Catalyst for cold hydrogenation reaction and preparation method thereof

Abstract

The invention discloses a catalyst for a cold hydrogenation reaction and a preparation method thereof, and the method comprises the following steps: 1) in a non-oxidizing atmosphere, a catalyst precursor is heated to a gas-phase substance, the gas-phase substance is mixed with a porous catalyst carrier, the catalyst precursor comprises a main catalyst precursor, and the main catalyst precursor is copper chloride; and 2) diffusing the gas-phase substance into a porous catalyst carrier, adsorbing, and cooling to obtain the catalyst for the cold hydrogenation reaction after the adsorption is completed. The catalyst is mainly composed of a carrier and a catalyst active component, the active component is a multi-metal silicide formed by an in-situ gas phase loading-reaction, the catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size, high active component content and large site number, in a fluidized bed reactor, the adsorption and reaction of hydrogen and silicon tetrachloride are promoted, and the catalytic activity of the catalyst is improved. Therefore, the conversion rate of silicon tetrachloride is improved, the utilization rate of the active components is improved, unnecessary waste of the active components is reduced, and the cost of the catalyst is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of polysilicon, and in particular relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. Background Art

[0002] Against the backdrop of global warming and the depletion of fossil energy, the development and utilization of renewable energy has received increasing attention from the international community. Zero-carbon emission "green electricity" has ushered in unprecedented development opportunities, which has greatly promoted the rapid development of polysilicon and photovoltaic industries. Trichlorosilane is the basic material for the preparation of high-purity polysilicon. It is generally prepared by synthesis (reaction of silicon powder and hydrogen chloride) and cold hydrogenation (silicon powder, hydrogen and by-product silicon tetrachloride). Among them, the cold hydrogenation reaction realizes the recovery and reuse of silicon tetrachloride by-products, which is an important way to reduce silicon consumption, chlorine consumption, alkali consumption and polysilicon preparation costs. Studies have shown that catalysts can not only effectively improve the selectivity of trichlorosilane in the synthesis reaction, but also promote the conversion of silicon tetrachloride during the cold hydrogenation reaction.

[0003] At present, the cold hydrogenation catalyst used in the industry is mainly CuCl. During the reaction, cuprous chloride reacts with silicon powder in a fluidized bed to generate a silicon-copper phase catalytic active body in situ; the silicon-copper phase active body adsorbs silicon tetrachloride and hydrogen to react to form trichlorosilane and hydrogen chloride, desorbs, and then performs the above-mentioned adsorption-reaction-desorption cycle. However, the main problems of cuprous chloride catalyst during use are: in the fluidized bed reactor, the particle size of cuprous chloride gradually decreases. Due to the limitation of the fluidized bed filtration system, the small-sized cuprous chloride cannot be fully and effectively utilized and flows into the back-end system, and is abandoned as waste treatment, resulting in a high catalyst unit consumption. There are also methods that use metal elements as raw materials, and the metal silicide powder prepared by induction melting-rapid solidification or mechanical alloying has the characteristics of uniform organization, fine grains, and high defect density, but the alloy powder has a small particle size and is easy to lose. In addition, during the catalytic reaction, only the outer surface of the alloy powder can be used, the effective surface area is small, and the catalyst utilization rate is low.

[0004] In recent years, the industry has developed supported catalysts, which have significantly lower unit consumption compared to pure cuprous chloride catalysts. Supported catalysts are mainly prepared by two methods, namely, impregnation and powder mixing / molding / calcination, and the carrier is generally a porous material. Since the active component cuprous chloride is slightly soluble in water, high-concentration hydrochloric acid or ammonia water is required as a solvent when preparing cuprous chloride supported catalysts by impregnation. The main problems are as follows: (1) Both hydrochloric acid and ammonia water are hazardous chemicals. Large-scale use poses a major safety hazard and pollutes the environment; (2) Hydrochloric acid is a highly corrosive substance and is prone to corroding equipment during drying and calcination; (3) Due to solubility, the active component loading is limited during a single impregnation, affecting the final catalyst activity; (4) During the active component impregnation process, when the impregnation liquid submerges the pores, the air in the pores cannot be discharged in time, causing local pressure to rise and eventually causing the carrier to break. When the catalyst is prepared by the powder mixing / molding / calcination method, due to the low melting point of cuprous chloride (430°C), the sintering temperature is too low, the strength of the prepared catalyst is low, and it is easy to wear, break, and lose in the cold hydrogenation fluidized bed. If the sintering temperature is too high, the active component cuprous chloride is easy to turn into liquid phase and lose. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a catalyst for cold hydrogenation reaction and a preparation method thereof in view of the above-mentioned deficiencies in the prior art. The catalyst prepared by the method has the characteristics of large specific surface area, wear resistance, moderate particle size, high content of active components and large number of sites.

[0006] The technical solution adopted to solve the technical problem of the present invention is to provide a method for preparing a catalyst for cold hydrogenation reaction, comprising the following steps:

[0007] 1) In a non-oxidizing atmosphere, a catalyst precursor is heated to a gas phase, and the gas phase is mixed with a porous catalyst carrier, wherein the catalyst precursor comprises: a main catalyst precursor, and the main catalyst precursor is cupric chloride;

[0008] 2) The gas phase diffuses into the porous catalyst carrier and is adsorbed. After the adsorption is completed, it is cooled to obtain a catalyst for the cold hydrogenation reaction.

[0009] Preferably, the catalyst precursor further includes: a promoter precursor, and the promoter precursor is at least one of zinc chloride, nickel chloride and aluminum chloride.

[0010] Preferably, the mass proportion of the main catalyst precursor in the catalyst precursor is 70-90%, and the mass proportion of the co-catalyst precursor is 10-30%.

[0011] Preferably, in the catalyst for the cold hydrogenation reaction, the mass content of the metal element in the main catalyst is 15-25%, and the mass content of the metal element in the co-catalyst is 5-15%.

[0012] Preferably, the catalyst has a particle size of 0.5 to 2.2 mm, a length of 0.2 to 1.2 mm, and a specific surface area of ​​60 m 2 / g.

[0013] Preferably, the heating method in step 1) is any one of plasma heating, microwave heating, thermal conduction heating and radiation heating.

[0014] Preferably, the heating method in step 1) is plasma heating, and the power of the plasma heating is 10 to 40 kW.

