CN100429325C - Method of eliminating and reclaiming metal form petroleum - Google Patents

Abstract

The invention relates to a method for removing and recovering metals from petroleum. Inorganic magnetic particles are used as the adsorbent, the adsorbent is fully contacted with crude oil, and the metal compounds in the crude oil are adsorbed by the magnetic particles at a temperature of 90°C-200°C. The crude oil after metal removal is collected, the magnetic particles adsorbed with metal are washed and desorbed with water, and the aqueous phase containing metal organic matter is removed. At the same time, it is evaporated to dryness to obtain oil residue containing metal organic compounds, and the oil residue is roasted at a temperature above 700°C to obtain a mixture of various metal oxides, and various metal elements are obtained through separation and reduction of the mixture. The invention can conveniently remove and recover metals from petroleum, especially to obtain rare and precious metals such as nickel and vanadium, with low cost, high efficiency, convenient separation of agent and oil, easy regeneration of adsorbent, simple operation, and effective utilization of petroleum resources. A new method with industrial applicability is provided. Among them, the yield of nickel metal can reach more than 80%, and the yield of vanadium metal can reach more than 70%.

Description

A method for removing and recovering metals from petroleum

technical field

The present invention relates to a method for removing and recovering metals from petroleum, specifically a method for removing and recovering metals from petroleum by adsorption with an adsorbent, especially a method for removing porphyrin metal compounds and recovering precious metals such as nickel and vanadium , also belongs to the effective use of petroleum resources.

Background technique

Petroleum is the most important energy source in the world in this century. The main components of petroleum are hydrocarbons, and there are a small amount of metal components in it. Currently, 45 kinds of metal elements have been identified in petroleum, which exist in different forms. Among them, Na, Ca, Mg and other alkali metals or alkaline earth metals mostly exist in the form of inorganic salts or naphthenates, while nickel and vanadium mostly exist in the form of porphyrin compounds. In the process of petroleum processing, Na, Ca, Mg, etc. can be removed by crude oil electric desalting equipment, but nickel and vanadium in the form of porphyrin compounds are not easy to remove, which will cause contamination of catalytic cracking catalysts, reduce the yield of light oil, and produce The quality deteriorates. Vanadium in fuel oil forms V ₂ O ₅ during the combustion process, forms eutectic on the surface, dissolves the protective oxide film on the metal surface, and accelerates the corrosion of the metal surface. Therefore, the removal of porphyrin metals in petroleum is of great significance to improve the quality of petroleum products.

At present, the methods for removing nickel, vanadium and other metals in petroleum include acid extraction, hydrogenation, chelation separation, solvent oil extraction and other methods. Acid extraction method: This method mainly uses hydrogen bromide-glacial acetic acid or hydrogen bromide-formic acid solution as the extraction solvent to extract porphyrin and metal porphyrin compounds, which are mainly used to analyze porphyrin compounds in petroleum. The oil loss in this process is large and pollutes the environment. Hydrogenation method: Since nickel and vanadium mainly exist in residual oil, the product yield and catalyst activity are seriously affected when hydrodesulfurization or catalytic cracking is performed, so some refineries have adopted hydrodemetallization technology. The key to this technology is to use a demetallization catalyst to hydrodecompose nickel, vanadium porphyrin and complex compounds, so that nickel and vanadium are deposited on the demetallization catalyst, thereby reducing the content of nickel and vanadium in the residual oil. The investment in the hydrodemetallization unit is huge, and the catalyst is difficult to regenerate, which makes it impossible to treat the spent catalyst. Chelation separation method: Some compounds can react with nickel, vanadium porphyrin and their complex compounds to form non-oil-soluble substances, which can be separated by physical methods to achieve the purpose of removing nickel and vanadium. However, it is difficult to find nickel and vanadium chelating agents with strong chelating ability. Solvent extraction method: Since nickel and vanadium in petroleum mostly exist in the form of porphyrin compounds, and porphyrin compounds can be miscible with organic solvents, nickel and vanadium porphyrin compounds can be extracted from petroleum with acetonitrile, DMF, etc., but This method is mostly used for analysis and cannot be industrialized. Nickel and vanadium porphyrin compounds are easy to associate with asphalt to form asphalt cementation ions, so nickel and vanadium mostly exist in asphaltenes. If the asphalt is removed, part of the nickel and vanadium can also be removed. Solvent deasphalting can only remove nickel and vanadium in residual oil with high asphalt content, and the investment and operation cost are high.

