Transition metal sulfide catalyst and application thereof

Abstract

The invention discloses a transition metal sulfide catalyst and application thereof. The transition metal sulfide catalyst is prepared according to the following steps: dissolving a molybdenum source and a sulfur source in water to obtain a first mixed solution; adding silica sol and / or orthosilicate into the first mixed solution, and fully stirring to obtain a second mixed solution; drying, grinding and roasting the second mixed solution to obtain a precursor; and etching and drying the precursor to obtain the molybdenum sulfide catalyst. The catalyst prepared in the invention is a nano-scale sulfide, has abundant Mo cation sites and a unique near defect structure, and improves the stability of active species and the capability of catalyzing carbon dioxide hydrogenation to prepare carbon monoxide.

Description

Technical Field

[0001] The present invention relates to a transition metal sulfide catalytic material and its application. Background Art

[0002] The catalytic conversion of CO2 is a multi-faceted endeavor, depending on various influencing factors, including the availability of renewable energy and low-carbon intensity hydrogen. In this context, the production of CO via the reverse water-gas shift (RWGS) reaction is gaining attention because the resulting CO or syngas (CO + H2) can be used as building blocks to produce various chemicals in catalytic systems. Most syngas conversion reactions are well-established commercial technologies, highlighting the great value of CO and syngas. Economic studies have shown that the CO2 utilization route mediated by carbon monoxide can provide a competitive advantage over other alternatives, especially in cases where renewable energy is readily available. To realize the full potential of the RWGS reaction globally, the catalysts used must meet important criteria. First, the techno-economic assessment of the RWGS reaction indicates that the process can only be overall carbon-negative if the catalyst is 100% CO-selective, such that no hydrogen is wasted in the production of harmful methane, which also simplifies downstream separation methods. Using thermal catalytic reduction techniques to reduce carbon dioxide to carbon monoxide is one of the main measures for recycling carbon dioxide waste resources. Improving the high-temperature carbon monoxide production rate through rational catalyst design is a good strategy for enhancing catalytic performance, but the preparation method of a selectively catalytic CO2 hydrogenation catalyst with high CO synthesis activity still needs further exploration. Summary of the Invention

[0003] In view of the above-mentioned defects of the prior art, on the one hand, the present application provides a transition metal sulfide catalyst, which is prepared as follows:

[0004] Dissolve a molybdenum source and a sulfur source in water to obtain a first mixed solution;

[0005] Add silica sol and / or tetraethyl orthosilicate to the first mixed solution and stir well to obtain a second mixed solution;

[0006] Dry, grind, and calcine the second mixed solution to obtain a precursor;

[0007] The precursor is etched and dried to obtain a molybdenum sulfide catalyst. The catalyst prepared in this application is a nanoscale sulfide, which has abundant Mo cation sites and a unique adjacent defect structure (such as sulfur vacancies and oxygen vacancies), increasing the stability of active species and the ability to catalyze the hydrogenation of carbon dioxide to produce carbon monoxide; the prepared alkali-modified molybdenum sulfide catalyst promotes the improvement of the carbon dioxide adsorption and conversion rates. The combination of these two advantages is conducive to the high-activity catalytic reduction of carbon dioxide to produce carbon monoxide; at the same time, it also gives the catalyst a long service life and can catalytically reduce carbon dioxide to synthesize carbon monoxide with high activity and high selectivity.

[0008] Preferably, it further includes the process of loading the molybdenum sulfide catalyst, including the following steps:

[0009] Put the molybdenum sulfide catalyst into water with a mass 10 times that of the catalyst, and then add a water-soluble alkali metal salt and / or alkaline earth metal salt to obtain a third mixed solution;

[0010] Stir, dry, grind, and calcine the third mixed solution to obtain a loaded catalyst.

[0011] Preferably, the molybdenum sulfide catalyst is granulated, and the particle size is 20 - 40 mesh.

[0012] Preferably, the loaded catalyst is granulated, and the particle size is 20 - 40 mesh.

[0013] Preferably, the molar ratio of the metal element of the alkali metal salt and / or alkaline earth metal salt to the metal element of the molybdenum sulfide catalyst is 1:30 - 50;

[0014] The alkali metal salt is one or a mixture of any proportion of two or more of lithium sulfate, lithium nitrate, lithium carbonate, lithium chloride, lithium acetate, lithium acetate dihydrate, or, one or a mixture of any proportion of two or more of sodium sulfate, sodium nitrate, sodium carbonate, sodium chloride, sodium acetate, or, one or a mixture of any proportion of two or more of potassium sulfate, potassium carbonate, potassium hydroxide, potassium chloride, potassium acetate, potassium phosphate trihydrate, or, one or a mixture of any proportion of two or more of cesium sulfate, cesium nitrate, cesium carbonate, cesium hydroxide, cesium chloride;

[0015] The alkaline earth metal is one or a mixture of any proportion of two or more of beryllium nitrate, beryllium carbonate, beryllium chloride, or, one or a mixture of any proportion of two or more of magnesium sulfate, magnesium nitrate, magnesium chloride, or, one or a mixture of any proportion of two or more of calcium nitrate, calcium dihydrogen phosphate, calcium chlorate, calcium hypochlorite, calcium perchlorate, or, one or a mixture of any proportion of two of strontium nitrate, strontium chloride, or, one or a mixture of any proportion of two of barium nitrate, barium chloride.

[0016] Preferably, the molybdenum source is ammonium molybdate tetrahydrate, the sulfur source is thiourea, and the molar ratio of molybdenum to sulfur in the molybdenum source and the sulfur source is 1:2-3;

[0017] The second mixed solution is prepared as follows:

[0018] Add silica sol and / or tetraethyl orthosilicate to the first mixed solution, and stir well for 1.5-2 h to obtain the second mixed solution;

[0019] The tetraethyl orthosilicate is methyl orthosilicate or ethyl orthosilicate.

[0020] Preferably, the drying, grinding, and calcination of the second mixed solution are carried out as follows:

[0021] Perform rotary evaporation on the second mixed solution, control the temperature at 40-60 °C, and the duration is 2-2.5 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at a temperature of 70-80 °C and a vacuum of 1.5-2×10 4 Pa for drying. The dried product is the precursor of the catalyst;

[0022] Grind the sample after drying into a powder. In a tubular furnace, perform sulfidation treatment with a hydrogen-argon mixed gas. The temperature of the tubular furnace is 300-350 °C, and the reaction time is 3-4 h. Then collect the precursor.

[0023] Preferably, the etching and drying of the precursor are carried out according to the following steps:

[0024] Put the precursor into a 20-25 wt% sodium hydroxide solution with a mass 3-4 times that of the precursor at 20-30 °C for 4-5 h, and maintain stirring during the process; after the treatment, perform centrifugation and dry it in a vacuum drying oven at a temperature of 70-80 °C and a vacuum of 1.5-2×10 4 Pa, and perform grinding operation. The finally collected powder solid is the molybdenum sulfide catalyst.