[0015] Preferably, the heating temperature in step 1) is 500-1000°C.

[0016] Preferably, the step 2) is carried out under a reducing atmosphere.

[0017] Preferably, the reducing steam used in the reducing atmosphere is a small molecule organic substance, and the small molecule organic substance is any one of methane, ethane, methanol, ethanol, ether, dimethyl ether, formaldehyde, and acetone.

[0018] Preferably, the method for preparing the catalyst for the cold hydrogenation reaction further comprises the following steps: preparation of a porous catalyst carrier, specifically:

[0019] The first step is mixing: mixing the carrier raw material, silicon powder, pore-forming agent and adhesive according to a preset ratio;

[0020] Step 2: Forming: Use the extrusion method to form the mixture and dry it;

[0021] Step 3: calcination: calcining the catalyst carrier prepared in step 2 under vacuum or nitrogen atmosphere;

[0022] Step 4: Pore formation: The catalyst carrier prepared in the third step is cleaned in water solvent and ultrasonic conditions to remove the pore-forming agent, form pores, and dry to obtain a porous catalyst carrier with a well-developed pore structure for use.

[0023] Preferably, in the first step, the components in the mixture are as follows: the mass fraction of the carrier raw material is 45-80%, the mass fraction of the silicon powder is 5-25%, the mass fraction of the adhesive is 10-20%, and the mass fraction of the pore former is 5-10%.

[0024] Preferably, the carrier raw material is clay mineral and / or fly ash;

[0025] Silicon powder is bag dust removal powder produced in the polysilicon reduction process or cold hydrogenation process, and its particle size is less than 100 mesh;

[0026] The adhesive is polyvinyl alcohol, stearic acid, stearate or a mixture of two thereof;

[0027] The pore-forming agent is one or a mixture of alkali metal and / or alkaline earth metal chlorides, and the particle size is less than 100 meshes.

[0028] Preferably, the carrier raw materials are clay minerals and fly ash, and the mass ratio of clay minerals to fly ash is (1:5) to (5:1).

[0029] Preferably, the clay mineral is one or a mixture of montmorillonite, loess, palygorskite, diatomaceous earth, kaolin, and has a particle size of less than 100 mesh.

[0030] Preferably, the pore former is sodium chloride or potassium chloride.

[0031] Preferably, in the first step, the mixing step is specifically ball milling mixing under an inert atmosphere, the rotation speed of the ball mill used for ball milling is 200 to 400 r / min, and the ball milling time is 2 to 12 h.

[0032] Preferably, in the second step, the drying temperature is 60-150°C.

[0033] Preferably, in the third step, the calcination temperature is 600-750° C. and the calcination time is 2-12 hours.

[0034] The present invention also provides a catalyst for cold hydrogenation reaction, which is obtained by the above preparation method.

[0035] The catalyst prepared by the present invention has a porosity greater than 20% and a specific surface area of ​​≥60m 2 / g, the metal element loading is greater than 20%. When the hydrochlorination temperature is 500-550°C, the catalytic conversion efficiency of silicon tetrachloride is greater than or equal to 28.5%.

[0036] The present invention selects ultrafine catalyst carrier, pore former and silicon powder as raw materials, adopts ball milling mixing-calcination-pore forming method to prepare porous catalyst carrier with large specific surface area, and adopts gas phase loading-in-situ reaction to form multi-metal silicide active intermediate to finally prepare catalyst. The invention has the following advantages: (1) using ultrafine powder as raw material and subjecting it to ball milling treatment is beneficial to increasing the specific surface area of ​​micropores and active components in the catalyst, and is beneficial to increasing the contact-reaction area between the active precursor and the ultrafine silicon powder; (2) adopting extrusion molding-calcination to prepare a high-strength carrier, using water solvent and ultrasonic cleaning to remove the pore-forming agent, form pores, and prepare a catalyst carrier with well-developed and uniformly distributed pores and good wear resistance, thereby reducing the escape of the catalyst and extending the service life of the catalyst; (3) compared with liquid and solid phase compounds, gas phase compounds have stronger diffusivity in the pores, strengthen the reaction with ultrafine silicon powder pieces, thereby increasing the active sites, and promoting the adsorption and reaction of silicon tetrachloride and hydrogen in the cold hydrogenation reaction process; (4) adopting a co-catalyst and a reducing atmosphere is beneficial to removing oxygen atoms on the surface of ultrafine silicon powder, realizing the valence state transformation of the main catalyst precursor, strengthening diffusion and electron transfer, and promoting the formation of active nano-active intermediates; (5) the induction period of the cold hydrogenation reaction can be shortened and the conversion rate of silicon tetrachloride can be improved.

[0037] The invention relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst mainly consists of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size, high active component content and large number of sites. In a fluidized bed reactor, the catalyst is conducive to promoting the adsorption and reaction of hydrogen and silicon tetrachloride, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of the active component due to too small particle size, improving the utilization rate of the active component, reducing unnecessary waste of the active component and reducing the cost of the catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a flow chart of a method for preparing a catalyst for a cold hydrogenation reaction in Example 2;

[0039] Figure 2 A schematic structural diagram of an apparatus used in a method for preparing a catalyst for a cold hydrogenation reaction.

[0040] Among them: 1-from the reducing gas storage tank; 2-fixed bed reactor; 3-the first valve; 4-the second valve; 5-mixing tank, 6-from the inert gas storage tank, 7-the third valve, 8-the fourth valve, 9-the fifth valve, 10-the first heater, 11-the second heater, 12-from the main catalyst precursor storage tank, 13-from the auxiliary catalyst precursor storage tank. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0042] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0043] In the description of this patent, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this patent and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this patent.

[0044] In the description of this patent, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be fixedly connected or set, or it can be detachably connected or set, or connected or set in one piece. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0045] Example 1

[0046] This embodiment provides a method for preparing a catalyst for a cold hydrogenation reaction, comprising the following steps:

[0047] 1) In a non-oxidizing atmosphere, a catalyst precursor is heated to a gas phase, and the gas phase is mixed with a porous catalyst carrier, wherein the catalyst precursor comprises: a main catalyst precursor, and the main catalyst precursor is cupric chloride;

[0048] 2) The gas phase diffuses into the porous catalyst carrier and is adsorbed. After the adsorption is completed, it is cooled to obtain a catalyst for the cold hydrogenation reaction.