In addition, the utilization of hydrocarbons in petroleum has reached a very high level, and petroleum is used as raw material to process nearly 5,000 kinds of products such as gasoline, diesel oil, kerosene, paraffin, polyester, ethylene, and synthetic amines. However, the metal components contained in petroleum are generally considered to have no industrial value due to their small content, difficulty in separation, and high cost. The metals contained in petroleum, especially precious and rare metals, are important resources worth using. For example, the melting point of vanadium is 1910°C, it has good corrosion resistance and is easy to process. It is generally believed that the vanadium ore layer with a mining grade of not less than 0.10% has economic value. , and in petroleum residue, the content of sodium, vanadium and iron can reach 9%, nickel 6%, magnesium 1.9%, calcium 1.2%. Therefore, the recovery of metals from petroleum, especially precious and rare metals such as nickel and vanadium, will be of great significance. However, the existing methods for removing metals from petroleum require large investment, high operating costs, and difficult recovery, so that the profit margin for the recovery and reuse of metals after removal is very small. Therefore, it is necessary to find a method with high efficiency, simple method, low cost and industrial value for removing and recovering metals from petroleum.

Contents of the invention

The invention proposes a method for magnetic particle adsorption to remove metals in petroleum, which has high removal efficiency, low cost, simple operation, easy separation of adsorbent and oil, and proposes a method for recovering the removed metals, especially nickel, The method for rare and precious metals such as vanadium has high recovery rate and simple operation, and then obtains a method for removing and recovering metals from petroleum with industrial economic value.

The invention proposes a method for removing metals from petroleum. Inorganic magnetic particles are selected as the adsorbent, and the adsorbent is fully contacted with the crude oil. At a temperature of 90°C-200°C, the metal compounds in the crude oil are adsorbed by the magnetic particles, and the removed metals are collected. The crude oil after metal removal is washed and desorbed with water to the magnetic particles adsorbed with metal, and the aqueous phase containing metal organic matter is released.

The adsorption process of the above-mentioned adsorbent in contact with crude oil can be mixed contact adsorption under stirring conditions, that is, adding magnetic particles to crude oil, stirring and mixing evenly, wherein the weight percentage of magnetic particles and crude oil is 0.5%-10%, and under mixing conditions Let the magnetic particles adsorb the metals in the crude oil for 1-30 minutes, then filter and separate the magnetic particles adsorbed with metals, wash and desorb with water, filter and separate the magnetic particles, and remove the metal organic matter-containing aqueous phase.

The adsorption process of the above-mentioned adsorbent in contact with crude oil can adopt adsorption bed contact adsorption. Even if the crude oil passes through the adsorption bed layer equipped with magnetic particles as adsorbent, the temperature is above 90°C, the space velocity is 0.5-3.0h ^-1 , and the pressure is 0.2-0.6MPa, after the demetallization efficiency drops to 60% of the original, water is passed through to wash and desorb the adsorption bed, the adsorption bed is dried and regenerated for reuse, and the aqueous phase containing metal organic matter is collected and released.

For the above-mentioned adsorption bed contact adsorption, it is preferable to use two adsorption towers to switch the continuous operation mode.

A method for recovering metals from petroleum, using inorganic magnetic particles as the adsorbent, making the adsorbent fully contact with the crude oil, using magnetic particles to adsorb metal compounds in the crude oil at a temperature of 90°C-200°C, and magnetically absorbing the metal. The particles are washed and desorbed with water, the aqueous phase containing metal organic compounds is removed, evaporated to dryness to obtain oil residue containing metal organic compounds, and the oil residue is roasted at a temperature above 700°C to obtain a mixture of various metal oxides. After the mixture is sorted , Reduction to get each metal element.

