CN108786687A - Photochemical reaction system based on micro- Chemical Engineering Technology - Google Patents

Abstract

A photochemical reaction system based on micro-chemical technology in the field of photochemical application technology, comprising: a multi-channel micro-reactor and an LED light strip, wherein: the multi-channel micro-reactor is provided with a group of reaction channels, and one end of the group of reaction channels is connected with a mixing chamber, The other end is connected with a collection chamber, and LED light strips are helically wound outside the reaction channel group; the reaction channel group is composed of several reaction channels in a circular array. The invention can combine the characteristics of photochemical conversion and micro-chemical technology to achieve high heat and mass transfer performance, obtain uniform illumination inside the reaction channel, and improve the yield and purity of products in the photochemical conversion process.

Description

Photochemical reaction system based on microchemical technology

technical field

The invention relates to a technology in the field of photochemical reaction, in particular to a photochemical reaction system based on microchemical technology.

Background technique

Photochemical conversion has attracted worldwide attention since the 1970s because of its environmental friendliness, milder reaction conditions compared with thermochemical reactions, and the ability to realize some reaction processes that are difficult to achieve in thermochemical conversion.

However, in the existing photoreaction technology, the internal illumination of the reactor is not uniform, which easily causes side reactions, and thus the reaction selectivity is low, which seriously affects the production efficiency; on the other hand, the energy utilization rate is low, the effective temperature control of the light source and the reaction system is difficult, and The amplification of the reaction process is also a difficult problem restricting the large-scale industrial application of photochemical transformation.

Contents of the invention

Aiming at the above-mentioned deficiencies in the prior art, the present invention proposes a photochemical reaction system based on micro-chemical technology, which can combine the characteristics of photochemical conversion and micro-chemical technology to achieve higher heat and mass transfer performance and improve the production efficiency of the photochemical conversion process. yield and purity.

The present invention is achieved through the following technical solutions:

The invention comprises: a multi-channel microreactor and an LED light strip, wherein: the multi-channel microreactor is provided with a reaction channel group, one end of the reaction channel group is connected with a mixing chamber, and the other end is connected with a collection chamber, and the outer side of the reaction channel group is spirally wound with LED light strip;

The reaction channel group is composed of several circular array reaction channels.

The reaction channel is a capillary; preferably, the inner diameter of the capillary is 0.25-3 mm.

The mixing chamber is provided with several feed ports and capillary discharge ports, the number of capillary discharge ports is the same as the number of reaction channels, and the positions correspond to the reaction channels one by one.

The LED light strip is supported by a plurality of ring-shaped light source fixing rods to ensure good light intensity distribution inside the reaction channel and increase productivity; both ends of the light source fixing rods are fixedly connected to the mixing chamber and the collecting chamber respectively.

The number of said light source fixing rods is not less than 3.

The light source of the LED light strip is ultraviolet light with a wavelength range of 200-400nm or visible light with a wavelength range of 400-760nm; the light source can be replaced according to the requirements of different reaction systems.

The material of the reaction channel is FEP, PFA, ETFE, ECTFE and other plastic polymer materials with light transmission; the rest of the structural materials can be inorganic materials, such as stainless steel, copper, zinc, aluminum, silicon carbide or plexiglass; Different materials of parts can choose corresponding fixed connection method as welding or pressure fastening.

Preferably, the LED light strip is covered with a heat exchange sleeve to enhance the heat exchange efficiency, remove the heat generated by the light source in a timely manner, and further improve the life of the light source and the yield of the photochemical conversion process.

The heat exchange medium in the heat exchange sleeve is one or more mixed gases of low temperature air, low temperature nitrogen and low temperature argon.

technical effect

Compared with the prior art, the present invention combines the characteristics of photochemical conversion and micro-chemical technology, achieves higher mass transfer and heat transfer rates, and at the same time realizes good light intensity distribution, high-efficiency photoelectric conversion efficiency and larger Throughput operation improves the yield and purity of products in the photochemical conversion process, reduces energy consumption, and is suitable for a variety of photochemical reaction systems; at the same time, the internal structure of the system is simple, and each component can be installed and disassembled independently, which is convenient for processing and manufacturing.