[0049] This embodiment also provides a catalyst for cold hydrogenation reaction, which is obtained by the above-mentioned preparation method.

[0050] The present embodiment relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst is mainly composed of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size, high active component content, and a large number of sites. In a fluidized bed reactor, it is beneficial to promote the adsorption and reaction of hydrogen and silicon tetrachloride, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of active components due to too small particle size, improving the utilization rate of active components, reducing unnecessary waste of active components, and reducing the cost of the catalyst.

[0051] Example 2

[0052] This embodiment provides a method for preparing a catalyst for a cold hydrogenation reaction, comprising the following steps:

[0053] 1) In a non-oxidizing atmosphere, a catalyst precursor is heated to a gas phase, and the gas phase is mixed with a porous catalyst carrier, wherein the catalyst precursor comprises: a main catalyst precursor, and the main catalyst precursor is cupric chloride;

[0054] 2) The gas phase diffuses into the porous catalyst carrier and is adsorbed. After the adsorption is completed, it is cooled to obtain a catalyst for the cold hydrogenation reaction.

[0055] Preferably, the catalyst precursor further includes: a promoter precursor, and the promoter precursor is at least one of zinc chloride, nickel chloride and aluminum chloride.

[0056] Preferably, the mass proportion of the main catalyst precursor in the catalyst precursor is 70-90%, and the mass proportion of the co-catalyst precursor is 10-30%.

[0057] Preferably, the metal element content of the main catalyst in the cold hydrogenation reaction catalyst is 15-25% by mass, and the metal element content of the co-catalyst is 5-15% by mass. The catalyst provided in this embodiment is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst.

[0058] Preferably, the catalyst has a particle size of 0.5 to 2.2 mm, a length of 0.2 to 1.2 mm, and a specific surface area of ​​60 m 2 / g.

[0059] Preferably, the heating method in step 1) is any one of plasma heating, microwave heating, thermal conduction heating and radiation heating.

[0060] Preferably, the heating method in step 1) is plasma heating, and the power of the plasma heating is 10 to 40 kW.

[0061] Preferably, the heating temperature in step 1) is 500-1000°C.

[0062] Preferably, the step 2) is carried out under a reducing atmosphere.

[0063] Preferably, the reducing steam used in the reducing atmosphere is a small molecule organic substance, and the small molecule organic substance is any one of methane, ethane, methanol, ethanol, ether, dimethyl ether, formaldehyde, and acetone.

[0064] Preferably, the method for preparing the catalyst for the cold hydrogenation reaction further comprises the following steps: preparation of a porous catalyst carrier, specifically:

[0065] The first step is mixing: mixing the carrier raw material, silicon powder, pore-forming agent and adhesive according to a preset ratio;

[0066] Step 2: Forming: Use the extrusion method to form the mixture and dry it;

[0067] Step 3: calcination: calcining the catalyst carrier prepared in step 2 under vacuum or nitrogen atmosphere;

[0068] Step 4: Pore formation: The catalyst carrier prepared in the third step is cleaned in water solvent and ultrasonic conditions to remove the pore-forming agent, form pores, and dry to obtain a porous catalyst carrier with a well-developed pore structure for use.

[0069] Preferably, in the first step, the components in the mixture are as follows: the mass fraction of the carrier raw material is 45-80%, the mass fraction of the silicon powder is 5-25%, the mass fraction of the adhesive is 10-20%, and the mass fraction of the pore former is 5-10%. The silicon powder is ultrafine silicon powder.

[0070] Preferably, the carrier raw material is clay mineral and / or fly ash;

[0071] Silicon powder is bag dust removal powder produced in the polysilicon reduction process or cold hydrogenation process, and its particle size is less than 100 mesh;

[0072] The adhesive is polyvinyl alcohol, stearic acid, stearate or a mixture of two thereof;

[0073] The pore-forming agent is one or a mixture of alkali metal and / or alkaline earth metal chlorides, and the particle size is less than 100 meshes.

[0074] Preferably, the carrier raw materials are clay minerals and fly ash, and the mass ratio of clay minerals to fly ash is (1:5) to (5:1).

[0075] Preferably, the clay mineral is one or a mixture of montmorillonite, loess, palygorskite, diatomaceous earth, kaolin, and has a particle size of less than 100 mesh.

[0076] Preferably, the pore former is sodium chloride or potassium chloride.

[0077] Preferably, in the first step, the mixing step is specifically ball milling mixing under an inert atmosphere, the rotation speed of the ball mill used for ball milling is 200 to 400 r / min, and the ball milling time is 2 to 12 h.

[0078] Preferably, in the second step, the drying temperature is 60-150°C.

[0079] Preferably, in the third step, the calcination temperature is 600-750° C. and the calcination time is 2-12 hours.

[0080] like Figure 2 As shown, this embodiment provides a device for preparing a catalyst for a cold hydrogenation reaction, comprising:

[0081] The fixed bed reactor 2 is used to introduce the gas phase formed by gasification of the catalyst precursor and the porous catalyst carrier, and the gas phase diffuses into the porous catalyst carrier for adsorption. After the adsorption is completed, it is cooled to obtain the catalyst for the cold hydrogenation reaction;

[0082] From the reducing gas storage tank 1, connected to the fixed bed reactor, the reducing gas storage tank 1 is used to store the reducing gas;

[0083] A mixing tank 5 is connected to the fixed bed reactor and is used to mix the gas phase formed by gasification of the catalyst precursor and the porous catalyst carrier;

[0084] A first heater 10 is connected to the mixing tank 5, and the first heater 10 is used to heat the main catalyst precursor;

[0085] A second heater 11 is connected to the mixing tank 5, and the second heater 11 is used to heat the main catalyst precursor;

[0086] From the main catalyst precursor storage tank 12, connected to the first heater 10, the main catalyst precursor storage tank 12 is used to store the main catalyst precursor;

[0087] From the co-catalyst precursor storage tank 13, connected to the second heater 11, the co-catalyst precursor storage tank 13 is used to store the co-catalyst precursor;

[0088] From the inert gas storage tank 6, connected to the mixing tank 5, the inert gas storage tank 6 is used to store the inert gas.

