Catalyst for preparing methanol through CO / CO2 hydrogenation as well as preparation method and application of catalyst

Abstract

The invention provides a catalyst for preparing methanol through CO / CO2 hydrogenation and a preparation method thereof, the preparation method comprises the following steps: taking a copper salt, an iron salt, a functional ligand and an auxiliary metal salt as raw materials, adopting a hydrothermal method and a coprecipitation method to obtain a catalyst precursor, and then drying and roasting the catalyst precursor to obtain the catalyst. According to the method disclosed by the invention, on one hand, the added functional ligand forms a unique cyclopentadienone diphosphine framework, and on the other hand, the metal additive is introduced, so that the problem that a Cu component in an existing Cu-based catalyst is easy to agglomerate and sinter is effectively solved, and the service life of the catalyst is remarkably prolonged.

Description

Technical Field

[0001] The present invention relates to the field of catalysts, and more specifically, to a catalyst for preparing methanol by hydrogenating CO / CO2, and a preparation method and application thereof. Background Art

[0002] Methanol is a liquid fuel that is very suitable for hydrogen production and is one of the clean and green energy sources. Driven by the dual carbon policy, the technology of using carbon dioxide to produce methanol has attracted much attention, and the core of this technology lies in the catalyst.

[0003] Precious metal catalysts have the advantages of high activity and good stability, but the cost of the catalyst is high, making it difficult to achieve large-scale industrial application. Cu-based catalysts are currently the most widely used in industry, with advantages such as high cost performance, high activity, relatively mild conditions of use, good selectivity and fewer by-products, but the disadvantage of Cu-based catalysts is that they are easily deactivated by thermal sintering.

[0004] In order to continuously optimize the performance of copper-based catalysts, researchers have made various attempts. Patent CN202410329997.9 provides a method for introducing a trivalent variable-valence element X (X = Ti, Ce) and a divalent variable-valence element Y (Cr, Fe) to modulate the oxygen vacancies of the CuZnZrOx catalyst, which improves the activity of the catalytic reaction, but the selectivity of methanol is low. Patent CN201110286798.7 uses an impregnation method to prepare a CuO-Fe2O3 / SiO2 bimetallic catalyst. The prepared catalyst has the advantages of high carbon monoxide conversion rate and good methanol selectivity, but the CuFe-based catalyst still has problems such as the easy agglomeration and sintering of the Cu component, and the phase separation of the Cu and Fe dual active components, which leads to a gradual increase in the selectivity of by-products during the reaction.

[0005] Therefore, there is an urgent need for a catalyst for the hydrogenation of carbon oxides (CO / CO2) to produce methanol, which has mild reaction conditions, low cost, and high catalytic activity, selectivity, and stability. Summary of the invention

[0006] In view of the above-mentioned technical problems existing in the prior art, the present invention provides a catalyst suitable for catalytic hydrogenation of CO / CO2 to produce methanol. The catalyst forms a unique cyclopentadienone diphosphine framework, which forms a confinement effect on the active components during carbonization, effectively improving the problem of easy agglomeration and sintering of Cu components in existing Cu Fe-based catalysts, thereby extending the life of the catalyst.

[0007] The basic concept of the technical solution adopted by the present invention is as follows: A method for preparing a catalyst for preparing methanol by hydrogenation of CO / CO2, comprising: 1) adding iron salt and cyclopentadienone into a solvent and mixing them evenly, and then transferring them into a reaction kettle for hydrothermal reaction; 2) After the hydrothermal reaction is completed, centrifugation is performed to obtain a solid powder, unreacted raw materials are removed by washing, and vacuum drying is performed to obtain Fe-cyclopentadienone complex powder; 3) adding the salt solution of the auxiliary metal, the copper salt solution, the Fe-cyclopentadienone complex powder and the precipitant solution into a reaction vessel, stirring in a water bath and maintaining the pH value at 7.0 to obtain a mixed solution; 4) After the mixed solution is aged, the catalyst precursor is filtered and calcined under a nitrogen atmosphere to obtain the catalyst for hydrogenating carbon oxides to methanol; The additive metal is one or more of Mg, Al, Zr and Cr.