[0025] Preferably, the third mixed solution is prepared as follows:

[0026] Put the molybdenum sulfide catalyst into water with a mass 8-10 times that of the catalyst, then add an alkali metal salt and / or an alkaline earth metal salt, and then stir. The stirring temperature is 10-40 °C, and the time is 0.5-1 h;

[0027] Dry the stirred solution as follows:

[0028] Perform rotary evaporation treatment, the temperature is 40-60 °C, and the time is 1.5-2 h;

[0029] Then it is ground into a powder and placed in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The temperature of the tube furnace is 250-300 °C, the reaction time is 2-3 h. After the reaction is completed, the tube furnace is allowed to cool naturally to room temperature, and the obtained black solid powder is collected. This powder is the supported catalyst. The high-performance sulfide catalyst material provided by this application has the advantage of significantly improving the selectivity of CO; the raw materials used in its preparation method are simple and easy to obtain, and at the same time the process is simple, convenient and safe, and the products prepared have good repeatability; the surface of the prepared sulfide material is rich in sulfur vacancies and metal-O-metal interface species, which increases the stability of the active species, the catalytic dissociation hydrogen activity and the ability to activate carbon dioxide; it is beneficial to the high-activity catalytic reduction reaction of carbon dioxide. In addition, the catalytic material produced by this preparation method has a long service life and can catalytically reduce carbon dioxide to synthesize carbon monoxide with high activity and high selectivity.

[0030] On the other hand, this application also discloses the application of transition metal sulfide catalysts in the preparation of carbon monoxide from carbon dioxide. The high-performance transition metal sulfide catalyst material provided by this application has the advantage of significantly improving the selectivity of carbon monoxide in the product; the raw materials used in its preparation method are simple and easy to obtain, and at the same time the process is simple, convenient and safe, and the products prepared have good repeatability.

[0031] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0032] 1. The high-performance sulfide catalyst material provided by this application has the advantage of significantly improving the selectivity of CO; the raw materials used in its preparation method are simple and easy to obtain, and at the same time the process is simple, convenient and safe, and the products prepared have good repeatability; the surface of the prepared sulfide material is rich in sulfur vacancies and metal-O-metal interface species, which increases the stability of the active species, the catalytic dissociation hydrogen activity and the ability to activate carbon dioxide; it is beneficial to the high-activity catalytic reduction reaction of carbon dioxide. In addition, the catalytic material produced by this preparation method has a long service life and can catalytically reduce carbon dioxide to synthesize carbon monoxide with high activity and high selectivity.

[0033] 2. The highly catalytically active sulfide catalytic material provided by the present invention is suitable for the selective catalytic hydrogenation of carbon dioxide to prepare carbon monoxide. The carbon dioxide can be sourced from industrial tail gas carbon dioxide mixtures, and the hydrogen can be sourced from renewable energy - electrolytic water to produce green hydrogen and / or gray hydrogen in coal chemical and petrochemical industries, which can relieve the pressure of carbon dioxide emissions, while producing high-value-added chemicals and generating economic benefits. Specific Embodiments

[0034] The present invention will be further illustrated below by way of examples, but the present invention is not limited to the scope of the examples described herein. The experimental methods not specified in the following examples are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0035] This application discloses a transition metal sulfide catalyst, which is prepared as follows:

[0036] S1. Dissolve a molybdenum source and a sulfur source in water to obtain a first mixed solution;

[0037] The molybdenum source is ammonium molybdate tetrahydrate, and the sulfur source is thiourea. The molar ratio of molybdenum to sulfur in the molybdenum source and the sulfur source is 1:2 - 3;

[0038] S2. Add silica sol and / or tetraethyl orthosilicate to the first mixed solution and stir well to obtain a second mixed solution;

[0039] The second mixed solution is prepared as follows:

[0040] Add silica sol and / or tetraethyl orthosilicate to the first mixed solution and stir well for 1.5 - 2 h to obtain a second mixed solution;

[0041] The tetraethyl orthosilicate is methyl orthosilicate or ethyl orthosilicate.

[0042] S3. Dry, grind, and calcine the second mixed solution to obtain a precursor;

[0043] The drying, grinding, and calcining of the second mixed solution are carried out as follows:

[0044] Perform rotary evaporation on the second mixed solution, control the temperature at 40 - 60 °C, and the duration at 2 - 2.5 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at a temperature of 70 - 80 °C and a vacuum degree of 1.5 - 2×10 4 Pa for drying treatment. The dried product is the precursor of the catalyst;

[0045] Grind the sample after drying treatment into powder form, and carry out sulfidation treatment with a hydrogen - argon mixed gas in a tubular furnace. The temperature of the tubular furnace is 300 - 350 °C, and the reaction time is 3 - 4 h. Then collect the precursor.

[0046] S4. Etch and dry the precursor to obtain a molybdenum sulfide catalyst.

[0047] The etching and drying of the precursor are carried out according to the following steps:

[0048] Put the precursor into a 20 - 25 wt% sodium hydroxide solution with a mass 3 - 4 times that of the precursor at 20 - 30 °C for 4 - 5 h, and maintain stirring during the process; after the treatment is completed, carry out centrifugation, and dry it in a vacuum drying oven at a temperature of 70 - 80 °C and a vacuum degree of 1.5 - 2×10 4 Pa, and perform grinding operation. The finally collected powder solid is the molybdenum sulfide catalyst.

[0049] The molybdenum sulfide catalyst is granulated, and the particle size is 20 - 40 mesh.

[0050] S5. It also includes the process of loading the molybdenum sulfide catalyst, which includes the following steps:

[0051] Put the molybdenum sulfide catalyst into water with a mass 8 - 10 times that of the catalyst, and then add water-soluble alkali metal salts and / or alkaline earth metal salts to obtain a third mixed solution;

[0052] Stir, dry, grind, and calcine the third mixed solution to obtain a loaded catalyst.

[0053] Specifically, the third mixed solution is prepared as follows:

[0054] Put the molybdenum sulfide catalyst into water with a mass 8 - 10 times that of the catalyst, then add alkali metal salts and / or alkaline earth metal salts, and then stir. The stirring temperature is 10 - 40 °C, and the time is 0.5 - 1 h;

[0055] Dry the stirred solution in the following way:

[0056] Perform rotary evaporation at a temperature of 40 - 60 °C for 1.5 - 2 h;

[0057] Then grind it into a powder, place it in a hydrogen - argon atmosphere in a tubular furnace for reduction treatment. The temperature of the tubular furnace is 250 - 300 °C, the reaction time is 2 - 3 h. After the reaction, wait for the tubular furnace to cool naturally to room temperature, and then collect the obtained black solid powder, which is the loaded catalyst.

[0058] The loaded catalyst is granulated, and the particle size is 20 - 40 mesh.