[0089] A first valve 3 is provided on the connecting pipe between the reducing gas storage tank 1 and the fixed bed reactor 2;

[0090] A second valve 4 is provided on the connecting pipe between the fixed bed reactor 2 and the third valve 7;

[0091] A third valve 7 is provided on the connecting pipe between the inert gas storage tank 6 and the mixing tank 5;

[0092] A fourth valve 8 is provided on the connecting pipe between the first heater 10 and the mixing tank 5;

[0093] A fifth valve 9 is provided on the connecting pipe between the second heater 11 and the mixing tank 5 .

[0094] This embodiment also provides a catalyst for cold hydrogenation reaction, which is obtained by the above-mentioned preparation method.

[0095] After the implementation of this embodiment, the following beneficial effects are achieved:

[0096] (1) The catalyst particle size and fluidized bed filtration system are not restricted, which avoids the escape of incompletely utilized catalysts, which ultimately leads to low catalyst utilization and high catalyst unit consumption;

[0097] (2) Increase the effective specific surface area of ​​the catalyst, increase the adsorption sites and reactive sites of silicon tetrachloride and hydrogen, and improve the energy-enhancing conversion rate;

[0098] (3) Promote the diffusion of active components in the inner and outer pores of the catalyst and increase the loading of active components;

[0099] (4) Reduce the impact of harmful solvents such as hydrochloric acid and ammonia water during catalyst preparation, improve catalyst strength, and reduce safety hazards.

[0100] (5) Reduce the induction period of cold hydrogenation reaction and accelerate the reaction rate.

[0101] like Figure 1 As shown, specifically, the catalyst in this embodiment is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The catalyst is prepared using the above-mentioned device, and the preparation method includes the following steps:

[0102] The first step: weigh 500g of diatomaceous earth, 500g of fly ash, 300g of ultrafine silica powder, 120g of pore-forming agent, and 300g of adhesive, wherein the particle size of the diatomaceous earth, fly ash, ultrafine silica powder and pore-forming agent is 100-325 mesh, the pore-forming agent is sodium chloride, and the adhesive is sodium stearate, mix the above raw materials, and ball mill under an inert atmosphere, the ball mill speed is 250r / min, and the ball milling time is 6h;

[0103] Step 2: Extruding the mixture obtained in the first step into strips and drying them. The obtained strips have a diameter of 0.5 mm and a length of 0.3-0.8 mm. The drying temperature is 100°C.

[0104] Step 3: calcining the catalyst carrier prepared in the second step under nitrogen atmosphere at a temperature of 690°C for 5 hours;

[0105] Step 4: Clean the catalyst carrier obtained in the third step in water solvent and ultrasonic conditions to remove the pore-forming agent, form pores, and dry to obtain a catalyst carrier with a developed pore structure for use.

[0106] Step 5: Add 500 g of the porous catalyst carrier to the fixed bed reactor 2, open the second valve 4 and the third valve 7, and fully replace the fixed bed reactor with an inert gas, wherein the inert gas is nitrogen;

[0107] Step 6: Weigh 440g of copper chloride and add it to the first heater 10, weigh 30g of zinc chloride and 30g of aluminum chloride and add them to the second heater 11, turn on the first heater and the second heater, adjust the heating power of the first heater and the second heater to 40kw and 10kw respectively, heat and vaporize the catalyst precursor, turn on the inert gas storage tank 6, pass the carrier into the first heater and the second heater, and fully mix the main catalyst precursor and the co-catalyst precursor in the mixing tank 5;

[0108] Step 7: Open the second valve 4 and the first valve 3, and at the same time, keep the first heater and the second heater open, and continue to introduce inert gas therein, so that the catalyst precursor steam and the reducing steam pass through the fixed bed reactor, fully contact with the porous catalyst carrier, and undergo adsorption reaction. The tail gas is circulated into the mixing tank. The adsorption reaction time is 8 hours, and the reducing steam is ethanol steam.

[0109] Step 8: After the adsorption-reaction is completed, inert gas is used for cooling to obtain the catalyst for cold hydrogenation reaction, which is packaged for standby use.

[0110] The catalyst surface area is 83m 2 / g, porosity 19.5%, equivalent particle size range 0.35 ~ 1.01mm, main catalyst metal element content of 17.9%, co-catalyst metal element content of 2.9%.

[0111] The catalyst prepared in this embodiment is used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature is 500-550° C., the catalytic conversion efficiency of silicon tetrachloride is 29.8%, and the cyclic use is 144 hours.

[0112] In this embodiment, ultrafine catalyst carrier, pore former and silicon powder are selected as raw materials, and a ball milling mixing-calcination-pore forming method is adopted to prepare a porous catalyst carrier with large specific surface area, and a gas phase loading-in-situ reaction is adopted to form a multi-metal silicide active intermediate to finally prepare a catalyst. The invention has the following advantages: (1) using ultrafine powder as raw material and subjecting it to ball milling treatment is beneficial to increasing the specific surface area of ​​micropores and active components in the catalyst, and is beneficial to increasing the contact-reaction area between the active precursor and the ultrafine silicon powder; (2) adopting extrusion molding-calcination to prepare a high-strength carrier, using water solvent and ultrasonic cleaning to remove the pore-forming agent, form pores, and prepare a catalyst carrier with well-developed and uniformly distributed pores and good wear resistance, thereby reducing the escape of the catalyst and extending the service life of the catalyst; (3) compared with liquid and solid phase compounds, gas phase compounds have stronger diffusivity in the pores, strengthen the reaction with ultrafine silicon powder pieces, thereby increasing the active sites, and promoting the adsorption and reaction of silicon tetrachloride and hydrogen in the cold hydrogenation reaction process; (4) adopting a co-catalyst and a reducing atmosphere is beneficial to removing oxygen atoms on the surface of ultrafine silicon powder, realizing the valence state transformation of the main catalyst precursor, strengthening diffusion and electron transfer, and promoting the formation of active nano-active intermediates; (5) the induction period of the cold hydrogenation reaction can be shortened and the conversion rate of silicon tetrachloride can be improved.