The above-mentioned sorting to the mixture of multiple metal oxides adopts common method, as: separate various metal oxides with electromagnetic magnetic separator; The hydrogenation reduction method of the compound can obtain various metal elements.

The inorganic magnetic particle that the present invention adopts is the mixture of one or more in the following magnetic materials prepared by known method: (1) monometallic magnetic materials such as Fe, Co, Ni; (2) Nd-Fe-B, Fe-MB, Fe-MC, Fe-MN, Fe-MO (M is Zr, Hf, Nb, Ta, V and other alloy magnetic materials; (3) oxide magnetic materials, such as Fe ₃ O ₄ , γ-Fe ₂ O ₃ , Co ₃ O ₄ , Mn ₃ O ₄ and various ferrites (CoFe ₂ O ₄ , BaFe ₁₂ O _19, etc.); (4) Surface-wrapped and modified magnetic materials, such as using small organic molecules to modify the particle surface, Use organic polymers to modify the particle surface, use SiO ₂ to modify the particle surface or use other inorganic materials to modify the particle surface.

The metal compound adsorbed by the magnetic particles of the present invention may be adsorbed under the condition of an external magnetic field. Applying an external magnetic field in the adsorption area can strengthen the magnetism of the magnetic particles, thereby enhancing the adsorption force.

The effect of the present invention: the new method proposed by the present invention to adsorb and remove metals in petroleum with magnetic particles is easier than the existing chemical method for removing petroleum porphyrin metal compounds, and the removal efficiency is high, wherein the removal rate of porphyrin nickel is It can reach 90%, and the removal rate of porphyrin vanadium can reach 86%, and the operation is simple, the cost is low, the separation of solvent and oil is convenient, and the adsorbent is easy to regenerate, so as to recover metals from petroleum, especially the recovery of rare and precious materials such as nickel and vanadium. The metal recovery rate is high, and the recovery method is simple, wherein the nickel metal yield can reach more than 82%, and the vanadium metal yield can reach more than 79%, providing a new method with industrial practicability for the effective utilization of petroleum resources.

specific implementation plan

The present invention is further illustrated by examples below, but the present invention is not limited to these examples.

Embodiment 1: make adsorbent with single metal magnetic material Ni(P), Ni(B) alloy

Ni(P) and Ni(B) alloys can be easily prepared by known chemical deposition methods. The infiltration of P and B here can make Ni easy to form Ni grains during the deposition process. Ni crystal is a strong magnetic material. Use this magnetic material as adsorbent, add in the crude oil sample according to the mass ratio of the nanoparticles and the crude oil at 2% (the nickel content in the sample is 37 μg/g, the vanadium content is 250 μg/g), in a device with stirring, 90 Fully stir for 30 minutes at ℃ to make the magnetic particles fully adsorb the metal compounds in the crude oil, filter and separate the adsorbent, collect the crude oil after metal removal, and detect it with flame atomic absorption spectrophotometry. The porphyrin nickel removal rate can reach 80% % or more, the porphyrin vanadium removal rate can reach more than 75%. The adsorbent adsorbed with metal is washed with water 3 times the mass of the adsorbent, even if the adsorbed metal is desorbed from the magnetic particles, the magnetic particles and the water phase containing metal-organic substances are separated by filtration, and the water phase is evaporated to dryness to obtain oil containing metal-organic compounds The slag is roasted at 700°C to obtain a mixture containing various metal oxides. The metal oxides are separated in an electromagnetic magnetic separator, and the oxides are respectively passed through hydrogen at 500°C. Nickel is obtained by the usual hydrogenation reduction process. , Elemental vanadium metal. As determined by inductively coupled plasma emission spectrometry, the yield of nickel metal can reach more than 72%, and the yield of vanadium metal can reach more than 70%.