Description of drawings

Fig. 1 is a front view of the overall structure of the present invention with a heat exchange sleeve installed;

Fig. 2 is a structural front view of the present invention without a heat exchange sleeve installed;

Fig. 3 is a front view of the internal structure of the present invention without heat exchange sleeve and LED light strip;

Fig. 4 is A-A sectional view among Fig. 2;

In the figure: mixing chamber 1, collecting chamber 2, heat exchange sleeve 3, LED light strip 4, reaction channel 5, light source fixing rod 6.

Detailed ways

The embodiments of the present invention are described in detail below. This embodiment is implemented on the premise of the technical solution of the present invention, and detailed implementation methods and specific operating procedures are provided, but the protection scope of the present invention is not limited to the following implementation example.

Example 1

As shown in Fig. 1, Fig. 2 and Fig. 3, the present embodiment includes: a multi-channel microreactor and an LED light strip 4, wherein: the multi-channel microreactor is provided with a reaction channel group, and one end of the reaction channel group is connected with a mixing chamber 1 . The other end is connected to a collection chamber 2, and the LED light strip 4 is spirally wound on the outside of the reaction channel group, and a heat exchange sleeve 3 is arranged outside the LED light strip 4;

As shown in FIG. 4 , the reaction channel group is composed of 25 reaction channels 5 in a circular array.

The reaction channel 5 is a capillary; preferably, the inner diameter of the capillary is 0.75mm, the length is 2.5m, and the material is PFA.

The mixing chamber 1 is provided with two feeding ports and 25 capillary outlets.

Preferably, the LED light strip 4 is supported by three light source fixing rods 6 in an annular array, and the two ends of the light source fixing rods 6 are fixedly connected to the mixing chamber 1 and the collecting chamber 2 respectively.

The LED light strip 4 emits visible light with a characteristic wavelength of 530nm and a power of 60W.

Preferably, the heat exchange medium in the heat exchange sleeve 3 is low-temperature air.

In this embodiment, the above-mentioned system is used to carry out the photocatalytic reaction of benzenethiol: oxygen is used as the gas phase, and the methanol solution containing thiophenol, tetramethylethylenediamine and eosin is used as the liquid phase, and the reaction residence time is 90s. The collected product Diphenyl disulfide, its yield is 90%.

Example 2

As shown in Fig. 2 and Fig. 3, present embodiment comprises: multi-channel microreactor and LED light band 4, wherein: multi-channel microreactor is provided with reaction channel group, and one end of reaction channel group is connected with mixing chamber 1, the other end It is connected with a collection cavity 2, and an LED light strip 4 is spirally wound on the outside of the reaction channel group;

As shown in FIG. 4 , the reaction channel group is composed of 25 reaction channels 5 in a circular array.

The reaction channel 5 is a capillary; preferably, the inner diameter of the capillary is 1.59mm, the length is 4.1m, and the material is FEP.

The mixing chamber 1 is provided with two feeding ports and 25 capillary outlets.

Preferably, the LED light strip 4 is supported by three light source fixing rods 6 in an annular array; both ends of the light source fixing rods 6 are fixedly connected to the mixing chamber 1 and the collecting chamber 2 respectively.

The LED light strip 4 emits ultraviolet light with a wavelength of 365nm and a power of 300W.

In this embodiment, the above-mentioned system is used to carry out photocatalytic dimerization of maleic anhydride: the gas phase is nitrogen, the liquid phase is maleic anhydride solution with a mass fraction of 5%, the solvent is ethyl acetate, and the reaction residence time is 19.1min. The product is collected Cyclobutanetetracarboxylic dianhydride, the yield is 30%.