[0113] The present embodiment relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst is mainly composed of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst is a porous catalyst. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size distribution, large number density of active components, high content of active components, and a large number of sites. In a fluidized bed reactor, it is beneficial to promote the adsorption-diffusion-reaction of hydrogen and silicon tetrachloride on the catalyst during the cold hydrogenation reaction, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of active components due to too small particle size, improving the utilization rate of active components, reducing unnecessary waste of active components, and reducing the cost of the catalyst.

[0114] Example 3

[0115] The catalyst in this embodiment is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The catalyst is prepared using the device in Example 2, and the difference between the preparation method and that in Example 2 is as follows:

[0116] In the first step, the catalyst carrier raw material composition is: 500g kaolin, 500g fly ash, 300g ultrafine silica powder, 120g pore-forming agent, and 300g adhesive. The particle size of the kaolin, fly ash, ultrafine silica powder and pore-forming agent is 325-600 mesh, the pore-forming agent is sodium chloride, and the adhesive is sodium stearate.

[0117] In the third step, the calcination temperature is 690°C.

[0118] In the sixth step, the amount of cupric chloride used is 400 g, the amount of zinc chloride used is 50 g, and the amount of aluminum chloride used is 50 g.

[0119] In the seventh step, the reducing gas is methanol.

[0120] The catalyst surface area is 95m 2 / g, the porosity is 21.4%, the equivalent particle size range is 0.32-0.98mm, the main catalyst metal element content is 19.4%, and the co-catalyst metal element content is 4.8%.

[0121] The catalyst prepared in this example was used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature was 500-550° C., the catalytic conversion efficiency of silicon tetrachloride was 31.9%, and the reaction was circulated for 144 hours.

[0122] The present embodiment relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst is mainly composed of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst is a porous catalyst. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size distribution, large number density of active components, high content of active components, and a large number of sites. In a fluidized bed reactor, it is beneficial to promote the adsorption-diffusion-reaction of hydrogen and silicon tetrachloride on the catalyst during the cold hydrogenation reaction, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of active components due to too small particle size, improving the utilization rate of active components, reducing unnecessary waste of active components, and reducing the cost of the catalyst.

[0123] Example 4

[0124] The catalyst in this embodiment is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The catalyst is prepared using the device in Example 2, and the difference between the preparation method and that in Example 2 is as follows:

[0125] In the first step, the catalyst carrier raw material composition is: 500g kaolin, 500g fly ash, 400g ultrafine silica powder, 135g pore-forming agent, and 300g adhesive. The particle size of the kaolin, fly ash, ultrafine silica powder and pore-forming agent is 325-600 mesh, the pore-forming agent is sodium chloride, and the adhesive is sodium stearate.

[0126] In the third step, the calcination temperature is 690°C.

[0127] In the sixth step, the amount of cupric chloride used is 350 g, the amount of zinc chloride used is 50 g, the amount of nickel chloride used is 50 g, and the amount of aluminum chloride used is 50 g.

[0128] In the seventh step, the reducing gas is formaldehyde.

[0129] The catalyst surface area is 108m 2 / g, the porosity is 24.1%, the equivalent particle size range is 0.32-0.98mm, the main catalyst metal element content is 24.1%, and the co-catalyst metal element content is 5.4%.

[0130] The catalyst prepared in this example was used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature was 500-550° C., the catalytic conversion efficiency of silicon tetrachloride was 35.7%, and the reaction was circulated for 144 hours.

[0131] The present embodiment relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst is mainly composed of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst is a porous catalyst. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size distribution, large number density of active components, high content of active components, and a large number of sites. In a fluidized bed reactor, it is beneficial to promote the adsorption-diffusion-reaction of hydrogen and silicon tetrachloride on the catalyst during the cold hydrogenation reaction, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of active components due to too small particle size, improving the utilization rate of active components, reducing unnecessary waste of active components, and reducing the cost of the catalyst.

[0132] Comparative Example 1

[0133] The catalyst in this comparative example is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The difference between this catalyst preparation method and that in Example 2 is:

[0134] In the first step, the catalyst carrier raw material composition is: 500g kaolin, 500g fly ash, 400g ultrafine silica powder, 135g pore-forming agent, and 300g adhesive. The particle size of the diatomaceous earth, fly ash, ultrafine silica powder and pore-forming agent is 325-600 mesh, the pore-forming agent is sodium chloride, and the adhesive is sodium stearate.

[0135] In the third step, the calcination temperature is 690°C.

[0136] In the sixth step, the amount of cupric chloride used is 500 g.

[0137] In the seventh step, the reducing gas is formaldehyde.

[0138] After testing, the specific surface area of ​​the catalyst is 103m2 / g, the porosity is 23.8%, the equivalent particle size range is 0.31-0.97, and the metal element content of the catalyst is 19.1%. Compared with multi-metal silicides, the density of defects such as solid solution atoms and phase interface grain boundaries in the binary silicon copper phase is significantly reduced. Compared with Example 3, the activity of the catalyst prepared in Comparative Example 1 decreases. The catalyst prepared in this comparative example is used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature is 500-550°C, the catalytic conversion efficiency of silicon tetrachloride is 26.9%. After 144 hours of recycling, the catalytic conversion rate does not change significantly.

[0139] Comparative Example 2

[0140] The catalyst in this comparative example is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The difference between this catalyst preparation method and that in Example 2 is:

[0141] In the first step, the catalyst carrier raw material composition is: 500g kaolin, 500g fly ash, 400g ultrafine silica powder, 135g pore-forming agent, and 300g adhesive. The particle size of the diatomaceous earth, fly ash, ultrafine silica powder and pore-forming agent is 325-600 mesh, the pore-forming agent is sodium chloride, and the adhesive is sodium stearate.

[0142] In the third step, the calcination temperature is 690°C.

[0143] In the sixth step, the amount of cupric chloride used is 350 g, the amount of zinc chloride used is 50 g, the amount of nickel chloride used is 50 g, and the amount of aluminum chloride used is 50 g.

[0144] In the seventh step, no reducing gas was used.

[0145] The catalyst surface area is 103m 2 / g, the porosity is 23.8%, the catalyst metal element content is 22.1%, and the XRD and XPS characterization results show that the main catalyst metal element is divalent copper (mainly cupric chloride), and active monovalent copper and silicon copper phase are not detected.

