Carbon monoxide isothermal shift catalyst and method for preparing the same

Abstract

The present application belongs to the technical field of catalysts, and particularly relates to a copper-based isothermal shift catalyst for generating carbon dioxide and hydrogen from carbon monoxide and steam and a preparation method thereof. The catalyst has a composition by weight percentage of CuO 30-45%, ZnO 20-35, Al2O3 9-15%, and an additive A oxide 5-20%, and the additive A metal is at least one of Mg, Fe, and Cr. The catalyst composition introduces the additive A on the basis of Cu, Zn, and Al, the A oxide improves the dispersion of the active component Cu, effectively inhibits the growth of Cu grain size in the reaction, and the oxide carrier of Al prepared by a neutralization process improves the mass transfer and heat transfer performance of the catalyst, thereby being suitable for the isothermal shift reaction process with high CO content.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, specifically relating to an isothermal shift catalyst for the reaction of carbon monoxide with water vapor to produce carbon dioxide and hydrogen, and its preparation method. Background Technology

[0002] Carbon monoxide conversion refers to the process by which coal gas, with the aid of a catalyst, reacts with water vapor at a certain temperature to produce carbon dioxide and hydrogen from carbon monoxide. This conversion reaction removes carbon monoxide from the coal gas and also yields hydrogen, a gaseous component effective for methanol production. Therefore, the conversion section is both a conversion process and a purification process.

[0003] CO conversion reactions are typical gas-solid phase catalytic reactions. Due to the relatively simple structure of adiabatic fixed-bed reactors and the fact that gas flows through the catalyst bed in a plug flow, axial backmixing is minimal, resulting in a high gas conversion rate. Therefore, adiabatic fixed-bed reactors have long been used in large-scale industrial production. However, in practice, single-stage adiabatic reactors cannot achieve very high efficiencies, so multi-stage adiabatic bed processes are commonly used. However, these processes suffer from drawbacks such as large gas-to-gas ratios and high energy consumption. Furthermore, the reduction reaction before catalyst use releases a significant amount of heat, posing a serious threat to catalyst lifespan. This indicates that the adiabatic bed design has significant shortcomings.

[0004] The isothermal shift process places the heat exchanger inside the reactor, where the granular catalyst exchanges heat with the cooling water pipe walls, and the catalyst is moved in a timely manner.

[0005] Eliminate the heat of reaction. Maintain a relatively constant bed temperature, effectively solving a series of operational problems.

[0006] While many past publications have detailed the development of CO conversion catalysts and processes, there is relatively little discussion on reactor development, especially regarding the emerging isothermal reactors. Catalysts are crucial for achieving advanced processes, and reactor selection significantly impacts the optimal activity and lifespan of the catalyst. Only through the organic combination of both can energy conservation, emission reduction, and the achievement of optimal process parameters be realized.

[0007] Currently, the market uses traditional low-temperature shift catalysts in conjunction with isothermal reactors. The CO content in the feed gas of this process is as high as 60%-70%. These low-temperature shift catalysts have poor heat resistance. The reaction hot spot temperature is below 290℃, which is normal for them. However, when the system malfunctions and the heat generated by the reaction cannot be effectively removed, the reaction hot spot temperature may exceed 300℃, or even reach 350℃. The performance of these low-temperature shift catalysts deteriorates rapidly and cannot meet production requirements. There is an urgent need to develop a high-heat-resistant copper-based carbon monoxide isothermal shift catalyst to meet the requirements of the isothermal shift reaction process. Summary of the Invention

[0008] The purpose of this invention is to overcome the requirement that existing conversion catalysts on the market cannot be used in isothermal conversion reaction processes with high CO content (20-70 vol%).

[0009] The present invention is characterized by the introduction of an auxiliary agent A into the catalyst composition based on Cu, Zn, and Al. The oxide of A improves the dispersion of the active component Cu and effectively inhibits the growth of Cu crystal grains during the reaction. The Al oxide support prepared by the neutralization process enhances the mass transfer and heat transfer performance of the catalyst, thus making it suitable for isothermal conversion reaction processes with high CO content.

[0010] The main technical solution of the present invention is a carbon monoxide isothermal conversion catalyst, characterized in that the catalyst comprises the following components by weight percentage: CuO 30-45%, ZnO 20-35%, Al2O3 9-15%, and auxiliary agent A oxide 5-20%; the auxiliary agent A metal is at least one of Mg, Fe, and Cr.