[0008] As one embodiment, the solvent in step (1) is N,N-dimethylformamide; wherein the molar ratio of the iron salt to the cyclopentadienone is 3:5.

[0009] Preferably, in step (3), the molar ratio of copper salt solution: auxiliary metal salt solution: Fe-cyclopentadienone complex powder is 4:1:2.

[0010] Preferably, the iron salt is iron sulfate, iron nitrate or iron chloride.

[0011] As one approach, in step 1), the temperature of the hydrothermal reaction is 110-150° C., and the reaction time is 18-26 h.

[0012] As one method, in step 2), N,N-dimethylformamide and ethanol are used for washing 3 to 4 times.

[0013] Preferably, the vacuum drying temperature is 80-110° C. and the drying time is 4-8 h.

[0014] As one method, the specific operation method of step (3) is: adding the salt solution of the auxiliary metal to the copper salt solution and mixing evenly, then adding the Fe-cyclopentadienone complex powder, stirring evenly to obtain a mixed solution; using a peristaltic pump to add the mixed solution and the precipitant solution into a three-necked flask, stirring in a water bath and maintaining the pH value at 7.0 to obtain a mixed solution; Alternatively, the specific operation method of step (3) is: adding Fe-cyclopentadienone complex powder to a copper salt solution and mixing to obtain a mixed solution; using a peristaltic pump to add the mixed solution and part of the precipitant solution into a three-necked flask; and then using a peristaltic pump to continue adding the salt solution of the auxiliary metal and the remaining precipitant solution into the three-necked flask, stirring in a water bath and maintaining the pH value at 7.0 to obtain a mixed solution.

[0015] Preferably, the concentrations of the auxiliary metal salt solution, the copper salt solution and the precipitant solution are 0.2-0.5 mol / L respectively; preferably, the precipitant is carbonate.

[0016] As a method, in step 4), the aging temperature is 70-90°C, and the aging time is 1-2h; the roasting temperature is 300-400°C, the heating rate is 5-10°C / min, and the roasting time is 3-5h.

[0017] The present invention also provides a catalyst for preparing methanol by hydrogenating CO / CO2, which is obtained according to the preparation method described in any one of the above contents.

[0018] The present invention further provides the use of the catalyst for preparing methanol by hydrogenating CO / CO2 as described above, that is, using the catalyst to catalyze the hydrogenation of one or a combination of carbon monoxide and carbon dioxide to prepare methanol.

[0019] As a method, the catalyst is activated before use, and the activation treatment conditions are: the activation atmosphere is hydrogen or a mixture of hydrogen and inert gas, the pressure is 0.1-1.0 MPa, the activation treatment temperature is 170-270°C, and the activation treatment time is 2-24 hours.

[0020] Preferably, the concentration of hydrogen in the mixed gas is 5.00% to 99.99%; preferably, the inert gas is selected from at least one of helium, argon and nitrogen; preferably, the reaction pressure is 0.5 to 0.8 MPa; and the temperature of the activation reaction is 200 to 240°C.

[0021] As a method, a mixed gas of CO / CO2 / Ar and H2 is introduced for catalytic reaction, the target product of the reaction is methanol, the reaction temperature is 230-310°C, the reaction pressure is 4-8MPa, and the reaction volume space velocity is 8000-10000h -1 ; In the mixed gas CO / CO2 / Ar, the volume fraction of CO is 30% to 40%, the volume fraction of CO2 is 5% to 15%, and the volume fraction of Ar is 50% to 60%; the volume ratio of H2 to the mixed gas is 6:4.

[0022] The present invention has the following beneficial effects: 1. The present invention provides a catalyst for CO / CO2 hydrogenation to methanol, which is prepared by hydrothermal method and coprecipitation method, has simple preparation process conditions, is easy to obtain raw materials, is inexpensive, and is conducive to large-scale production. At the same time, by adjusting the metal ratio of the precursor to optimize the content of the catalyst component, it is conducive to the synergistic effect of the bimetallic and the formation and stability of the active phase.