[0146] The catalyst prepared in this comparative example is used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature is 500-550°C, after the reaction for 25 minutes, the chlorosilane component is sampled and tested, and trichlorosilane is not detected, that is, within 25 minutes, the catalyst is inactive; sampling and analysis after 45 minutes, the conversion rate of silicon tetrachloride is 15.1%, and sampling and analysis after 90 minutes, the conversion rate of silicon tetrachloride is 32.1%; continued sampling and analysis, the conversion rate of silicon tetrachloride has not changed significantly. After 144 hours of recycling, the catalytic conversion rate has not changed significantly. That is, because no reducing agent is used, the metal elements in the prepared catalyst are mainly chlorides, the oxygen atoms on the surface of the fine silicon powder cannot be effectively removed, and the active intermediate of metal silicide cannot be formed. Therefore, in the cold hydrogenation reaction, there is an induction period, and the catalyst is inactive or has low activity at the initial stage of the reaction, and the conversion rate of silicon tetrachloride is low.

[0147] Comparative Example 3

[0148] The catalyst in this comparative example is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The difference between this catalyst preparation method and that in Example 2 is:

[0149] In the first step, the catalyst carrier raw material composition is: 500g kaolin, 500g fly ash, 400g ultrafine silicon powder and 300g adhesive. The particle size of kaolin, fly ash and ultrafine silicon powder is 500-1000 mesh, and the adhesive is sodium stearate.

[0150] In the third step, the calcination temperature is 690°C.

[0151] In the sixth step, the amount of cupric chloride used is 350 g, the amount of zinc chloride used is 50 g, the amount of nickel chloride used is 50 g, and the amount of aluminum chloride used is 50 g.

[0152] In the seventh step, the reducing gas is formaldehyde.

[0153] In the first step, no pore former was used.

[0154] Since no pore-forming agent is used in the catalyst preparation process, the specific surface area and porosity of the catalyst are significantly reduced compared with the catalyst prepared in Example 3, which inhibits the diffusion and deposition of gas phase chloride in the pores of the catalyst carrier, so the metal loading is low. According to the test, the specific surface area of ​​the catalyst is less than 20m2 / g, the porosity is 5.1%, the metal element content of the main catalyst is 6.1%, and the metal element content of the co-catalyst is 2.1%.

[0155] The catalyst prepared by this comparative example has low specific surface area, porosity and metal loading, which inhibits the adsorption and reaction of silicon tetrachloride and hydrogen on the inner and outer surfaces of the catalyst in a fixed bed reactor, so the conversion rate of silicon tetrachloride is low. When the hydrochlorination temperature is 500-550°C in a fixed bed reactor, the catalytic conversion efficiency of silicon tetrachloride is 16.4%, and the catalytic conversion rate does not change significantly after 144 hours of recycling.

[0156] Example 5

[0157] The catalyst in this embodiment is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The catalyst is prepared using the above-mentioned device, and the preparation method includes the following steps:

[0158] Step 1: Mixing: Mix the carrier raw material, silicon powder, pore former and adhesive according to a preset ratio, wherein the components in the mixture are as follows: the mass fraction of the carrier raw material is 80%, the mass fraction of silicon powder is 5%, the mass fraction of the adhesive is 10%, and the mass fraction of the pore former is 5%. The carrier raw material is fly ash; the silicon powder is the bag dust removal powder produced in the polysilicon reduction process, with a particle size of less than 100 mesh; the adhesive is polyvinyl alcohol; and the pore former is an alkali metal chloride. The mixing step is specifically ball milling in an inert atmosphere, the speed of the ball mill used for ball milling is 200r / min, and the ball milling time is 6h.

[0159] Step 2: Forming: The mixture is formed by extrusion method and dried; the drying temperature is 120°C.

[0160] The third step is calcination: the catalyst carrier prepared in the second step is calcined in a vacuum or nitrogen atmosphere; the calcination temperature is 600°C and the calcination time is 8 hours.

[0161] Step 4: Pore formation: The catalyst carrier prepared in the third step is cleaned in water solvent and ultrasonic conditions to remove the pore-forming agent, form pores, and dry to obtain a porous catalyst carrier with a well-developed pore structure for use.

[0162] Step 5: Add a porous catalyst carrier to the fixed bed reactor 2, open the second valve 4 and the third valve 7, and fully replace the fixed bed reactor with an inert gas, wherein the inert gas is nitrogen.

[0163] Step 6: Weigh copper chloride and add it to the first heater 10, weigh zinc chloride and add it to the second heater 11, turn on the first heater and the second heater, adjust the heating power of the first heater and the second heater to 40kw and 10kw respectively, heat and vaporize the catalyst precursor, turn on the inert gas storage tank 6, pass the carrier into the first heater and the second heater, and fully mix the main catalyst precursor and the co-catalyst precursor in the mixing tank 5; the mass proportion of the main catalyst precursor in the catalyst precursor is 70%, and the mass proportion of the co-catalyst precursor is 30%. The heating method of the first heater and the second heater is plasma heating, and the heating temperature is 700℃.

[0164] Step 7: Open the second valve 4 and the first valve 3. At the same time, keep the first heater and the second heater open and continue to introduce inert gas into them, so that the catalyst precursor vapor and the reducing vapor pass through the fixed bed reactor and fully contact with the porous catalyst carrier for adsorption reaction. The tail gas is circulated into the mixing tank. The adsorption reaction time is 8 hours. The reducing vapor is ethanol vapor.

[0165] Step 8: After the adsorption-reaction is completed, inert gas is used for cooling to obtain the catalyst for cold hydrogenation reaction, which is packaged for standby use.

[0166] According to the test, the catalyst particle size is 0.5-2.2mm, the length is 0.2-1.2mm, and the specific surface area is ≥60m 2 / g.

[0167] The catalyst prepared in this embodiment is used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature is 500-550° C., the catalytic conversion efficiency of silicon tetrachloride is 29.8%, and the cyclic use is 144 hours.

[0168] The present embodiment relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst is mainly composed of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst is a porous catalyst. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size distribution, large number density of active components, high content of active components, and a large number of sites. In a fluidized bed reactor, it is beneficial to promote the adsorption-diffusion-reaction of hydrogen and silicon tetrachloride on the catalyst during the cold hydrogenation reaction, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of active components due to too small particle size, improving the utilization rate of active components, reducing unnecessary waste of active components, and reducing the cost of the catalyst.