[0059] The molar ratio of the metal element of the alkali metal salt and / or alkaline earth metal salt to the metal element of the molybdenum sulfide catalyst is 1:30 - 50;

[0060] The alkali metal salt is one or a mixture of any proportion of two or more of lithium sulfate, lithium nitrate, lithium carbonate, lithium chloride, lithium acetate, lithium acetate dihydrate, or, one or a mixture of any proportion of two or more of sodium sulfate, sodium nitrate, sodium carbonate, sodium chloride, sodium acetate, or, one or a mixture of any proportion of two or more of potassium sulfate, potassium carbonate, potassium hydroxide, potassium chloride, potassium acetate, potassium phosphate trihydrate, or, one or a mixture of any proportion of two or more of cesium sulfate, cesium nitrate, cesium carbonate, cesium hydroxide, cesium chloride;

[0061] The alkaline earth metal is one or a mixture of two or more of beryllium nitrate, beryllium carbonate, and beryllium chloride in any proportion, or is one or a mixture of two or more of magnesium sulfate, magnesium nitrate, and magnesium chloride in any proportion, or is one or a mixture of two or more of calcium nitrate, calcium dihydrogen phosphate, calcium chlorate, calcium hypochlorite, and calcium perchlorate in any proportion, or is one or a mixture of two of strontium nitrate and strontium chloride in any proportion, or is one or a mixture of two of barium nitrate and barium chloride in any proportion.

[0062] The transition metal sulfide catalytic materials prepared in some examples were respectively used for the catalytic performance test experiment of CO2 gas to produce carbon monoxide. Among them, a micro fixed-bed simulation reaction system was established with the flow rate of the CO2 / H2 / N2 mixed gas (by volume percentage, containing 4% N2, 24% CO2, and 72% H2) being 36.0 mL / min and the pressure being 0.1 MPa. First, before the catalytic activity test, 0.015 g of the catalytic material sample was reduced in pure H2 or a hydrogen-argon gas stream at 600 °C and normal pressure for 1 h, and then the CO2 / H2 / N2 mixed reactants were introduced, and the catalytic performance was evaluated under normal pressure. The components of the obtained tail gas such as CO, CO2, and N2 were analyzed online quantitatively by a gas chromatograph equipped with a thermal conductivity detector and a flame ionization detector.

[0063] Example 1

[0064] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.2 g of silica sol was added and stirred at 25 °C for 2 h to obtain a second mixed solution;

[0065] The second mixed solution was rotary evaporated at 60 °C for 2 h. The product obtained by rotary evaporation was transferred to a vacuum drying oven at a temperature of 80 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, it was pulverized and calcined in a tubular furnace with a 10H%2 / Ar mixed gas (by volume fraction, the same below) at 350 °C for 3 h to obtain a powdery oxide material;

[0066] 1.7 g of the powdery oxide material, 5.6 g of a 25 wt% sodium hydroxide solution, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, centrifugation was carried out 5 times and dried in a vacuum drying oven at 80 °C and a vacuum degree of 2×10 4 Pa. After drying, a grinding operation was carried out, and the finally collected powdery solid was the molybdenum sulfide catalyst.

[0067] 0.015 g of the sulfide was tableted and granulated to 20 - 40 mesh to obtain a catalytic material, denoted as catalyst 1#.

[0068] Example 2

[0069] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 1.5 h to obtain a second mixed solution;

[0070] The second mixed solution is rotary evaporated at 40 °C for 2.5 h. The product obtained by rotary evaporation is transferred to a vacuum drying oven at a temperature of 70 °C and a vacuum degree of 1.5×10 4 Pa for drying treatment. After drying, it is pulverized and calcined in a tube furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0071] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 20 °C for 5 h. After the treatment is completed, perform 5 centrifugations, and dry in a vacuum drying oven at 70 °C with a vacuum degree of 1.5×10 4 Pa. After drying, perform a grinding operation. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0072] Dissolve 500 mg of MoS2 catalytic material and 2.5640 mg of Li2CO3 in 5 mL of deionized water, stir for 30 min, the stirring rate is 600 r / min, and the stirring temperature is 10 °C to obtain a third mixed solution;

[0073] Perform rotary evaporation on the third mixed solution at a temperature of 40 °C for 2 h. After the water is completely removed, grind the sample in an agate mortar to a powdery state, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the tube furnace temperature is 300 °C, the reaction is 2 h. After the reaction ends, wait for the tube furnace to cool naturally to room temperature and collect the obtained black solid powder, which is Li-MoS2.

[0074] Press 0.015 g of Li-MoS2 catalytic material into pellets with a particle size of 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 2#.

[0075] Example 3

[0076] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 20.0 g of methyl orthosilicate and stir at 25 °C for 2 h to obtain a second mixed solution;

[0077] The second mixed solution is rotary evaporated at 60 °C for 2 h, and the product obtained by rotary evaporation is transferred to a vacuum drying oven at a temperature of 80 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, it is crushed, and calcined in a tubular furnace with 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0078] 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water are mixed and stirred at 30 °C for 4 h. After the treatment is completed, it is centrifuged 5 times and dried in a vacuum drying oven at 80 °C and a vacuum degree of 2×10 4 Pa. After drying, it is ground, and the finally collected powdery solid is the molybdenum sulfide catalyst.

[0079] 500 mg of MoS2 catalytic material and 4.7959 mg of K2CO3 are dissolved in 5 mL of deionized water, stirred for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0080] The third mixed solution is rotary evaporated at a temperature of 60 °C for 1.5 h. After the water is completely removed, the sample is ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample is placed in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The content of hydrogen is 10% H2 / Ar, the temperature of the tubular furnace is 300 °C, the reaction is for 2 h. After the reaction ends, wait for the tubular furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is K-MoS2.

[0081] 0.015 g of K-MoS2 catalytic material is pressed and granulated into 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 3#.

[0082] Example 4

[0083] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea are dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.4 g of tetraethyl orthosilicate is added and stirred at 25 °C for 1.5 h to obtain a second mixed solution;

[0084] The second mixed solution is rotary evaporated at 40 °C for 2 h, and the product obtained by rotary evaporation is transferred to a vacuum drying oven at a temperature of 70 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, it is crushed, and calcined in a tubular furnace with 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0085] Mix 1.7 g of powdered oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 20 °C for 5 h. After the treatment, perform centrifugation 5 times, and dry in a vacuum drying oven at 70 °C with a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdered solid is the molybdenum sulfide catalyst.

[0086] Dissolve 500 mg of MoS2 catalytic material and 11.3060 mg of Cs2CO3 in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 10 °C to obtain a third mixed solution;

[0087] Perform rotary evaporation on the third mixed solution at a temperature of 40 °C for 1.5 h. After the water is completely removed, grind the sample in an agate mortar to a powder, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the tube furnace temperature is 300 °C, and the reaction is for 2 h. After the reaction, wait for the tube furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Cs-MoS2.

[0088] Press 0.015 g of Cs-MoS2 catalytic material into pellets with a particle size of 20 - 40 mesh to obtain an alkali metal salt-doped molybdenum sulfide catalytic material, denoted as catalyst 4#.

[0089] Example 5

[0090] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 1.5 h to obtain a second mixed solution;

[0091] Perform rotary evaporation on the second mixed solution at 40 °C for 2.5 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying treatment. After drying, crush it and calcine it in a tube furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain the powdered oxide material;

[0092] Mix 1.7 g of powdered oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 30 °C for 4 h. After the treatment, perform centrifugation 5 times, and dry in a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdered solid is the molybdenum sulfide catalyst.

[0093] Dissolve 500 mg of MoS2 catalytic material and 3.8149 mg of Li2SO4 in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 10 °C to obtain a third mixed solution;

[0094] Perform rotary evaporation on the third mixed solution at a temperature of 40 °C for 2 h. After the water is completely removed, grind the sample in an agate mortar to a powder, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the tube furnace temperature is 300 °C, the reaction is for 2 h. After the reaction ends, wait for the tube furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Li-MoS2.