[0023] 2. The catalyst of the present invention can form a unique cyclopentadienone diphosphine framework due to the addition of cyclopentadienone (CPD), which effectively improves the problem of easy agglomeration and sintering of the Cu component in the existing Cu Fe-based catalyst, thereby significantly extending the life of the catalyst.

[0024] 3. The carbon monoxide conversion rate of the catalyst of the present invention at 250°C is greater than 45%, and the heat resistance retention rate is greater than 75%. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention is clearly and completely described below. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Hereinafter, DMF refers to N,N-dimethylformamide, and CPD refers to cyclopentadienone.

[0027] Comparative Example 1 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was ultrasonically treated until uniformly mixed. The obtained mixed solution A was transferred to a reactor, and then a hydrothermal reaction was carried out in an oven at 120°C for 24 h.

[0028] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation and washed three times with DMF and ethanol to remove the unreacted raw materials. The obtained sample is then dried in a vacuum drying oven at 80° C. for 4 hours to obtain Fe-cyclopentadienone complex powder (Fe-CPD powder).

[0029] (3) Take 200 ml of 0.3 mol / L Na2CO3 aqueous solution and 100 ml of 0.3 mol / L Cu(NO3)2 aqueous solution; put 1 g of Fe-CPD powder into the Cu(NO3)2 aqueous solution, and stir at 60°C for 1 h to obtain a mixed solution B; use a peristaltic pump to simultaneously add the mixed solution B and the Na2CO3 aqueous solution into a three-necked flask, stir in a 70°C water bath, and maintain the pH value at 7.0 to obtain a mixed solution C.

[0030] (4) After the mixed solution C was aged at 80°C for 2 h, the catalyst precursor was obtained by filtration and heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 °C min -1 The mixture was calcined at 350 °C for 3 h at a heating rate of 1.5 °C to obtain the Cu / Fe-CPD catalyst.

[0031] Comparative Example 2 Measure 220 ml of 0.3 mol / L Na2CO3 aqueous solution, 50 ml of 0.3 mol / L Fe(NO3)3·9H2O solution and 100 ml of 0.3 mol / L Cu(NO3)2 aqueous solution, use a peristaltic pump to simultaneously add Fe(NO3)3·9H2O solution, Cu(NO3)2 aqueous solution and Na2CO3 aqueous solution into a three-necked flask, stir in a 70°C water bath, and maintain the pH value at 7.0.

[0032] The obtained mixed solution was aged at 80°C for 2 h, filtered to obtain the catalyst precursor, and heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 ° C min in a nitrogen atmosphere. -1 The mixture was calcined at 350 °C for 3 h at a heating rate of 1.5 °C to obtain a Cu / Fe catalyst.

[0033] Example 1 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was ultrasonically treated until uniformly mixed. The obtained mixed solution A was transferred to a reactor, and then a hydrothermal reaction was carried out in an oven at 120°C for 24 h.

[0034] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, and washed three times with DMF and ethanol to remove the unreacted raw materials. Finally, the obtained sample is dried in a vacuum drying oven at 80° C. for 4 hours to obtain Fe-cyclopentadienone complex powder.

[0035] (3) Take 50 ml of 0.2 mol / L Na2CO3 aqueous solution, 20 ml of 0.2 mol / L Cu(NO3)2 aqueous solution and 5 ml of 0.2 mol / L Mg(NO3)2 solution, add the Mg(NO3)2 solution to the Cu(NO3)2 solution and mix well, add 1 g of Fe-CPD powder thereto, and stir at 60°C for 1 h to obtain a mixed solution B; use a peristaltic pump to simultaneously add the mixed solution B and the Na2CO3 aqueous solution into a three-necked flask, stir in a water bath at 70°C, maintain the pH value at 7.0, and obtain a mixed solution C.

[0036] (4) The obtained mixed solution C was aged at 80°C for 2 h, and then filtered to obtain a catalyst precursor; at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 °C min -1 The catalyst was calcined at 350 °C for 3 h at a heating rate of .

[0037] Example 2 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was ultrasonically treated until uniformly mixed. The obtained mixed solution A was transferred to a reactor, and then a hydrothermal reaction was carried out in an oven at 120°C for 24 h.