Example 3

As shown in Fig. 1, Fig. 2 and Fig. 3, the present embodiment includes: a multi-channel microreactor and an LED light strip 4, wherein: the multi-channel microreactor is provided with a reaction channel group, and one end of the reaction channel group is connected with a mixing chamber 1 . The other end is connected to a collection chamber 2, and the LED light strip 4 is spirally wound on the outside of the reaction channel group, and a heat exchange sleeve 3 is arranged outside the LED light strip 4;

As shown in FIG. 4 , the reaction channel group is composed of 25 reaction channels 5 in a circular array.

The reaction channel 5 is a capillary; preferably, the inner diameter of the capillary is 1.59mm, the length is 4.1m, and the material of the capillary is FEP.

The mixing chamber 1 is provided with two feeding ports and 25 capillary outlets.

Preferably, the LED light strip 4 is supported by three light source fixing rods 6 in an annular array; both ends of the light source fixing rods 6 are fixedly connected to the mixing chamber 1 and the collecting chamber 2 respectively.

The LED light strip 4 emits ultraviolet light with a characteristic wavelength of 365nm and a power of 300W.

Preferably, the heat exchange medium in the heat exchange sleeve 3 is low temperature nitrogen.

In this embodiment, the above-mentioned system is used to carry out photocatalytic dimerization of maleic anhydride: the gas phase is nitrogen, the liquid phase is maleic anhydride solution with a mass fraction of 5%, the solvent is ethyl acetate, and the reaction residence time is 19.1min. The product is collected Cyclobutane tetracarboxylic dianhydride, its productive rate is 42%;

In the prior art, the high-pressure mercury lamp is usually set in the center of the tank reactor as a light source: three 200W high-pressure mercury lamps arranged in an equilateral triangle are set in the central area of the tank reactor, emitting ultraviolet light with a characteristic wavelength of 365nm , under the same reaction conditions, using low-temperature nitrogen for heat exchange, the heat exchange rate is twice that of this example, and the yield is only 20%; if the power of a single high-pressure mercury lamp is increased to 600W, the reaction light time needs to be increased to 1 hour , the yield is only 10%.

Claims (9)

1. a kind of photochemical reaction system based on micro- Chemical Engineering Technology, which is characterized in that including：Multichannel microreactor and LED Light belt, wherein：Multichannel microreactor is equipped with reaction channel group, and reaction channel group one end is connected with mixing chamber, other end connection There are collecting chamber, reaction channel group's outer helical to be wound with LED light strip；

The reaction channel group is made of the reaction channel of several annular arrays.

2. the photochemical reaction system according to claim 1 based on micro- Chemical Engineering Technology, characterized in that the reaction is logical Road is capillary, and capillary inner diameter is 0.25~3mm.

3. the photochemical reaction system according to claim 2 based on micro- Chemical Engineering Technology, characterized in that the reaction channel Material be the thermoplastic polymer material with translucency such as FEP, PFA, ETFE, ECTFE.

4. the photochemical reaction system according to claim 2 based on micro- Chemical Engineering Technology, characterized in that the mixing chamber Equipped with several feed inlets and capillary discharge port, capillary discharge port quantity is identical as reaction channel quantity, position with react Channel corresponds.

5. the photochemical reaction system according to claim 1 based on micro- Chemical Engineering Technology, characterized in that the LED light Band by the light source fixed rod support of several annular arrays, fix with mixing chamber, collecting chamber respectively by the both ends of the light source fixed link Connection.

6. the photochemical reaction system according to claim 5 based on micro- Chemical Engineering Technology, characterized in that the light source is solid Fixed pole quantity is no less than 3.

7. the photochemical reaction system according to claim 5 based on micro- Chemical Engineering Technology, characterized in that the LED light The visible light of 400~760nm of ultraviolet light or wave-length coverage with 200~400nm of launch wavelength range.

8. the photochemical reaction system according to claim 5 based on micro- Chemical Engineering Technology, characterized in that the LED light Band outer cover is equipped with heat exchange sleeve.

9. the photochemical reaction system according to claim 8 based on micro- Chemical Engineering Technology, characterized in that the heat exchange sleeve In heat transferring medium be Cryogenic air, low temperature nitrogen and low temperature argon gas in one or more mixed gas.