit (2), a high pressure separation unit (3), a low pressure separation unit (4), a gas circulation unit (5), a subsequent unit (6). processing and pressure control unit (7), wherein the mixing unit (1), microchannel reaction unit (2), high pressure separation unit (3), low pressure separation unit (4) and gas circulation unit (5) are connected in series, microchannel the reaction unit (2) is provided with a BF ₃ -gas inlet (01), the mixing unit (1) is provided with an auxiliary raw material inlet (02) and an olefin feed inlet (03), the gas circulation unit (5) is connected to the BF inlet ₃ -gas (01), low pressure separation unit (4) is connected to post-processing unit (6), high pressure separation unit (3), pressure control unit (7) and gas circulation unit (5) are connected in series and optionally unit ( 6) post-processing is connected to the mixing unit (1), where the microchannel reaction unit (2) is one microchannel reactor or a combination of two or more microchannel reactors, and the microchannel reactor has the following structure and parameters: the reaction channel is 2-10000 parallel channels, preferably 2-5000 channels, more preferably 2-500 channels, the operating temperature range is from -70 to 300°C, the permissible maximum reaction pressure does not exceed 20 MPa, the permissible maximum pressure of the heat exchange medium does not exceed 10 MPa; the volume of the liquid channel without mixing inserts is 0.1-20000 l, the volumetric flow rate is 1-50000 l/h; preferably a mixing element which facilitates mixing of the reaction streams is provided in each reaction channel, preferably the microchannel reactor is provided with a main pipe for introducing the reaction gas and outlet pipes for distributing the reaction gas into each reaction channel, and microchannel reactor includes: body (003); a supply zone (023), a mixing zone (008), a reaction zone (009) and a collection zone (024) arranged in series and in communication along a first direction in the housing (003), wherein the housing (003) is provided with a supply pipe (002) , located in communication with the supply zone (023), and the outlet pipe (001), located in communication with the collection zone (024), and the mixing zone (008) is equipped with a mixing channel (014) running along the first direction; pipe (017) for liquid distribution; a liquid distribution pipe (017) extends from the outside of the housing (003) into the mixing channel (014), the liquid distribution pipe (017) is connected to a liquid distributor (016) at the end of the mixing channel (014); the supply pipe (002) is connected to the mixing unit (1) and is configured to introduce a mixture of olefin feedstock and auxiliary raw materials, the liquid distribution pipe (017) is connected to the BF ₃ gas inlet (01) and is configured to introduce BF ₃ -gas; And the outlet pipe (001) is connected to the high pressure separation unit (3). 2. Installation according to claim 1, which differs in that the mixing unit (1) is configured to uniformly mix the flow entering it, the mixing unit (1) is preferably a mixer, more preferably a static mixer and/or a dynamic mixer; and/or microchannel reaction unit (2) is configured to carry out a microchannel reaction of BF ₃ gas from the inlet (01) of BF ₃ gas and a mixed flow of auxiliary raw materials and olefin feed material from the mixing unit (1), microchannel reaction unit (2) preferably a microchannel reactor; and/or the high-pressure separation unit (3) is configured to carry out gas-liquid separation of the intermediate flow entering it, while the separated gas phase enters the gas circulation unit (5) through the pressure control unit (7), and the separated liquid phase enters the unit (4) low pressure separator, the high pressure separator unit (3) is preferably a high pressure separator; and/or the low-pressure separation unit (4) is configured to carry out gas-liquid separation of the intermediate flow entering it, while the separated gas phase enters the gas circulation unit (5), and the separated liquid phase enters the subsequent processing unit (6) (unit (4) the low pressure separator is preferably a low pressure separator); and/or The gas circulation unit (5) ensures the extraction of the BF ₃ gas entering it and the delivery of the extracted BF ₃ gas through the BF ₃ gas inlet (01) to the microchannel reaction unit (2) for reuse, the gas circulation unit (5) can be one or more of a compressor, a gas circulation pump and a vacuum pump; and/or the post-processing unit (6) is configured to post-process the incoming stream to produce a polyolefin product, the post-processing unit (6) is preferably one or more of an adsorption device, an extraction device, a distillation device, a centrifugation device, a sedimentation device , alkaline washing devices and water washing devices; optionally, the post-processing unit is configured to return the heavy liquid phase obtained from it to the mixing unit (1); and/or The pressure regulating unit (7) is configured to regulate the pressure of the microchannel reaction unit (2) and the high pressure separation unit (3), the pressure regulating unit (7) is preferably one or more of a check valve, a throttle valve and a pressure reducing valve . 