[0038] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, and washed three times with DMF and ethanol to remove the unreacted raw materials. Finally, the obtained sample is dried in a vacuum drying oven at 80° C. for 4 hours to obtain the Fe-cyclopentadienone complex.

[0039] (3) 40 ml of 0.2 mol / L Na2CO3 aqueous solution and 20 ml of 0.2 mol / L Cu(NO3)2 solution were measured, and 1 g of Fe-CPD powder was placed in the copper nitrate aqueous solution. After stirring at 60°C for 1 h, a mixed solution B was obtained. The mixed solution B and the Na2CO3 aqueous solution were simultaneously added dropwise to a three-necked flask using a peristaltic pump. Then 5 ml of 0.2 mol / L Mg(NO3)2 solution and 10 ml of 0.2 mol / L Na2CO3 aqueous solution were measured, and added dropwise to the above three-necked flask using a peristaltic pump. The mixture was stirred in a 70°C water bath and the pH value was maintained at 7.0 to obtain a mixed solution C.

[0040] (4) The obtained mixed solution C was aged at 80°C for 2 h, filtered to obtain a catalyst precursor, and heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 °C min -1 The mixture was calcined at 350 °C for 3 h at a heating rate of 1.5 °C to obtain F-Cu / Fe-CPD-Mg catalyst.

[0041] Example 3 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was uniformly mixed using ultrasonic treatment. The obtained mixed solution A was transferred to a reactor and then dried in an oven at 120°C for 24 hours.

[0042] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, and washed three times with DMF and ethanol to remove the unreacted raw materials. Finally, the obtained sample is dried in a vacuum drying oven at 80° C. for 4 hours to obtain the Fe-cyclopentadienone complex.

[0043] (3) Take 50 ml of 0.2 mol / L Na2CO3 aqueous solution, 20 ml of 0.2 mol / L Cu(NO3)2 aqueous solution and 5 ml of 0.2 mol / L Al(NO3)3 solution, add the Al(NO3)3 solution to the Cu(NO3)2 aqueous solution and mix well, then add 1 g of Fe-CPD powder and stir at 60°C for 1 h to obtain a mixed solution B. Use a peristaltic pump to simultaneously add the obtained mixed solution B and the Na2CO3 aqueous solution into a three-necked flask, stir in a 70°C water bath, maintain the pH value at 7.0, and obtain a mixed solution C.

[0044] (4) The obtained mixed solution C was aged at 80°C for 2 h, filtered, and the catalyst precursor was heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 °C min -1 The catalyst was calcined at 350 °C for 3 h at a heating rate of .

[0045] Example 4 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was uniformly mixed using ultrasonic treatment. The obtained mixed solution A was transferred to a reactor and then dried in an oven at 120°C for 24 hours.

[0046] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, and washed three times with DMF and ethanol to remove the unreacted raw materials. Finally, the obtained sample is dried in a vacuum drying oven at 80° C. for 4 hours to obtain the Fe-cyclopentadienone complex.

[0047] (3) 40 ml of 0.2 mol / L Na2CO3 aqueous solution and 20 ml of 0.2 mol / L Cu(NO3)2 aqueous solution were measured, and 1 g of Fe-CPD powder was placed in the copper nitrate aqueous solution. After stirring at 60°C for 1 h, a mixed solution B was obtained; the mixed solution B and the Na2CO3 aqueous solution were simultaneously added dropwise to a three-necked flask using a peristaltic pump; then, 5 ml of 0.2 mol / L Al(NO3)3 aqueous solution and 10 ml of 0.2 mol / L Na2CO3 aqueous solution were measured, and they were simultaneously added dropwise to the above three-necked flask using a peristaltic pump. The mixture was stirred in a 70°C water bath and the pH value was maintained at 7.0 to obtain a mixed solution C.

[0048] (4) The obtained mixed solution C was aged at 80°C for 2 h, filtered, and the catalyst precursor was heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 ° C min in a nitrogen atmosphere. -1The catalyst was calcined at 350 °C for 3 h at a heating rate of .

[0049] Example 5 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was ultrasonically treated until uniformly mixed. The obtained mixed solution A was transferred to a reactor, and then a hydrothermal reaction was carried out in an oven at 120°C for 24 h.