[0011] The catalyst described in this invention is prepared by a precipitation method, and the specific steps are as follows:

[0012] (1) Prepare sodium carbonate solution; (2) Prepare a ternary mixed solution of copper, zinc and additive A; (3) Add the mixture from step (2) to the sodium carbonate solution from step (1) at a constant speed for neutralization, precipitation and aging; (4) Wash the mixed material obtained from step (3); (5) Prepare aluminum nitrate solution and sodium hydroxide solution; (6) Add the sodium hydroxide solution to the aluminum nitrate solution from step (5) at a constant speed for neutralization, precipitation and aging; (7) Add the material obtained from step (6) to step (4) for pulping; (8) After pulping, the material enters a plate and frame filter press for pressure filtration and washing; (9) After washing in step (8), the material is dried, ground, granulated, calcined and pressed into tablets to obtain the catalyst.

[0013] The molar concentration of sodium carbonate solution in step (1) of the catalyst preparation method of the present invention is 0.5-1.0 mol / L.

[0014] In step (2) of the catalyst preparation method of the present invention, the concentration of A ions in the mixed solution is 8-12 g / L, and the concentration of Cu ions is... 2+ Concentration 35-42 g / L, Zn2 + Concentration 36-43 g / L.

[0015] In step (3) of the catalyst preparation method of the present invention, the precipitation temperature is 75-80℃, the final pH value is 7.3-7.5, the aging temperature is 70-75℃, and the aging time is 0.3-0.5h.

[0016] In step (4) of the catalyst preparation method of the present invention, the washing temperature is 60-65℃.

[0017] In step (6) of step (5) of the catalyst preparation method of the present invention, Al in the aluminum nitrate solution... 3+ concentration

[0018] 36-40 g / L, the molar concentration of sodium hydroxide solution is 0.5-1.2 mol / L.

[0019] In step (6) of the catalyst preparation method of the present invention, the precipitation temperature is 65-70℃, the final pH value is 7.1-7.3, the aging temperature is 60-65℃, and the aging time is 0.3-0.5h.

[0020] In step (7) of the catalyst preparation method of the present invention, the pulping time is 0.3-0.5h.

[0021] In step (8) of the catalyst preparation method of the present invention, the plate and frame filter is washed for 0.5-1.0h, dewatered and filtered once, and then washed for 0.5-1.0h again.

[0022] In step (9) of the catalyst preparation method of the present invention, the material roasting temperature is 300-350℃ and the roasting time is 3.0-4.0h.

[0023] The catalyst provided by this invention is used for carbon monoxide isothermal conversion reactions with CO volume content of 20-70%.

[0024] The advantages of this invention are as follows: In the catalyst preparation process, by adding promoter A, the structure of the catalyst is improved, the heat transfer performance of the catalyst is enhanced, the dispersion of the active component Cu is improved, and the growth of Cu crystal size is effectively inhibited during the reaction. The Al oxide support prepared by the neutralization process improves the mass transfer and heat transfer performance of the catalyst, thus making it suitable for isothermal conversion reaction processes with high CO content. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to specific embodiments.

[0026] Example 1

[0027] (1) Prepare 3.5L of sodium carbonate solution with a concentration of 1mol / L and put it into a reaction vessel equipped with a stirrer and a water bath for heating;

[0028] (2) Prepare a ternary mixed solution with an A ion concentration of 10 g / L and a Cu ion concentration of 10 g / L. 2+ Concentration 37 g / L, Zn2 + Concentration 38 g / L;

[0029] (3) At a temperature of 78℃, mixture B was added to sodium carbonate solution at a constant rate of 60 ml / min. The final pH value was 7.3. The mixture was then stirred and aged at 70℃ for 0.5 h.

[0030] (4) The material aged in step (3) is washed three times with deionized water at 65°C.

[0031] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 1 mol / L by using a concentration of 40 g / L.

[0032] (6) Add 250 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 65°C. The final pH value is 7.3. Aging is carried out at 60°C for 0.3 h.

[0033] (7) Add the material obtained in step (6) to step (4) and pulp for 0.3 hours;

[0034] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0h, then dewatered and pressure filtered once, and then washed for another 1.0h.

[0035] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 350℃ for 3.0h, and finally pressed into tablets to obtain catalyst C-1.