[0095] Press 0.015 g of Li-MoS2 catalytic material into pellets of 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 5#.

[0096] Example 6

[0097] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 20.0 g of methyl orthosilicate and stir at 25 °C for 2 h to obtain a second mixed solution;

[0098] Perform rotary evaporation on the second mixed solution at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at a temperature of 80 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, pulverize it and calcine it in a tube furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0099] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, stir at 30 °C for 4 h. After the treatment is completed, perform centrifugation 5 times and dry it in a vacuum drying oven at 80 °C and a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation, and finally collect the obtained powdery solid, which is the molybdenum sulfide catalyst.

[0100] Dissolve 500 mg of MoS2 catalytic material and 7.7035 mg of MgSO4 in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0101] The third mixed solution was subjected to rotary evaporation at a temperature of 60 °C for 1.5 h. After the water was completely removed, the sample was ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content was 10% H2 / Ar, the tube furnace temperature was 300 °C, and the reaction was carried out for 2 h. After the reaction ended, the tube furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was Mg-MoS2.

[0102] 0.015 g of the Mg-MoS2 catalytic material was pressed and granulated to 20 - 40 mesh to obtain a molybdenum sulfide catalytic material doped with alkaline earth metal salts, denoted as catalyst 6#.

[0103] Example 7

[0104] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.2 g of silica sol was added and stirred at 25 °C for 2 h to obtain a second mixed solution;

[0105] The second mixed solution was subjected to rotary evaporation at 60 °C for 2 h. The product obtained by rotary evaporation was transferred to a vacuum drying oven at a temperature of 80 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, it was pulverized and calcined in a tube furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0106] 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, centrifugation was carried out 5 times and dried in a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa. After drying, grinding operation was carried out, and the finally collected powdery solid was the molybdenum sulfide catalyst.

[0107] 500 mg of the MoS2 catalytic material and 7.7035 mg 6.0468 mg of K2SO4 were dissolved in 5 mL of deionized water, stirred for 30 min, the stirring rate was 600 r / min, and the stirring temperature was 10 °C to obtain a third mixed solution;

[0108] The third mixed solution was subjected to rotary evaporation at a temperature of 60 °C for 1.5 h. After the water was completely removed, the sample was ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content was 10% H2 / Ar, the tube furnace temperature was 300 °C, and the reaction was carried out for 2 h. After the reaction ended, the tube furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was K-MoS2.

[0109] 0.015 g of the K-MoS₂ catalytic material was pelletized into 20 - 40 mesh particles to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as Catalyst 7#.

[0110] Example 8

[0111] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.4 g of tetraethyl orthosilicate was added and stirred at 25 °C for 2 h to obtain a second mixed solution;

[0112] The second mixed solution was rotary evaporated at 60 °C for 2 h. The product obtained by rotary evaporation was transferred to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying. After drying, it was pulverized and calcined in a tubular furnace with a 10H₂ / Ar mixed gas at 350 °C for 3 h to obtain a powdered oxide material;

[0113] 1.7 g of the powdered oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, centrifugation was carried out 5 times. It was dried in a vacuum drying oven at 70 °C with a vacuum degree of 2×10 4 Pa and then ground. The finally collected powdered solid was the molybdenum sulfide catalyst.

[0114] 500 mg of the MoS₂ catalytic material and 12.5570 mg of Cs₂SO₄ were dissolved in 5 mL of deionized water and stirred for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0115] The third mixed solution was rotary evaporated at 60 °C for 1 h. After the water was completely removed, the sample was ground to a powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen - argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content was 10% H₂ / Ar, the temperature of the tubular furnace was 300 °C, and the reaction was carried out for 2 h. After the reaction ended and the tubular furnace naturally cooled to room temperature, the obtained black solid powder was collected, which was Cs-MoS₂.

[0116] 0.015 g of the Cs-MoS₂ catalytic material was pelletized into 20 - 40 mesh particles to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as Catalyst 8#.

[0117] Example 9

[0118] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 2 h to obtain a second mixed solution;

[0119] The second mixed solution is rotary evaporated at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying treatment. After drying, pulverize it and calcine it in a tubular furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0120] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, stir at 30 °C for 4 h, perform 5 centrifugations after the treatment is completed, and dry it in a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation, and finally collect the obtained powdery solid, which is the molybdenum sulfide catalyst.

[0121] Dissolve 500 mg of MoS2 catalytic material and 9.4925 mg of Mg(NO3)2 in 5 mL of deionized water, stir for 30 min, the stirring rate is 600 r / min, and the stirring temperature is 10 °C to obtain a third mixed solution;

[0122] Perform rotary evaporation on the third mixed solution at a temperature of 40 °C for 2 h. After the water is completely removed, grind the sample in an agate mortar to a powdery state, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the temperature of the tubular furnace is 300 °C, the reaction is for 2 h. After the reaction ends, wait for the tubular furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Mg-MoS2.

[0123] Press 0.015 g of Mg-MoS2 catalytic material into pellets with a particle size of 20 - 40 mesh to obtain a molybdenum sulfide catalytic material doped with alkaline earth metal salts, denoted as catalyst 9#.

[0124] Example 10

[0125] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 20.0 g of methyl orthosilicate and stir at 25 °C for 2 h to obtain a second mixed solution;

[0126] The second mixed solution is rotary evaporated at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×104 It is dried in a vacuum drying oven at [pressure value] Pa, crushed after drying, and calcined in a tubular furnace with a 10H% H₂ / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0127] 1.7 g of the powdery oxide material, 5.6 g of a 25 wt% sodium hydroxide solution, and 40 mL of deionized water are mixed and stirred at 20 °C for 5 h. After the treatment is completed, it is centrifuged 5 times, and dried in a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa, and ground after drying. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0128] 500 mg of MoS₂ catalytic material and 5.8983 mg of NaNO₃ are dissolved in 5 mL of deionized water, stirred for 30 min at a stirring rate of 600 r / min and a stirring temperature of 10 °C to obtain a third mixed solution;

[0129] The third mixed solution is subjected to rotary evaporation at 40 °C for 2 h. After the water is completely removed, the sample is ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample is placed in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content is 10% H₂ / Ar, the temperature of the tubular furnace is 300 °C, the reaction is for 2 h. After the reaction ends, the obtained black solid powder is collected after the tubular furnace naturally cools to room temperature, which is Na-MoS₂.

[0130] 0.015 g of the Na-MoS₂ catalytic material is pressed and granulated into 20 - 40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 10#.

[0131] Example 11

[0132] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea are dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.4 g of tetraethyl orthosilicate is added and stirred at 25 °C for 2 h to obtain a second mixed solution;

[0133] The second mixed solution is subjected to rotary evaporation at 60 °C for 2 h. The product obtained by rotary evaporation is transferred to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying treatment, crushed after drying, and calcined in a tubular furnace with a 10H% H₂ / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0134] Note: The pressure value in the original text marked as [pressure value] is not clear in the provided content. Here, it is directly translated as "[pressure value]" in the English translation. You may need to substitute the accurate pressure value if it is available.Mix 1.7 g of powdered oxide material with 5.6 g of 25 wt% sodium hydroxide solution and 40 mL of deionized water, stir at 30 °C for 4 h, perform 5 centrifugations after the treatment is completed, and dry in a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdered solid is the molybdenum sulfide catalyst.