[0050] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, and washed three times with DMF and ethanol to remove the unreacted raw materials. Finally, the obtained sample is dried in a vacuum drying oven at 80° C. for 4 hours to obtain Fe-cyclopentadienone complex powder (Fe-CPD powder).

[0051] (3) Take 50 ml of 0.2 mol / L Na2CO3 aqueous solution, 20 ml of 0.2 mol / L Cu(NO3)2 aqueous solution and 5 ml of 0.2 mol / L ZrCl4 solution, add the ZrCl4 solution to the Cu(NO3)2 aqueous solution and mix well, then add 1 g of Fe-CPD powder, and stir at 60°C for 1 h to obtain a mixed solution B. Use a peristaltic pump to simultaneously add the obtained mixed solution B and the Na2CO3 aqueous solution into a three-necked flask, stir in a 70°C water bath, and maintain the pH value at 7.0 to obtain a mixed solution C.

[0052] (4) The obtained mixed solution C was aged at 80°C for 2 h, filtered, and the catalyst precursor was heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 ° C min in a nitrogen atmosphere. -1 The catalyst was calcined at 350 °C for 3 h at a heating rate of .

[0053] Example 6 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was ultrasonically treated until uniformly mixed. The obtained mixed solution A was transferred to a reactor, and then a hydrothermal reaction was carried out in an oven at 120°C for 24 h.

[0054] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, and washed three times with DMF and ethanol to remove the unreacted raw materials. Finally, the obtained sample is dried in a vacuum drying oven at 80° C. for 4 hours to obtain Fe-cyclopentadienone complex powder (Fe-CPD powder).

[0055] (3) 40 ml of 0.2 mol / L Na2CO3 aqueous solution and 20 ml of 0.2 mol / L Cu(NO3)2 aqueous solution were measured, and 1 g of Fe-CPD powder was placed in the copper nitrate aqueous solution. After stirring at 60°C for 1 h, a mixed solution B was obtained; the mixed solution B and the Na2CO3 aqueous solution were simultaneously added dropwise to a three-necked flask using a peristaltic pump; then, 5 ml of 0.2 mol / L ZrCl4 solution and 10 ml of 0.2 mol / L Na2CO3 aqueous solution were measured, and they were simultaneously added dropwise to the above three-necked flask using a peristaltic pump. The mixture was stirred in a 70°C water bath and the pH value was maintained at 7.0 to obtain a mixed solution C.

[0056] (4) The obtained mixed solution C was aged at 80°C for 2 h, filtered to obtain a catalyst precursor, and heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 °C min -1 The catalyst was calcined at 350 °C for 3 h at a heating rate of .

[0057] Example 7 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was ultrasonically treated until uniformly mixed. The obtained mixed solution A was transferred to a reactor, and then a hydrothermal reaction was carried out in an oven at 120°C for 24 h.

[0058] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, and washed three times with DMF and ethanol to remove the unreacted raw materials. Finally, the obtained sample is dried in a vacuum drying oven at 80° C. for 4 hours to obtain Fe-cyclopentadienone complex powder (Fe-CPD powder).

[0059] (3) Take 50 ml of 0.2 mol / L Na2CO3 aqueous solution, 20 ml of 0.2 mol / L Cu(NO3)2 solution and 5 ml of 0.2 mol / L Cr(NO3)3·9H2O solution, mix the Cu(NO3)2 solution and Cr(NO3)3·9H2O solution, then add 1 g of Fe-CPD powder, and stir at 60°C for 1 h to obtain a mixed solution B. Use a peristaltic pump to simultaneously add the mixed solution B and the Na2CO3 aqueous solution into a three-necked flask, stir in a water bath at 70°C, maintain the pH value at 7.0, and obtain a mixed solution C.

[0060] (4) The obtained mixed solution C was aged at 80°C for 2 h, filtered to obtain a catalyst precursor, and heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 °C min-1 The catalyst was calcined at 350 °C for 3 h at a heating rate of .