Embodiment 2: Fe-Si magnetic material is made adsorbent

Fe powder (purity 99.9%, initial particle size-200 mesh) and Si powder (purity 99.9%, initial particle size-200 mesh) are used in a ratio of 75:25 in atomic percentage. The experiment used high-energy planetary ball mill, vacuum ball mill jar and stainless steel ball produced by Nanjing University Instrument Factory. High-speed ball milling was performed with a ball-to-material ratio of 15:1 and a rotational speed of 200 r/min, and argon was used as a protective gas. Ball mill for 48h-98h, and then put the ball-milled powder in a tubular high-temperature furnace for annealing heat treatment under a hydrogen protective atmosphere. A composite Fe-Si powder is obtained. Make adsorbent with this magnetic material, pack into two tower-type adsorption beds, adopt the operation technology of common two tower switching, crude oil (crude oil is the same as embodiment 1) flows through the bed layer of the first tower, and temperature is more than 90 ℃, The space velocity is 3.0h ^-1 and the pressure is 0.6MPa. The crude oil after metal removal is collected from the outlet, and detected by flame atomic absorption spectrophotometry. The removal rate of porphyrin nickel can reach more than 86%, and the removal rate of porphyrin vanadium The removal rate can reach more than 81%. When the demetallization efficiency of the first tower drops to 60% of the original value, switch to the operation of the second tower. The first tower is reversely fed with water to desorb the adsorption bed, and then dried with air at 50°C to regenerate the adsorption bed for repeated use. Finally, the water phase containing metal oxides is removed and evaporated to dryness to obtain oil residues containing metal-organic compounds. The oil residues are treated with the same steps as in Example 1 to classify and recover metal elements, wherein the yield of nickel metal can reach more than 80%, and the yield of vanadium metal can reach 80%. Up to 73% or more.

Example 3: Alloy NdFeB magnetic material as adsorbent

The alloy with the composition of Nd _10.2 Pr ₃ Dy _0.5 Fe ₈₀ Al _0.3 B ₆ was melted in an induction furnace under an Ar atmosphere, and a rapid-quenching thick strip with a thickness of 200-300 μm was made by using the sheet casting (Strip2casting) technology, wherein the melting The body temperature is 1200-1500°C, and the roll speed is 1m/s. After absorbing hydrogen at room temperature, the thick tape is dehydrogenated in vacuum at 600°C, and is jet-milled to produce powder particles with an average particle size of about 5 μm. After being oriented and pre-pressed by a magnetic field (1.5T), it is put into a graphite mold for SPS sintering, and is prepared as High performance NdFeB permanent magnet material. Use the mass ratio of this magnetic material to crude oil to be 0.5%, fully stir at 90°C for 20 minutes, and adsorb metal compounds in the crude oil. The subsequent treatment steps are the same as in Example 1. The adsorbent is separated and washed with 3 times the mass of the adsorbent. Evaporate to dryness to obtain oil residue containing metal-organic compounds, and roast the oil residue at 700°C to obtain a mixture of metal oxides. The subsequent separation and hydroprocessing steps are the same as in Example 1. The yield can reach more than 70%, and the yield of vanadium metal can reach more than 70%.

Embodiment 4: oxide Fe ₃ O ₄ magnetic material as adsorbent

Nitrogen was passed through the distilled water used before the reaction for 30 minutes to remove oxygen in the water. Dissolve FeCl ₃ 6H ₂ O and FeCl ₂ 6H ₂ O in 250mL of distilled water at a ratio of 1.8:1, add an appropriate amount of complexing agent citric acid and dispersant polyethylene glycol, and transfer to 500mL in a four-neck flask, and then placed in a constant temperature water bath at 68°C. Slowly add 0.2mol/L precipitant NaOH dropwise until the system pH is ≥9.2. During the reaction, the stirrer stirred at 1500r/min, and the whole reaction process was carried out under the protection of nitrogen. Centrifuge the product, wash it alternately with ethanol solution and acetone several times to remove Na ⁺ , and finally wash it with 3 mol/L ammonium bicarbonate solution and dry it in a vacuum oven at 70°C for 8 hours to obtain magnetic Fe ₃ O ₄ powder. The mass ratio of the magnetic material to the crude oil is 2%, fully stirred at 180° C. for 30 minutes, and the porphyrin metal in the crude oil is adsorbed. The subsequent treatment steps are the same as in Example 1. The adsorbent is separated and washed with 3 times the mass of the adsorbent. Evaporate to dryness to obtain oil residue containing metal-organic compounds, and roast the oil residue at 700°C to obtain a mixture of metal oxides. The subsequent separation and hydroprocessing steps are the same as in Example 1. The yield can reach more than 80%, and the vanadium metal yield can reach more than 75%.