[0135] Dissolve 500 mg of MoS2 catalytic material and 8.5134 mg of Be(NO3)2 in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0136] Perform rotary evaporation on the third mixed solution at 60 °C for 1.5 h. After the water is completely removed, grind the sample in an agate mortar to a powder, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the tube furnace temperature is 300 °C, the reaction is for 2 h. After the reaction ends, wait for the tube furnace to cool naturally to room temperature and collect the obtained black solid powder, which is Be-MoS2.

[0137] Press 0.015 g of Be-MoS2 catalytic material into pellets of 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with alkaline earth metal salts, denoted as catalyst 11#.

[0138] Example 12

[0139] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 2 h to obtain a second mixed solution;

[0140] Perform rotary evaporation on the second mixed solution at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa for drying treatment. After drying, crush it and calcine it in a tube furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain the powdered oxide material;

[0141] Mix 1.7 g of powdered oxide material with 5.6 g of 25 wt% sodium hydroxide solution and 40 mL of deionized water, stir at 30 °C for 4 h, perform 5 centrifugations after the treatment is completed, and dry in a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdered solid is the molybdenum sulfide catalyst.

[0142] Dissolve 500 mg of MoS2 catalytic material and 2.9419 mg of LiCl in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0143] Perform rotary evaporation on the third mixed solution at a temperature of 60 °C for 1.5 h. After the water is completely removed, grind the sample in an agate mortar to a powder, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The content of hydrogen is 10% H2 / Ar, the temperature of the tube furnace is 300 °C, and the reaction is carried out for 2 h. After the reaction is completed, wait for the tube furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Li-MoS2.

[0144] Press 0.015 g of Li-MoS2 catalytic material into pellets of 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 12#.

[0145] Example 13

[0146] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 1.5 h to obtain a second mixed solution;

[0147] Perform rotary evaporation on the second mixed solution at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at a temperature of 80 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, crush it and calcine it in a tube furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0148] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, stir at 30 °C for 4 h. After the treatment is completed, perform centrifugation 5 times and dry it in a vacuum drying oven at 70 °C and a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation, and finally collect the obtained powdery solid, which is the molybdenum sulfide catalyst.

[0149] Dissolve 500 mg of MoS2 catalytic material and 4.0559 mg of NaCl in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0150] The third mixed solution was subjected to rotary evaporation at a temperature of 60 °C for 1.5 h. After the water was completely removed, the sample was ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The content of hydrogen was 10% H2 / Ar, the temperature of the tube furnace was 300 °C, and the reaction was carried out for 2 h. After the reaction ended, the tube furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was Na-MoS2.

[0151] 0.015 g of the Na-MoS2 catalytic material was pressed and granulated to 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 13#.

[0152] Example 14

[0153] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 20.0 g of methyl orthosilicate was added and stirred at 25 °C for 2 h to obtain a second mixed solution;

[0154] The second mixed solution was subjected to rotary evaporation at 60 °C for 2 h. The product obtained by rotary evaporation was transferred to a vacuum drying oven at a temperature of 80 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, it was crushed and calcined in a tube furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0155] 1.7 g of the powdery oxide material, 5.6 g of a 25 wt% sodium hydroxide solution, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, centrifugation was carried out 5 times and dried in a vacuum drying oven at 80 °C and a vacuum degree of 2×10 4 Pa. After drying, a grinding operation was carried out, and the finally collected powdery solid was the molybdenum sulfide catalyst.

[0156] 500 mg of the MoS2 catalytic material and 5.1738 mg of KCl were dissolved in 5 mL of deionized water, stirred for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0157] The third mixed solution was subjected to rotary evaporation at a temperature of 60 °C for 1.5 h. After the water was completely removed, the sample was ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The content of hydrogen was 10% H2 / Ar, the temperature of the tube furnace was 300 °C, and the reaction was carried out for 2 h. After the reaction ended, the tube furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was K-MoS2.

[0158] 0.015 g of the K-MoS₂ catalytic material was pelletized into 20-40 mesh particles to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 14#.

[0159] Example 15

[0160] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.4 g of tetraethyl orthosilicate was added and stirred at 25 °C for 2 h to obtain a second mixed solution.

[0161] The second mixed solution was rotary evaporated at 60 °C for 2 h. The product obtained by rotary evaporation was transferred to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying. After drying, it was pulverized and calcined in a tubular furnace with a 10H₂ / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material.

[0162] 1.7 g of the powdery oxide material, 5.6 g of a 25 wt% sodium hydroxide solution, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, centrifugation was carried out 5 times. It was dried in a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa and then ground. The finally collected powdery solid was the molybdenum sulfide catalyst.

[0163] 500 mg of the MoS₂ catalytic material and 10.1459 mg of SrCl₂ were dissolved in 5 mL of deionized water and stirred for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution.

[0164] The third mixed solution was rotary evaporated at 60 °C for 1.5 h. After the water was completely removed, the sample was ground to a powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content was 10% H₂ / Ar, the temperature of the tubular furnace was 300 °C, and the reaction was carried out for 2 h. After the reaction ended, the tubular furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was Sr-MoS₂.

[0165] 0.015 g of the Sr-MoS₂ catalytic material was pelletized into 20-40 mesh particles to obtain a molybdenum sulfide catalytic material doped with an alkaline earth metal salt, denoted as catalyst 15#.

[0166] Example 16

[0167] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 2 h to obtain a second mixed solution;

[0168] The second mixed solution is rotary evaporated at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying treatment. After drying, pulverize it and calcine it in a tubular furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0169] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 30 °C for 4 h. After the treatment is completed, perform centrifugation 5 times, and dry it in a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0170] Dissolve 500 mg of MoS2 catalytic material and 4.5797 mg of CH3COOLi in 5 mL of deionized water, stir for 30 min, the stirring rate is 600 r / min, and the stirring temperature is 40 °C to obtain a third mixed solution;

[0171] Perform rotary evaporation on the third mixed solution at a temperature of 60 °C for 1.5 h. After the water is completely removed, grind the sample in an agate mortar to a powdery state, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the temperature of the tubular furnace is 300 °C, the reaction is for 2 h. After the reaction is completed, wait for the tubular furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Li-MoS2.

[0172] Press 0.015 g of Li-MoS2 catalytic material into pellets with a particle size of 20 - 40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 16#.

[0173] Example 17

[0174] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 2 h to obtain a second mixed solution;

[0175] The second mixed solution is rotary evaporated at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×104 It is dried in a vacuum drying oven at Pa, crushed after drying, and calcined in a tubular furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0176] 1.7 g of the powdery oxide material, 5.6 g of a 25 wt% sodium hydroxide solution, and 40 mL of deionized water are mixed and stirred at 30 °C for 4 h. After the treatment is completed, it is centrifuged 5 times, and dried in a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa, and ground after drying. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0177] 500 mg of MoS2 catalytic material and 5.6932 mg of CH3COONa are dissolved in 5 mL of deionized water, stirred for 30 min, the stirring rate is 600 r / min, and the stirring temperature is 40 °C to obtain a third mixed solution;

[0178] The third mixed solution is subjected to rotary evaporation at 60 °C for 1.5 h. After the water is removed completely, the sample is ground to a powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample is placed in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the temperature of the tubular furnace is 300 °C, the reaction is for 2 h. After the reaction ends, wait for the tubular furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Na-MoS2.