[0061] Example 8 (1) 14.6 g of Fe(NO3)3·9H2O and 5 mL of cyclopentadienone (CPD) were added to DMF (40 mL), and the mixture was ultrasonically treated until uniformly mixed. The obtained mixed solution A was transferred to a reactor, and then a hydrothermal reaction was carried out in an oven at 120°C for 24 h.

[0062] (2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation and washed three times with DMF and ethanol to remove the unreacted raw materials. The obtained sample is then dried in a vacuum drying oven at 80° C. for 4 hours to obtain Fe-cyclopentadienone complex powder (Fe-CPD powder).

[0063] (3) 40 ml of 0.2 mol / L Na2CO3 aqueous solution and 20 ml of 0.2 mol / L Cu(NO3)2 aqueous solution were measured, and 1 g of Fe-CPD powder was placed in the copper nitrate aqueous solution. After stirring at 60°C for 1 h, a mixed solution B was obtained; the mixed solution B and the Na2CO3 aqueous solution were simultaneously added dropwise to the three-necked flask using a peristaltic pump; then, 5 ml of 0.2 mol / L Cr(NO3)3·9H2O aqueous solution and 10 ml of 0.2 mol / L Na2CO3 aqueous solution were measured, and they were simultaneously added dropwise to the above three-necked flask using a peristaltic pump. The mixture was stirred in a 70°C water bath and the pH value was maintained at 7.0 to obtain a mixed solution C.

[0064] (4) The obtained mixed solution C was aged at 80°C for 2 h, filtered to obtain a catalyst precursor, and heated at 110°C (heating rate of 5°C min -1 ) in an argon atmosphere tube furnace for 5 h, and then the precursor was heated at 5 °C min -1 The catalyst was calcined at 350 °C for 3 h at a heating rate of .

[0065] Performance Testing The catalysts obtained in Examples 1-8 and Comparative Examples 1-2 were subjected to catalyst performance tests in a fixed bed reactor.

[0066] Measure 1 ml of the catalyst obtained in Examples 1-8 and Comparative Examples 1-2 with a mesh size of 20 to 40 and 1 ml of quartz sand with the same mesh size, mix them evenly and load them into the isothermal zone of a fixed bed reactor. The catalytic reaction conditions are as follows: temperature 250°C, reaction pressure 5 MPa, reaction volume space velocity 10000 h-1, and mixed reaction gas CO / CO2 / Ar / H2 volume fraction ratio 14% / 4% / 22% / 60%, wherein Ar is the internal standard gas for gas chromatography analysis. Carbon dioxide, carbon monoxide, and methane in the gas phase product are quantitatively analyzed by an online gas chromatographic analysis equipped with a TCD detector, and the compounds in the liquid phase product are quantitatively analyzed by an online gas chromatographic analysis equipped with a TCD detector, and finally the carbon monoxide conversion rate and the methanol content in the liquid phase are calculated.

[0067] The catalyst evaluation process is as follows: the catalyst is reacted at 250°C to test its initial activity. After a period of reaction, the temperature is raised to 380°C for high-temperature treatment of the catalyst to accelerate its deactivation. After a period of heat resistance, the reaction temperature is lowered back to 250°C to test its activity after heat resistance. The percentage of the activity after heat resistance to the initial activity is the heat resistance retention rate, which is usually used to replace the life test.

[0068] The CO / CO2 hydrogenation performance test results are listed in Table 1. Table 1 CO / CO2 hydrogenation performance on different catalysts

[0069] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for preparing a catalyst for producing methanol by hydrogenation of CO / CO2, characterized in that: include: 1) adding iron salt and cyclopentadienone into a solvent and mixing, and then transferring to a reactor for hydrothermal reaction; 2) After the hydrothermal reaction is completed, the solid powder is obtained by centrifugation, the unreacted raw materials are removed by washing, and the powder is vacuum dried to obtain Fe-cyclopentadienone complex powder; 3) Add the salt solution of the auxiliary metal, the copper salt solution, the Fe-cyclopentadienone complex powder and the precipitant solution dropwise into the reaction container, stir in a water bath and maintain the pH value at 7.0 to obtain a mixed solution; 4) After aging the mixed solution, filtering to obtain a catalyst precursor and calcining under a nitrogen atmosphere to obtain the catalyst for hydrogenating carbon oxides to methanol; The additive metal is one or more of Mg, Al, Zr and Cr.