[0169] Example 6

[0170] The catalyst in this embodiment is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The catalyst is prepared using the above-mentioned device, and the preparation method includes the following steps:

[0171] Step 1: Mixing: Mix the carrier raw material, silicon powder, pore former and adhesive according to a preset ratio, wherein the components in the mixture are as follows: the mass fraction of the carrier raw material is 62%, the mass fraction of silicon powder is 15%, the mass fraction of the adhesive is 15%, and the mass fraction of the pore former is 8%. The carrier raw material is clay mineral; the silicon powder is bag dust removal powder produced by the cold hydrogenation process, with a particle size of less than 100 mesh; the adhesive is stearic acid and stearate; the pore former is alkaline earth metal chloride. The mixing step is specifically ball milling in an inert atmosphere, the speed of the ball mill used for ball milling is 400r / min, and the ball milling time is 2h.

[0172] Step 2: Forming: The mixture is formed by extrusion method and dried; the drying temperature is 60°C.

[0173] The third step is calcination: the catalyst carrier prepared in the second step is calcined under vacuum or nitrogen atmosphere; the calcination temperature is 750°C and the calcination time is 2h.

[0174] Step 4: Pore formation: The catalyst carrier prepared in the third step is cleaned in water solvent and ultrasonic conditions to remove the pore-forming agent, form pores, and dry to obtain a porous catalyst carrier with a well-developed pore structure for use.

[0175] Step 5: Add a porous catalyst carrier to the fixed bed reactor 2, open the second valve 4 and the third valve 7, and fully replace the fixed bed reactor with an inert gas, wherein the inert gas is argon.

[0176] Step 6: Weigh copper chloride and add it to the first heater 10, weigh zinc chloride and aluminum chloride and add them to the second heater 11, turn on the first heater and the second heater, adjust the heating power of the first heater and the second heater to 20kw and 20kw respectively, heat and vaporize the catalyst precursor, turn on the inert gas storage tank 6, pass the carrier into the first heater and the second heater, and fully mix the main catalyst precursor and the co-catalyst precursor in the mixing tank 5; the mass proportion of the main catalyst precursor in the catalyst precursor is 90%, and the mass proportion of the co-catalyst precursor is 10%. The heating method of the first heater and the second heater is microwave heating, and the heating temperature is 1000℃.

[0177] Step 7: Open the second valve 4 and the first valve 3, and at the same time, keep the first heater and the second heater open, and continue to introduce inert gas therein, so that the catalyst precursor steam and the reducing steam pass through the fixed bed reactor, fully contact with the porous catalyst carrier, and undergo adsorption reaction. The tail gas is circulated into the mixing tank. The adsorption reaction time is 8 hours, and the reducing steam is methane steam.

[0178] Step 8: After the adsorption-reaction is completed, inert gas is used for cooling to obtain the catalyst for cold hydrogenation reaction, which is packaged for standby use.

[0179] According to the test, the catalyst particle size is 0.5-2.2mm, the length is 0.2-1.2mm, and the specific surface area is ≥60m 2 / g.

[0180] The catalyst prepared in this embodiment is used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature is 500-550° C., the catalytic conversion efficiency of silicon tetrachloride is 29.8%, and the cyclic use is 144 hours.

[0181] The present embodiment relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst is mainly composed of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst is a porous catalyst. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size distribution, large number density of active components, high content of active components, and a large number of sites. In a fluidized bed reactor, it is beneficial to promote the adsorption-diffusion-reaction of hydrogen and silicon tetrachloride on the catalyst during the cold hydrogenation reaction, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of active components due to too small particle size, improving the utilization rate of active components, reducing unnecessary waste of active components, and reducing the cost of the catalyst.

[0182] Example 7

[0183] The catalyst in this embodiment is a porous columnar material composed of a carrier, a main catalyst and a co-catalyst. The catalyst is prepared using the above-mentioned device, and the preparation method includes the following steps:

[0184] Step 1: Mixing: Mix the carrier raw material, silicon powder, pore former and adhesive according to a preset ratio, wherein the components in the mixture are as follows: the mass fraction of the carrier raw material is 45%, the mass fraction of silicon powder is 25%, the mass fraction of the adhesive is 20%, and the mass fraction of the pore former is 10%. The carrier raw materials are clay minerals and fly ash; the silicon powder is the bag dust removal powder produced in the polysilicon reduction process, with a particle size of less than 100 mesh; the adhesive is stearate; the pore former is alkali metal chloride and alkaline earth metal chloride. The mixing step is specifically ball milling mixing under an inert atmosphere, the speed of the ball mill used for ball milling is 300r / min, and the ball milling time is 12h.

[0185] Step 2: Forming: The mixture is formed by extrusion method and dried; the drying temperature is 150°C.

[0186] The third step is calcination: the catalyst carrier prepared in the second step is calcined in a vacuum or nitrogen atmosphere; the calcination temperature is 700°C and the calcination time is 12 hours.

[0187] Step 4: Pore formation: The catalyst carrier prepared in the third step is cleaned in water solvent and ultrasonic conditions to remove the pore-forming agent, form pores, and dry to obtain a porous catalyst carrier with a well-developed pore structure for use.

[0188] Step 5: Add a porous catalyst carrier to the fixed bed reactor 2, open the second valve 4 and the third valve 7, and fully replace the fixed bed reactor with an inert gas, wherein the inert gas is nitrogen.

[0189] Step 6: Weigh copper chloride and add it to the first heater 10, weigh nickel chloride and aluminum chloride and add them to the second heater 11, turn on the first heater and the second heater, adjust the heating power of the first heater and the second heater to 10kw and 40kw respectively, heat and vaporize the catalyst precursor, turn on the inert gas storage tank 6, pass the carrier into the first heater and the second heater, and fully mix the main catalyst precursor and the co-catalyst precursor in the mixing tank 5; the mass proportion of the main catalyst precursor in the catalyst precursor is 85%, and the mass proportion of the co-catalyst precursor is 15%. The heating method of the first heater and the second heater is heat conduction heating, and the heating temperature is 500℃.