3. Installation according to claim 1, which is characterized in that the post-processing unit (6) is a sedimentation device or a centrifugation device; a sedimentation device or a centrifugation device ensures that the incoming flow is divided into a light liquid phase and a heavy liquid phase; optionally, the heavy liquid phase is returned to the mixing unit (1) to continue the continuous reaction. 4. Installation according to claim 1, which is characterized in that the pressure control unit (7) is configured to regulate the operating pressure of the microchannel reaction unit (2) so that it is the same as the operating pressure of the high pressure separation unit (3). 5. Installation according to claim 1, which differs in that the gas purification unit (8) is provided between the low pressure separation unit (4) and the gas circulation unit (5) and/or the gas purification unit (8) is provided between the unit (7) pressure regulation and gas circulation unit (5), while the gas purification unit (8) provides drying and/or purification of the BF ₃ gas entering it, the gas purification unit (8) is preferably one or more of a gas filter, an adsorption dryer, freeze dryer and cyclone separator. 6. Installation according to claim 1, which differs in that the liquid distributor is at least one selected from a micropore powder sintered body, a mesoporous foam, a wire mesh, and a microslit or micropore tube; preferably the liquid distributor is a cylindrical powder sintered body with micropores, preferably the liquid distributor has a cross-sectional area of 0.01-200 cm ² and a length of 1-2000 m; and/or the mixing zone is provided with 1-100, preferably 1-50, more preferably 2-10 mixing channels, the liquid distribution pipe includes a main pipe extending from the outside of the housing to the supply zone, and branch pipes extending from the supply zone to each mixing channel, with liquid distributors connected to the ends of the outlet pipes, preferably the mixing channel has a circular cross-section; preferably the mixing channel has a cross-sectional area of 0.05-400 cm ² and a length of 50-5000 mm; and/or in the mixing channel, the first mixing element is located downstream of the liquid distributor; and/or the first mixing element is provided with a main flow portion and a waste flow portion that are alternately arranged and in communication along the first direction, and the main flow portion is provided with one main flow passage, and the waste flow portion is provided with a plurality of exhaust flow passages; and/or a collection cavity in communication with a plurality of diversion flow passages is located downstream of the diversion flow portion; and/or the mixing zone contains a first heat exchange cavity located in the housing; the mixing channel is located in the first heat exchange cavity, the housing is provided with a first heat exchange medium inlet and a first heat exchange medium outlet, which are in communication with the first heat exchange cavity; and/or the volume ratio of the first heat exchange cavity to the mixing channel is 2-50, preferably the volume ratio of the first heat exchange cavity to the mixing channel is 5-30; and/or a transition zone is provided between the mixing zone and the reaction zone; the transition zone is provided with a stabilizing channel with a constant cross-section and a diffusion channel with a gradually increasing cross-section, which are located and in communication along the first direction, and the stabilizing channel is in communication with the mixing channel, and the diffusion channel is in communication with the reaction zone; and/or an exhaust pipe extending to the outside of the housing is connected to a stabilizing channel; and/or the diffusion channel is equipped with a diffusion plate with cells or slits; and/or the reaction zone is provided with a plurality of parallel reaction channels, for example 2-10000 channels, preferably 2-5000 channels, more preferably 2-500 channels extending along the first direction and in communication with the mixing channel through the transition zone; and/or the reaction channel is provided with a second mixing element, and the second mixing