2. The method for preparing a catalyst for producing methanol from CO / CO2 hydrogenation according to claim 1, characterized in that: The solvent in step (1) is N,N-dimethylformamide; wherein the molar ratio of the iron salt to the cyclopentadienone is 3:5; Preferably, in step (3), the molar ratio of copper salt solution: auxiliary metal salt solution: Fe-cyclopentadienone complex powder is 4:1:2; Preferably, the iron salt is iron sulfate, iron nitrate or iron chloride.

3. The method for preparing a catalyst for preparing methanol by hydrogenation of carbon oxides according to claim 1, characterized in that: In step 1), the temperature of the hydrothermal reaction is 110-150° C., and the reaction time is 18-26 h.

4. The method for preparing a catalyst for preparing methanol by hydrogenation of carbon oxides according to claim 1, characterized in that: In step 2), washing with N,N-dimethylformamide and ethanol 3 to 4 times; Preferably, the vacuum drying temperature is 80-110° C. and the drying time is 4-8 h.

5. The method for preparing a catalyst for preparing methanol from CO / CO2 hydrogenation according to claim 1, characterized in that: The specific operation method of step (3) is as follows: adding the salt solution of the auxiliary metal and the Fe-cyclopentadienone complex powder to the copper salt solution and mixing and stirring to obtain a mixed solution; using a peristaltic pump to drop the mixed solution and the precipitant solution into a reaction container, stirring in a water bath and maintaining the pH value at 7.0 to obtain the mixed solution; Alternatively, the specific operation method of step (3) is: adding Fe-cyclopentadienone complex powder to copper salt solution to obtain a mixed solution; using a peristaltic pump to add the mixed solution and part of the precipitant solution into a three-necked flask; then using a peristaltic pump to continue adding the auxiliary metal salt solution and the remaining precipitant solution into the three-necked flask, stirring in a water bath and maintaining the pH value at 7.0 to obtain the mixed solution; Preferably, the concentrations of the auxiliary metal salt solution, the copper salt solution and the precipitant solution are 0.2-0.5 mol / L respectively; preferably, the precipitant is carbonate.

6. The method for preparing a catalyst for producing methanol by hydrogenation of CO / CO2 according to claim 1, characterized in that: In step 4), the aging temperature is 70-90°C, and the aging time is 1-2 hours; the roasting temperature is 300-400°C, the heating rate is 5-10°C / min, and the roasting time is 3-5 hours.

7. A catalyst for preparing methanol by hydrogenation of CO / CO2, characterized in that: Obtained according to the preparation method according to any one of claims 1 to 6.

8. The use of the catalyst for preparing methanol by hydrogenation of CO / CO2 as claimed in claim 7, characterized in that: The catalyst is used for catalyzing the hydrogenation of one or a combination of CO or CO2 to produce methanol.

9. The use according to claim 8, characterized in that: The catalyst is activated before use, and the activation treatment conditions are as follows: the activation atmosphere is hydrogen or a mixture of hydrogen and an inert gas, the pressure is 0.1-1.0 MPa, the activation treatment temperature is 170-270° C., and the activation treatment time is 2-24 hours; Preferably, the concentration of hydrogen in the mixed gas is 5.00% to 99.99%; preferably, the inert gas is selected from at least one of helium, argon and nitrogen; preferably, the pressure of the activation reaction is 0.5 to 0.8 MPa; and the temperature of the reaction is 200 to 240°C.

10. The use according to claim 8, characterized in that: A mixed gas of CO / CO2 / Ar and H2 is introduced for catalytic reaction. The target product of the reaction is methanol. The reaction temperature is 230-310°C, the reaction pressure is 4-8 MPa, and the reaction volume space velocity is 8000-10000 h -1 ; In the mixed gas CO / CO2 / Ar, the volume fraction of CO is 30%~40%, the volume fraction of CO2 is 5%~15%, and the volume fraction of Ar is 50%~60%; the volume ratio of H2 to the mixed gas is 6:4.

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