Embodiment 5: CoxFe ₃ -xO ₄ magnetic material as adsorbent

Ammonium oxalate is used as precipitant, chemically pure cobalt chloride and ferrous sulfate are used as raw materials, and the required raw materials are calculated according to Co _0.5 Fe _2.5 O ₄ , and the working solution (cobalt chloride, cobalt chloride, Mixed solution of ferrous sulfate) and precipitation solution (ammonium oxalate solution) were heated to 70°C, and then the working solution was slowly injected into the precipitation solution and kept stirring. After washing and drying, the materials were moved into a high-temperature furnace and heated to 850°C at a heating rate of 1°C/min and kept at this temperature for 215 hours; finally, these pre-burned micro-powder materials were respectively heated at 1260°C, 1280°C, 1300°C, After being kept at five temperatures of 1320°C and 1340°C for 2.5 hours, it was naturally cooled to room temperature in the air, so that the cobalt ferrite samples required for the experiment were obtained. The mass ratio of this magnetic material to the crude oil is 0.5%. Under the conditions of 180°C and an external 1.2T magnetic field, fully stir for 10 minutes to adsorb metal compounds in the crude oil. The subsequent treatment steps are the same as in Example 1. Wash with water of agent quality, evaporate the washing water to dryness to obtain oily residue containing metal-organic compounds, roast the oily residue at 700°C to obtain a mixture of metal oxides, and the subsequent separation and hydroprocessing steps are classified as in Example 1 Recover simple metals, in which the yield of nickel metal can reach more than 85%, and the yield of vanadium metal can reach more than 80%.

Example 6: Surface wrapped and modified magnetic material Fe ₃ O ₄ /SiO ₂ as adsorbent

Weigh an appropriate amount of _Fe3O4 nanoparticles and disperse them in absolute ethanol _, add a few drops of oleic acid, and then ultrasonically disperse for 10 minutes; transfer the dispersed solution into a 250mL three-necked flask, press n(TEOS):n( NH ₃ ·H ₂ O)=1:2, add TEOS and NH ₃ ·H ₂ O, stir for 3 hours; after the reaction is completed, under the condition of magnetic field attraction; wash the solution repeatedly with distilled water until the washed solution is no longer It becomes turbid; the obtained precipitate is vacuum-dried at 70°C, and finally ground to obtain the final composite particles. The mass ratio of this magnetic material to the crude oil is 2%, fully stirred at 90°C for 10 minutes, adsorbs the metal compound in the crude oil, separates the adsorbent and washes it with water 3 times the mass of the adsorbent, and evaporates the washing water to dryness to obtain the metal compound containing the metal organic compound. Oil residue, the oil residue is roasted at 700°C to obtain a mixture of metal oxides, the subsequent separation and hydrogenation steps are the same as in Example 1 to classify and recover metal elements, wherein the nickel metal yield can reach more than 75%, vanadium The metal yield can reach 72%. The adsorbent after water washing is purged and dried with nitrogen, and then used to adsorb metal compounds in fresh crude oil. The nickel metal yield can reach more than 72%, and the vanadium metal yield can reach more than 70%.

Embodiment 7: Ni(B) and Fe ₃ O ₄ composite magnetic material as adsorbent

The magnetic materials of Example 1 and Example 4 are mixed by grinding according to the mass ratio of 1:3, and the mass ratio of the crude oil is 0.5%, and stirred and mixed for 20 minutes at 180°C and an external 1.2T magnetic field to absorb the metal compound in the crude oil , the follow-up treatment steps are the same as in Example 1, the adsorbent is separated and washed with water of 3 times the mass of the adsorbent, and the washed water is evaporated to dryness to obtain oil residue containing metal organic compounds, and the oil residue is roasted at 700 ° C to obtain various metal oxides The mixture, the follow-up separation and hydroprocessing steps are the same as in Example 1 to classify and recover metal elemental substances, wherein the yield of nickel metal can reach more than 90%, and the yield of vanadium metal can reach more than 85%.