[0179] 0.015 g of the Na-MoS2 catalytic material is pressed and granulated into 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 17#.

[0180] Example 18

[0181] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea are dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.2 g of silica sol is added and stirred at 25 °C for 2 h to obtain a second mixed solution;

[0182] The second mixed solution is subjected to rotary evaporation at 40 °C for 2.5 h. The product obtained by rotary evaporation is transferred to a vacuum drying oven at 70 °C with a vacuum of 2×10 4 Pa, dried, crushed, and calcined in a tubular furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0183] Mix 1.7 g of powdered oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 20 °C for 5 h. After the treatment, perform centrifugation 5 times, and dry in a vacuum drying oven at 70 °C with a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdered solid is the molybdenum sulfide catalyst.

[0184] Dissolve 500 mg of MoS2 catalytic material and 7.1943 mg of Ca(H2PO4)2 in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 10 °C to obtain a third mixed solution;

[0185] Perform rotary evaporation on the third mixed solution at a temperature of 40 °C for 2 h. After the water is completely removed, grind the sample in an agate mortar to a powder, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the tube furnace temperature is 300 °C, the reaction is for 2 h. After the reaction ends, wait for the tube furnace to cool naturally to room temperature, and collect the obtained black solid powder, which is Ca-MoS2.

[0186] Press 0.015 g of Ca-MoS2 catalytic material into pellets of 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with alkaline earth metal salts, denoted as catalyst 18#.

[0187] Example 19

[0188] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.4 g of tetraethyl orthosilicate and stir at 25 °C for 2 h to obtain a second mixed solution;

[0189] Perform rotary evaporation on the second mixed solution at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying treatment. After drying, crush it and calcine it in a tube furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain the powdered oxide material;

[0190] Mix 1.7 g of powdered oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 30 °C for 5 h. After the treatment, perform centrifugation 5 times, and dry in a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdered solid is the molybdenum sulfide catalyst.

[0191] Dissolve 500 mg of MoS2 catalytic material and 7.0799 mg of CH3COOLi·2H2O in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixed solution;

[0192] Perform rotary evaporation on the third mixed solution at a temperature of 60 °C for 1.5 h. After the water is completely removed, grind the sample in an agate mortar to a powder, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The hydrogen content is 10% H2 / Ar, the tube furnace temperature is 300 °C, and the reaction is for 2 h. After the reaction ends, wait for the tube furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Li-MoS2.

[0193] Press 0.015 g of Li-MoS2 catalytic material into pellets of 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 19#.

[0194] Example 20

[0195] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 20.0 g of tetramethoxysilane and stir at 25 °C for 1.5 h to obtain a second mixed solution;

[0196] Perform rotary evaporation on the second mixed solution at 40 °C for 2.5 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at a temperature of 70 °C and a vacuum of 2×10 4 Pa for drying. After drying, crush it and calcine it in a tube furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0197] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, stir at 20 °C for 4 h, perform centrifugation 5 times after the treatment, and dry it in a vacuum drying oven at 70 °C and a vacuum of 2×10 4 Pa. After drying, perform a grinding operation, and finally collect the obtained powdery solid, which is the molybdenum sulfide catalyst.

[0198] Dissolve 500 mg of MoS2 catalytic material and 6.6076 mg of MgCl2 in 5 mL of deionized water, stir for 30 min at a stirring rate of 600 r / min and a stirring temperature of 10 °C to obtain a third mixed solution;

[0199] The third mixed solution was subjected to rotary evaporation at a temperature of 40 °C for 2 h. After the water was completely removed, the sample was ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content was 10% H2 / Ar, the temperature of the tubular furnace was 300 °C, the reaction was for 2 h. After the reaction ended, the tubular furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was Mg-MoS2.

[0200] 0.015 g of the Mg-MoS2 catalytic material was tableted and granulated to 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with alkaline earth metal salts, denoted as catalyst 20#.

[0201] Example 21

[0202] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, 27.2 g of silica sol was added and stirred at 25 °C for 1.5 h to obtain a second mixed solution;

[0203] The second mixed solution was subjected to rotary evaporation at 40 °C for 2.5 h. The product obtained by rotary evaporation was transferred to a vacuum drying oven at a temperature of 70 °C and a vacuum of 2×10 4 Pa for drying. After drying, it was pulverized and calcined in a tubular furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0204] 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, centrifugation was carried out 5 times and dried in a vacuum drying oven at 80 °C and a vacuum of 2×10 4 Pa. After drying, a grinding operation was carried out, and the finally collected powdery solid was the molybdenum sulfide catalyst.

[0205] 500 mg of the MoS2 catalytic material and 3.8938 mg of KOH were dissolved in 5 mL of deionized water, stirred for 30 min, the stirring rate was 600 r / min, and the stirring temperature was 40 °C to obtain a third mixed solution;

[0206] The third mixed solution was subjected to rotary evaporation at a temperature of 60 °C for 1.5 h. After the water was completely removed, the sample was ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content was 10% H2 / Ar, the temperature of the tubular furnace was 300 °C, the reaction was for 2 h. After the reaction ended, the tubular furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was K-MoS2.

[0207] Press 0.015 g of K-MoS2 catalytic material into tablets and granulate it to 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 21#.

[0208] Example 22

[0209] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.2 g of silica sol and stir at 25 °C for 1.5 h to obtain a second mixed solution;

[0210] The second mixed solution is rotary evaporated at 40 °C for 2.5 h. The product obtained by rotary evaporation is transferred to a vacuum drying oven at a temperature of 80 °C and a vacuum degree of 2×10 4 Pa for drying treatment. After drying, it is pulverized and calcined in a tubular furnace with a 10H%2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0211] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 20 °C for 5 h. After the treatment is completed, perform centrifugation 5 times, and dry in a vacuum drying oven at 80 °C and a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0212] Dissolve 500 mg of MoS2 catalytic material and 13.3269 mg of BaCI2 in 5 mL of deionized water, stir for 30 min, the stirring rate is 600 r / min, and the stirring temperature is 10 °C to obtain a third mixed solution;

[0213] Perform rotary evaporation on the third mixed solution at a temperature of 40 °C for 2 h. After the water is completely removed, grind the sample in an agate mortar until it becomes powdery, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The hydrogen content is 10%H2 / Ar, the temperature of the tubular furnace is 300 °C, the reaction is 2 h. After the reaction ends, wait for the tubular furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is Ba-MoS2.

[0214] Press 0.015 g of Ba-MoS2 catalytic material into tablets and granulate it to 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkaline earth metal salt, denoted as catalyst 22#.