[0190] Step 7: Open the second valve 4 and the first valve 3. At the same time, keep the first heater and the second heater open and continue to introduce inert gas into them, so that the catalyst precursor vapor and the reducing vapor pass through the fixed bed reactor, fully contact with the porous catalyst carrier, and undergo adsorption reaction. The tail gas is circulated into the mixing tank. The adsorption reaction time is 8 hours. The reducing vapor is formaldehyde vapor. Of course, the reducing vapor can also be any one of ethane, methanol, ether, dimethyl ether, and acetone.

[0191] Step 8: After the adsorption-reaction is completed, inert gas is used for cooling to obtain the catalyst for cold hydrogenation reaction, which is packaged for standby use.

[0192] According to the test, the catalyst particle size is 0.5-2.2mm, the length is 0.2-1.2mm, and the specific surface area is ≥60m 2 / g.

[0193] The catalyst prepared in this embodiment is used to carry out hydrochlorination reaction in a fixed bed reactor. When the hydrochlorination temperature is 500-550° C., the catalytic conversion efficiency of silicon tetrachloride is 29.8%, and the cyclic use is 144 hours.

[0194] The present embodiment relates to a catalyst for cold hydrogenation reaction and a preparation method thereof. The catalyst is mainly composed of a carrier and a catalyst active component. The active component is a multi-metal silicide formed by in-situ gas phase loading-reaction. The catalyst is a porous catalyst. The catalyst has the characteristics of large specific surface area, wear resistance, moderate particle size distribution, large number density of active components, high content of active components, and a large number of sites. In a fluidized bed reactor, it is beneficial to promote the adsorption-diffusion-reaction of hydrogen and silicon tetrachloride on the catalyst during the cold hydrogenation reaction, thereby improving the conversion rate of silicon tetrachloride, inhibiting the escape of active components due to too small particle size, improving the utilization rate of active components, reducing unnecessary waste of active components, and reducing the cost of the catalyst.

[0195] It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for preparing a catalyst for cold hydrogenation reaction, characterized in that: The following steps are involved: 1) In a non-oxidizing atmosphere, a catalyst precursor is heated to a gas phase, and the gas phase is mixed with a porous catalyst carrier, wherein the catalyst precursor comprises: a main catalyst precursor, and the main catalyst precursor is cupric chloride; 2) The gas phase diffuses into the porous catalyst carrier and is adsorbed. After the adsorption is completed, it is cooled to obtain a catalyst for the cold hydrogenation reaction.

2. The method for preparing a catalyst for cold hydrogenation reaction according to claim 1, characterized in that: The catalyst precursor also includes: a promoter precursor, which is at least one of zinc chloride, nickel chloride and aluminum chloride.

3. The method for preparing a catalyst for cold hydrogenation reaction according to claim 2, characterized in that: The mass proportion of the main catalyst precursor in the catalyst precursor is 70-90%, and the mass proportion of the co-catalyst precursor is 10-30%.

4. The method for preparing a catalyst for cold hydrogenation reaction according to claim 2, characterized in that: In the catalyst for cold hydrogenation reaction, the mass content of metal elements in the main catalyst is 15-25%, and the mass content of metal elements in the co-catalyst is 5-15%.

5. The method for preparing a catalyst for cold hydrogenation reaction according to claim 1, characterized in that: The catalyst particle size is 0.5-2.2 mm, the length is 0.2-1.2 mm, and the specific surface area is ≥60m 2 / g.

6. The method for preparing a catalyst for cold hydrogenation reaction according to any one of claims 1 to 5, characterized in that: The heating method of step 1) is any one of plasma heating, microwave heating, thermal conduction heating and radiation heating.

7. The method for preparing a catalyst for cold hydrogenation reaction according to claim 6, characterized in that: The heating method of step 1) is plasma heating, and the power of plasma heating is 10-40kw.

8. The method for preparing a catalyst for cold hydrogenation reaction according to any one of claims 1 to 5, characterized in that: The heating temperature in step 1) is 500-1000°C.

9. The method for preparing a catalyst for cold hydrogenation reaction according to any one of claims 1 to 5, characterized in that: The step 2) is carried out under a reducing atmosphere.

10. The method for preparing a catalyst for cold hydrogenation reaction according to claim 9, characterized in that: The reducing steam used in the reducing atmosphere is a small molecule organic substance, and the small molecule organic substance is any one of methane, ethane, methanol, ethanol, ether, dimethyl ether, formaldehyde, and acetone.

11. The method for preparing a catalyst for cold hydrogenation reaction according to claim 1, characterized in that: The method further comprises the following steps: preparation of a porous catalyst carrier, specifically: The first step is mixing: mixing the carrier raw material, silicon powder, pore-forming agent and adhesive according to a preset ratio; Step 2: Forming: Use the extrusion method to form the mixture and dry it; Step 3: calcining: calcining the catalyst carrier prepared in step 2 under vacuum or nitrogen atmosphere; Step 4: Pore formation: The catalyst carrier prepared in the third step is cleaned in water solvent and ultrasonic conditions to remove the pore-forming agent, form pores, and dry to obtain a porous catalyst carrier with a well-developed pore structure for use.

12. The method for preparing a catalyst for cold hydrogenation reaction according to claim 11, characterized in that: In the first step, the components in the mixture are as follows: the mass fraction of the carrier raw material is 45-80%, the mass fraction of the silicon powder is 5-25%, the mass fraction of the adhesive is 10-20%, and the mass fraction of the pore former is 5-10%.

13. The method for preparing a catalyst for cold hydrogenation reaction according to claim 11, characterized in that: The carrier raw material is clay mineral and / or fly ash; Silicon powder is bag dust removal powder produced in the polysilicon reduction process or cold hydrogenation process, and its particle size is less than 100 mesh; The adhesive is polyvinyl alcohol, stearic acid, stearate or a mixture of two thereof; The pore former is one or a mixture of alkali metal chlorides and / or alkaline earth metal chlorides.

14. The method for preparing a catalyst for cold hydrogenation reaction according to any one of claims 11 to 13, characterized in that: In the first step, the mixing step is specifically ball milling mixing under an inert atmosphere, the rotation speed of the ball mill used for ball milling is 200 to 400 r / min, and the ball milling time is 2 to 12 hours; In the second step, the drying temperature is 60-150°C; In the third step, the calcination temperature is 600-750° C. and the calcination time is 2-12 hours.

15. A catalyst for cold hydrogenation reaction, characterized in that: The compound is obtained by the preparation method according to any one of claims 1 to 14.

Images