element includes a support bar extending along the first direction, and a toothed element connected to the support bar and extending across the support bar; and/or the gear element has at least one of triangular, arcuate, wavy and spiral shapes, preferably the gear element has a triangular shape, and on one side of the triangle adjacent to the support bar, one corner is connected to the support bar and the other corner is spaced 0.01 -20 mm from the support bar; and/or each of the reaction channels is independently provided with a plurality of second mixing elements that are stacked on top of each other at intervals, and the gear elements of the second mixing element are staggered with respect to each other; and/or the reaction channel has a cross-section in the shape of at least one of circular, rectangular and triangular shapes, preferably the cross-section of the reaction channel is rectangular, and the toothed elements extend between a set of opposite sides of the rectangle; and/or the reaction channel has a cross-sectional area of 1-150 mm ² and a length of 50-5000 mm, preferably 100-3000 mm, the minimum distance between the reaction channels is 1-50 mm, preferably 3-30 mm, and the second mixing element has a thickness of 0.1 -3 mm, preferably 0.2-2 mm, and the gap between adjacent toothed elements is 1-50 mm, preferably 1.5-20 mm; and/or the reaction zone is equipped with a second heat exchange cavity located in the housing; wherein the reaction channel is located in the second heat exchange cavity, the housing is equipped with a second inlet of the heat exchange medium and a second outlet of the heat exchange medium, which are in communication with the second heat exchange cavity; and/or the volume ratio of the second heat exchange cavity to the reaction channel is 2-50, preferably the volume ratio of the second heat exchange cavity to the reaction channel is 5-30. 7. Installation according to claim 1, which is characterized in that the mixing unit (1) is additionally equipped with a BF ₃ gas inlet, wherein a mixture of auxiliary raw materials, olefin feed material and BF ₃ gas is supplied to the microchannel reaction unit; preferably the mixing unit (1) comprises a mixer for mixing any two of the auxiliary raw materials, olefin feedstock and BF ₃ gas, and a mixer for further mixing the mixture with a third component; more preferably, the mixing unit (1) comprises a mixer for mixing one of the olefin feedstock and BF ₃ gas with the auxiliary feedstock and a mixer for further mixing the mixture with another component of the olefin feedstock and BF ₃ gas. 8. Installation according to claim 1, which is characterized in that the gas circulation unit (5) is additionally connected to the BF ₃ gas inlet provided in the mixing unit (1). 9. A method for producing polyalphaolefins, which includes: a mixed stream obtained after mixing the olefin starting material and auxiliary raw materials in a mixing unit, and BF ₃ gas are each independently passed into a microchannel reaction unit; the intermediate stream formed after the polymerization reaction in the microchannel reaction unit is passed into the high-pressure separation unit; the intermediate stream undergoes a first gas-liquid separation in a high pressure separation unit; the separated liquid phase enters the low pressure separation unit, and the second gas-liquid separation occurs in the low pressure separation unit; the liquid phase separated from the low pressure separation unit enters the post-processing unit, and the polyolefin product is obtained after processing in the post-processing unit; gas phases BF ₃ -gas separated from the high pressure separation unit and the low pressure separation unit enter the gas circulation unit, BF ₃ -gas is recovered for reuse; optionally, the heavy liquid phase containing the auxiliary feedstock complex and BF ₃ and unreacted olefin feedstock obtained after processing in the post-processing unit is recycled to the mixing unit. 10. The method of claim 9, wherein the olefin in the olefin feedstock is one or more C ₃ -C ₂₀ alpha olefins; optionally, the olefin feedstock further comprises a mixture of C ₅ -C ₂₀ alkanes and/or a C ₁ -C ₂₀ oxygen-containing compound (preferably the olefin feedstock is a Fischer-Tropsch olefin feedstock); and/or the auxiliary raw material is one or more of an alcohol having a carbon number of 1-20, an ether having a carbon number of 1-20, an aldehyde having a carbon number of 1-20, a ketone having a carbon number of 1-20 , an ester having a carbon number of 1-30, a carboxylic acid having a carbon number of 1-20, and a phenol having a carbon number of 1-20. 