[0215] Example 23

[0216] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 27.4 g of tetraethyl orthosilicate and stir at 25 °C for 2 h to obtain a second mixed solution;

[0217] The second mixed solution is rotary evaporated at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 Pa for drying treatment. After drying, pulverize it and calcine it in a tubular furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0218] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, and stir at 20 °C for 4 h. After the treatment is completed, perform 5 centrifugations, and dry it in a vacuum drying oven at 70 °C with a vacuum degree of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0219] Dissolve 500 mg of MoS2 catalytic material and 6.1607 mg of K3PO4·2H20 in 5 mL of deionized water, stir for 30 min, the stirring rate is 600 r / min, and the stirring temperature is 10 °C to obtain a third mixed solution;

[0220] Perform rotary evaporation on the third mixed solution at a temperature of 40 °C for 2 h. After the water is completely removed, grind the sample in an agate mortar to a powdery state, and then evenly distribute it into a porcelain boat. Place the distributed sample in a hydrogen-argon atmosphere in a tubular furnace for reduction treatment. The content of hydrogen is 10% H2 / Ar, the temperature of the tubular furnace is 300 °C, the reaction is 2 h. After the reaction is completed, wait for the tubular furnace to cool naturally to room temperature and then collect the obtained black solid powder, which is K-MoS2.

[0221] Press 0.015 g of K-MoS2 catalytic material into pellets with a particle size of 20 - 40 mesh to obtain a molybdenum sulfide catalytic material doped with alkaline earth metal salts, denoted as catalyst 23#.

[0222] Comparative Example 1

[0223] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixed solution. After stirring for 30 min at a stirring rate of 800 r / min, add 3.72 g of ZSM-5 molecular sieve and stir at 25 °C for 2 h to obtain a second mixed solution;

[0224] The second mixed solution is rotary evaporated at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum degree of 2×104 It was dried in a vacuum drying oven at [Pa], crushed after drying, and calcined in a tubular furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0225] 1.7 g of the powdery oxide material, 5.6 g of a 25 wt% sodium hydroxide solution, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, it was centrifuged 5 times, and the vacuum degree at 80 °C was 2×10 4 It was dried in a vacuum drying oven at [Pa], ground after drying, and the finally collected powdery solid was the molybdenum sulfide catalyst.

[0226] 0.015 g of the sulfide was pelletized into 20 - 40 mesh to obtain a catalytic material, denoted as Comparative Catalyst 1#.

[0227] Comparative Example 2:

[0228] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring at a stirring rate of 800 r / min for 30 min, 27.2 g of silica sol was added and stirred at 25 °C for 1.5 h to obtain a second mixed solution;

[0229] The second mixed solution was rotary evaporated at 60 °C for 2 h, and the product obtained by rotary evaporation was transferred to a vacuum drying oven at 80 °C with a vacuum degree of 2×10 4 It was dried in a vacuum drying oven at [Pa], crushed after drying, and calcined in a tubular furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0230] 1.7 g of the powdery oxide material, 5 mL of 40 wt% hydrofluoric acid, and 40 mL of deionized water were mixed and stirred at 30 °C for 4 h. After the treatment was completed, it was centrifuged 5 times, and the vacuum degree at 80 °C was 2×10 4 It was dried in a vacuum drying oven at [Pa], ground after drying, and the finally collected powdery solid was the molybdenum sulfide catalyst.

[0231] 0.015 g of the sulfide was pelletized into 20 - 40 mesh to obtain a catalytic material, denoted as Comparative Catalyst 2#.

[0232] Comparative Example 3:

[0233] 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea were dissolved in 30 mL of water to obtain a first mixed solution. After stirring at a stirring rate of 800 r / min for 30 min, 27.2 g of silica sol was added and stirred at 25 °C for 1.5 h to obtain a second mixed solution;

[0234] Transfer the second mixture to a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa for drying treatment. After drying for 12 h, pulverize it, and calcine it in a tubular furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0235] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, stir at 30 °C for 4 h, perform centrifugation 5 times after the treatment, and dry it in a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0236] Press 0.015 g of the sulfide into pellets of 20 - 40 mesh to obtain a catalytic material, denoted as Comparative Catalyst 3#.

[0237] Comparative Example 4:

[0238] Dissolve 5.96 g of ammonium molybdate tetrahydrate and 5.92 g of thiourea in 30 mL of water to obtain a first mixture. After stirring at a stirring rate of 800 r / min for 30 min, add 3.72 g of ZSM-5 molecular sieve and stir at 25 °C for 1.5 h to obtain a second mixture;

[0239] Perform rotary evaporation of the second mixture at 60 °C for 2 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa for drying treatment. After drying, pulverize it, and calcine it in a tubular furnace with a 10H% 2 / Ar mixed gas at 350 °C for 3 h to obtain a powdery oxide material;

[0240] Mix 1.7 g of the powdery oxide material, 5.6 g of 25 wt% sodium hydroxide solution, and 40 mL of deionized water, stir at 30 °C for 4 h, perform centrifugation 5 times after the treatment, and dry it in a vacuum drying oven at 80 °C with a vacuum of 2×10 4 Pa. After drying, perform a grinding operation. The finally collected powdery solid is the molybdenum sulfide catalyst.

[0241] Dissolve 500 mg of MoS2 catalytic material and 2.5640 mg of Li2CO3 in 5 mL of deionized water, stir for 30 min, with a stirring rate of 600 r / min and a stirring temperature of 40 °C to obtain a third mixture;

[0242] The third mixed solution was subjected to rotary evaporation at a temperature of 60 °C for 1.5 h. After the water was completely removed, the sample was ground into powder in an agate mortar and then evenly distributed into a porcelain boat. The distributed sample was placed in a hydrogen-argon atmosphere in a tube furnace for reduction treatment. The content of hydrogen was 10% H2 / Ar, the temperature of the tube furnace was 300 °C, and the reaction was carried out for 2 h. After the reaction, the tube furnace was allowed to cool naturally to room temperature, and the obtained black solid powder was collected, which was Li-MoS2.

[0243] 0.015 g of the Li-MoS2 catalytic material was pelletized into 20-40 mesh to obtain a molybdenum sulfide catalytic material doped with an alkali metal salt, denoted as catalyst 4#.

[0244] The catalytic performance test experiments for catalytic conversion of CO2 gas were carried out on the transition metal sulfide catalytic materials prepared in some of the examples. Among them, a micro fixed-bed simulation reaction system was established with a flow rate of 36.0 mL / min and a pressure of 0.1 MPa for a CO2 / H2 / N2 mixed gas (by volume percentage, containing 4% N2, 24% CO2, and 72% H2). First, before the catalytic activity test, 0.015 g of the catalytic material sample was reduced in pure H2 or a hydrogen-argon gas stream at 600 °C and atmospheric pressure for 1 h, and then the CO2 / H2 / N2 mixed reactants were introduced for catalytic performance evaluation under atmospheric pressure. The components of the tail gas such as CO, CO2, and N2 were analyzed online quantitatively by a gas chromatograph equipped with a thermal conductivity detector and a flame ionization detector. The test results of the catalytic performance of the catalytic material are shown in Table 1.

[0245] The test results of the catalytic performance of the catalytic material are shown in Table 1.