Example 8: CoxFe ₃ -xO ₄ and Fe ₃ O ₄ composite magnetic material as adsorbent

The magnetic materials of Example 4 and Example 5 were mixed by grinding according to the mass ratio of 2:3 to obtain a composite magnetic adsorbent. Use this magnetic material as an adsorbent, put it into a tower-type adsorption bed, adopt the same two-tower switching operation mode as in Example 2, and crude oil flows through the bed at a temperature of 150°C, a space velocity of 0.5h ^-1 , and a pressure of 0.2 MPa, the metal regeneration and recovery process is the same as in Example 2, the yield of nickel metal can reach more than 76%, and the yield of vanadium metal can reach more than 80%.

Claims (9)

1, a kind of method that from oil, removes metal, it is characterized in that, selecting the inorganic magnetic particle for use is sorbent material, crude oil is fully contacted with sorbent material, under 90 ℃ of-200 ℃ of temperature with the metallic compound in the magnetic particle absorption crude oil, collection removes the crude oil behind the metal, to being adsorbed with the magnetic particle washing desorb of metal, deviates from containing metal organism water.

2, method according to claim 1 is characterized in that, magnetic particle is one or more the mixture in the following magneticsubstance: (1) monometallic magneticsubstance; (2) alloy magnetic material, (3) oxidate magnetic material; (4) magneticsubstance of surface parcel modification.

3, method according to claim 2 is characterized in that, the monometallic magneticsubstance is selected from Fe, Co or Ni; Alloy magnetic material is selected from Nd-Fe-B, Fe-M-B, Fe-M-C, Fe-M-N or Fe-M-O, and wherein M represents Zr, Hf, Nb, Ta or V metallic element; Oxidate magnetic material is selected from Fe ₃O ₄, γ-Fe ₂O ₃, Co ₃O ₄, Mn ₃O ₄With ferrite CoFe ₂O ₄, BaFe ₁₂O ₁₉The magneticsubstance that the surface parcel is modified is selected from the employing organic molecule and modifies particle surface, adopts organic polymer to modify particle surface or adopt SiO ₂Modify the magneticsubstance of particle surface.

4, method according to claim 1, it is characterized in that, the adsorption process that sorbent material contacts with crude oil, be the mixing contact absorption under agitation condition, promptly in crude oil, add magnetic particle, mix, wherein magnetic particle and crude oil weight percent are 0.5%-10%, under mixing condition, make in the magnetic particle absorption crude oil metal 1-30 minute, refilter and isolate the magnetic particle that is adsorbed with metal, through the washing desorb, filter to isolate magnetic particle, deviate from containing metal organism water.

5, method according to claim 1 is characterized in that, the adsorption process that sorbent material contacts with crude oil adopts adsorption bed contact absorption, even crude oil is made the adsorption bed of sorbent material by magnetic particle is housed, temperature is more than 90 ℃, and air speed is 0.5-3.0h ^-1, pressure is 0.2-0.6MPa, after the demetalization decrease in efficiency is original 60%, feeds water adsorption bed is washed desorb, the regeneration of adsorption bed drying is reused, and deviates from the organic water of containing metal.

6, method according to claim 5 is characterized in that, adsorption bed contact absorption selects for use two adsorption towers to switch the operate continuously mode.

7, method according to claim 1 is characterized in that, magnetic particle absorption metallic compound is to adsorb adding under the magnetic field condition.

8, a kind of method that from oil, reclaims metal, it is characterized in that, deviate from containing metal organism water with the method for claim 1, its evaporate to dryness is obtained containing the metal-organic dregs of fat, with these dregs of fat in temperature roasting more than 700 ℃, obtain the mixture of multiple metal oxide, obtain each metal simple-substance through sorting and reduction to mixture.

9, method according to claim 8 is characterized in that, to the sorting of the mixture of multiple metal oxide, adopts the electromagnetic separator separation method; To the reduction that the metal oxide that obtains is opened in sorting, adopt the oxide compound hydrogenation reduction method.