11. The method according to claim 9, which is characterized in that the rate of entry of the olefin feed material into the mixing unit is 10-5000 l/h, preferably 20-4000 l/h, more preferably 40-2500 l/h; the rate of entry of auxiliary raw materials into the mixing unit is 0.01-1000 l/h, preferably 0.1-800 l/h, more preferably 0.2-500 l/h; The gas delivery rate for BF ₃ gas entering the microchannel reaction unit, including initially introduced BF ₃ gas and optionally recycled BF ₃ gas, is 5-200,000 l/h, preferably 50-100,000 l/h, more preferably 100- 50000 l/h. 12. The method according to claim 9, which is characterized in that the reaction temperature in the microchannel reaction unit is 0-120°C, preferably 10-80°C, more preferably 20-60°C; the reaction pressure in the microchannel reaction unit is 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa; the residence time of the olefin feedstock in the microchannel reaction unit is 1-3600 s, preferably 10-1800 s, more preferably 15-1000 s; in the microchannel reaction unit, the mass ratio of auxiliary raw material:olefin feedstock:total amount of BF ₃ gas is 1:1-1000:1-500, preferably 1:1-500:1-200, most preferably 1:10-250:1 ,5-100. 13. The method according to claim 9, which differs in that the high pressure separation unit is a high pressure separator; the high pressure separator pressure is 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa; the temperature of the high pressure separator is 0-120°C, preferably 10-80°C, more preferably 20-60°C; the volume of the high pressure separator is 0.1-20000 l, preferably 0.2-2000 l; and/or the low pressure separation unit is a low pressure separator; the low pressure separator pressure is -0.1 to 1 MPa, preferably -0.1 to 0.9 MPa, more preferably -0.1 to 0.1 MPa; the temperature of the low pressure separator is 0-120°C, preferably 10-80°C, more preferably 20-60°C; the volume of the low pressure separator is 0.1-20000 l, preferably 0.2-2000 l; and/or the pressure of the recirculated BF ₃ gas through the gas circulation unit is 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa; and/or the pressure of the pressure control unit is 0.01-10 MPa, preferably 0.01-8 MPa, more preferably 0.1-6 MPa. 14. The method according to claim 9, wherein the post-processing method used in the post-processing unit is one or more of adsorption, extraction, distillation, centrifugation, precipitation, alkaline washing and aqueous washing methods, preferably the post-processing method represents sedimentation or centrifugation; Sedimentation or centrifugation separates the stream entering the post-processing unit into a light liquid phase and a heavy liquid phase, the heavy liquid phase optionally being returned to the mixing unit to continue to participate in the continuous reaction. 15. The method according to claim 9, which is characterized in that a gas purification unit is provided between the low pressure separation unit and the gas circulation unit and/or a gas purification unit is provided between the pressure control unit and the gas circulation unit; the gas purification unit provides drying and/or purification of the BF ₃ gas entering it, the gas purification unit is preferably one or more of a gas filter, an adsorption dryer, a freeze dryer and a cyclone separator. 16. The method according to claim 9, which differs in that in the mixing unit, in addition to the olefin source material and auxiliary raw materials, BF ₃ gas is also mixed and the speed of the BF ₃ gas entering the mixing unit is 4-180000 l/h , preferably 45-90000 l/h, more preferably 90-45000 l/h. 17. The method according to claim 16, which is characterized in that the gas phases separated from the high pressure separation unit and the low pressure separation unit, BF ₃ gas, are introduced into the mixing unit. 18. The method according to claim 16, which differs in that, in terms of the total mass of BF ₃ in the microchannel reaction unit, the mass ratio of the BF ₃ gas, which directly enters the microchannel reaction unit, to the BF ₃ gas, which is mixed in the mixing unit , is 100-10:0-90, and in the case of supplying BF ₃ gas to the mixing unit, any two of the BF ₃ gas, the olefin feedstock and the auxiliary feedstock are mixed and then mixed with the third component; preferably the BF ₃ gas and the auxiliary feedstock are mixed to form a complex and then mixed with the olefin feedstock, or the auxiliary feedstock and the olefin feedstock are mixed and then mixed with the BF ₃ gas, or the BF ₃ gas, the olefin feedstock and the auxiliary material are mixed simultaneously raw materials. 19. The method according to claim 9, in which the installation according to any one of claims is used to produce polyalphaolefins. 1-8.

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