[0246] Table 1: Test results of the catalytic performance of some transition metal sulfide catalytic materials prepared in Examples 1-24

[0247] Number Sample Name Carbon Dioxide Conversion Rate / % Carbon Monoxide Selectivity / % 1 Catalyst 1# 42.0 100 2 Catalyst 2# 45.0 100 3 Catalyst 3# 50.8 100 4 Catalyst 4# 53.6 100 5 Catalyst 5# 56.7 100 6 Catalyst 6# 42.8 100 11 Catalyst 11# 43.5 100 15 Catalyst 15# 52.3 100 20 Catalyst 20# 44.8 100 23 Catalyst 23# 58.0 100 24 Catalyst 24# 45.9 100 Comparative Example 1 Comparative Catalyst 1# 39.5 91 Comparative Example 2 Comparative Catalyst 2# 40.0 100 Comparative Example 3 Comparative Catalyst 3# 39.3 93 Comparative Example 4 Comparative Catalyst 4# 38.9 90

[0248] From the results in Table 1, it can be seen that the highest carbon dioxide conversion rate of the above catalytic material is 58%, which is close to the equilibrium conversion rate of 60.4% of this reaction at 600 °C, and the CO selectivity of the catalytic material all reaches 100%. The catalytic material has excellent carbon dioxide conversion rate and carbon monoxide selectivity, demonstrating excellent catalytic performance for selective catalytic hydrogenation of carbon dioxide to produce carbon monoxide, and the preparation scheme can be flexibly selected according to actual parameter requirements.

[0249] This nano-scale transition metal sulfide catalyst has abundant Mo cation sites and a unique adjacent defect structure, with many surface active sites, which increases the carbon dioxide conversion rate.

[0250] The surface of the catalyst modified by alkali metal / alkaline earth metal is more likely to adsorb CO2 and desorb CO, resulting in a significant increase in the conversion rate of carbon dioxide and the selectivity of carbon monoxide.

[0251] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field according to the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. A transition metal sulfide catalyst, characterized in that: It is prepared in the following manner: Dissolve a molybdenum source and a sulfur source in water to obtain a first mixed solution; Add silica sol and / or tetraethyl orthosilicate to the first mixed solution, and stir well to obtain a second mixed solution; Dry, grind, and calcine the second mixed solution to obtain a precursor; Etch and dry the precursor to obtain a molybdenum sulfide catalyst.

2. The transition metal sulfide catalyst according to claim 1, wherein: It also includes the process of loading the molybdenum sulfide catalyst, including the following steps: Put the molybdenum sulfide catalyst into water with a mass 10 times that of the catalyst, and then add a water-soluble alkali metal salt and / or alkaline earth metal salt to obtain a third mixed solution; Stir, dry, grind, and calcine the third mixed solution to obtain a loaded catalyst.

3. The transition metal sulfide catalyst according to claim 1, wherein: Granulate the molybdenum sulfide catalyst, and the particle size is 20 - 40 mesh.

4. The transition metal sulfide catalyst according to claim 2, wherein: Granulate the loaded catalyst, and the particle size is 20 - 40 mesh.

5. The transition metal sulfide catalyst according to claim 2, characterized in that: The molar ratio of the metal element of the alkali metal salt and / or alkaline earth metal salt to the metal element of the molybdenum sulfide catalyst is 1:30 - 50; The alkali metal salt is one or a mixture of any proportion of two or more of lithium sulfate, lithium nitrate, lithium carbonate, lithium chloride, lithium acetate, lithium acetate dihydrate, or, is one or a mixture of any proportion of two or more of sodium sulfate, sodium nitrate, sodium carbonate, sodium chloride, sodium acetate, or, is one or a mixture of any proportion of two or more of potassium sulfate, potassium carbonate, potassium hydroxide, potassium chloride, potassium acetate, potassium phosphate trihydrate, or, is one or a mixture of any proportion of two or more of cesium sulfate, cesium nitrate, cesium carbonate, cesium hydroxide, cesium chloride; The alkaline earth metal is one or a mixture of any proportion of two or more of beryllium nitrate, beryllium carbonate, beryllium chloride, or, is one or a mixture of any proportion of two or more of magnesium sulfate, magnesium nitrate, magnesium chloride, or, is one or a mixture of any proportion of two or more of calcium nitrate, calcium dihydrogen phosphate, calcium chlorate, calcium hypochlorite, calcium perchlorate, or, is a mixture of any proportion of two of strontium nitrate, strontium chloride, or, is a mixture of any proportion of two of barium nitrate, barium chloride.

6. The transition metal sulfide catalyst according to claim 2, characterized in that: The molybdenum source is ammonium molybdate tetrahydrate, the sulfur source is thiourea, and the molar ratio of molybdenum to sulfur in the molybdenum source and sulfur source is 1:2 - 3; The second mixed solution is prepared in the following manner: Add silica sol and / or tetraethyl orthosilicate to the first mixed solution, and stir well for 1.5 - 2 h to obtain the second mixed solution; The tetraethyl orthosilicate is methyl orthosilicate or ethyl orthosilicate.

7. The transition metal sulfide catalyst according to claim 6, characterized in that: The drying, grinding, and calcining of the second mixed solution are carried out in the following manner: Perform rotary evaporation on the second mixed solution, control the temperature at 40 - 60 °C, and the duration is 2 - 2.5 h. Transfer the product obtained by rotary evaporation to a vacuum drying oven at a temperature of 70 - 80 °C and a vacuum degree of 1.5 - 2×10 4 Pa for drying treatment. The dried product is the precursor of the catalyst; Grind the dried sample into a powder, and in a tubular furnace, carry out sulfidation treatment with a hydrogen - argon mixed gas. The temperature of the tubular furnace is 300 - 350 °C, the reaction time is 3 - 4 h, and then collect the precursor.

8. The transition metal sulfide catalyst according to claim 2, characterized in that: The etching and drying of the precursor are carried out according to the following steps: The precursor is placed in a 20 - 25 wt% sodium hydroxide solution that is 3 - 4 times the mass of the precursor and treated at 20 - 30 °C for 4 - 5 h, with stirring maintained during the process; after the treatment is completed, centrifugation is carried out, and it is dried in a vacuum drying oven with a vacuum degree of 1.5 - 2×10 4 Pa at 70 - 80 °C, followed by grinding operation, and finally the powdered solid collected is the molybdenum sulfide catalyst.

9. The transition metal sulfide catalyst according to claim 2, characterized in that: The third mixed solution is prepared in the following manner: Put the molybdenum sulfide catalyst into water with a mass 8 - 10 times that of the catalyst, then add alkali metal salts and / or alkaline earth metal salts, and then stir. The stirring temperature is 10 - 40 °C and the time is 0.5 - 1 h; The stirred solution is dried in the following manner: Perform rotary evaporation at a temperature of 40 - 60 °C for 1.5 - 2 h; Then grind it into a powder, and place it in a hydrogen - argon atmosphere in a tubular furnace for reduction treatment. The temperature of the tubular furnace is 250 - 300 °C, the reaction time is 2 - 3 h. After the reaction is completed, wait for the tubular furnace to cool naturally to room temperature, and then collect the obtained black solid powder, which is the supported catalyst.

10. Use of the transition metal sulfide catalyst according to any one of claims 1 - 9 in the preparation of carbon monoxide from carbon dioxide.