[0036] Example 2

[0037] (1) Prepare 3.7L of 0.8mol / L sodium carbonate solution and put it into a reaction vessel equipped with a stirrer and water bath heating;

[0038] (2) Prepare a ternary mixed solution with an A ion concentration of 8 g / L and a Cu ion concentration of 8 g / L. 2+ Concentration 39 g / L, Zn2 + Concentration 40 g / L;

[0039] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.4. The mixture was then stirred and aged at 70℃ for 0.4h.

[0040] (4) The material aged in step (3) is washed three times with deionized water at 62°C;

[0041] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 0.8 mol / L by using a concentration of 37 g / L.

[0042] (6) Add 270 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 64 °C. The final pH value is 7.2. Aging is carried out at 60 °C for 0.4 h.

[0043] (7) Add the material obtained in step (6) to step (4) and pulp for 0.4 hours;

[0044] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 0.5 hours, then dewatered and filtered once, and then washed for 1.0 hour.

[0045] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 330℃ for 3.0h, and finally pressed into tablets to obtain catalyst C-2.

[0046] Example 3

[0047] (1) Prepare 3.5L of sodium carbonate solution with a concentration of 1mol / L and put it into a reaction vessel equipped with a stirrer and a water bath for heating;

[0048] (2) Prepare a ternary mixed solution with an A ion concentration of 10 g / L and a Cu ion concentration of 10 g / L. 2+ Concentration 37 g / L, Zn2 + Concentration 39 g / L;

[0049] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.3. The mixture was then stirred and aged at 75℃ for 0.3h.

[0050] (4) The material aged in step (3) is washed three times with deionized water at 68°C.

[0051] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 0.75 mol / L by using a concentration of 38 g / L.

[0052] (6) Add 260 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a constant rate, and neutralize and precipitate at 70 °C. The final pH value is 7.3. Then age at 60 °C for 0.4 h.

[0053] (7) Add the material obtained in step (6) to step (4) and pulp for 0.4 hours;

[0054] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0h, then dewatered and pressure filtered once, and then washed for another 1.0h.

[0055] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 320℃ for 4.0h, and finally pressed into tablets to obtain catalyst C-3.

[0056] Example 4

[0057] (1) Prepare 3.6 L of 0.9 mol / L sodium carbonate solution and put it into a reaction vessel equipped with a stirrer and water bath heating;

[0058] (2) Prepare a ternary mixed solution with an A ion concentration of 8 g / L and a Cu ion concentration of 8 g / L. 2+ Concentration 35g / L, Zn2 + Concentration 42 g / L;

[0059] (3) At a temperature of 78℃, mixture B was added to sodium carbonate solution at a constant rate of 60 ml / min. The final pH value was 7.3. The mixture was then stirred and aged at 70℃ for 0.5 h.

[0060] (4) The material aged in step (3) is washed three times with deionized water at 66°C.

[0061] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 0.9 mol / L by using a concentration of 36 g / L.

[0062] (6) Add 280 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 65°C. The final pH value is 7.3. Aging is carried out at 60°C for 0.3 h.

[0063] (7) Add the material obtained in step (6) to step (4) and pulp for 0.5 hours;

[0064] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0 h, then dewatered and pressure filtered once, and then washed for 0.5 h.

[0065] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 350℃ for 3.0h, and finally pressed into tablets to obtain catalyst C-4.

[0066] Example 5

[0067] (1) Prepare 3.5L of a 1.0mol / L sodium carbonate solution and place it into a reaction vessel equipped with a stirrer and a water bath for heating;

[0068] (2) Prepare a ternary mixed solution with an A ion concentration of 10 g / L and a Cu ion concentration of 10 g / L. 2+ Concentration 37 g / L, Zn2 + Concentration 39 g / L;

[0069] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.4. The mixture was then stirred and aged at 70℃ for 0.4h.

[0070] (4) The material aged in step (3) is washed three times with deionized water at 68°C.

[0071] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 1.0 mol / L by using a sodium hydroxide solution with a concentration of 39 g / L.

[0072] (6) Add 260 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 65°C. The final pH value is 7.2. Aging is carried out at 60°C for 0.3 h.

[0073] (7) Add the material obtained in step (6) to step (4) and pulp for 0.5 hours;

[0074] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0 h, then dewatered and pressure filtered once, and then washed for 0.5 h.

[0075] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 340℃ for 3.5h, and finally pressed into tablets to obtain catalyst C-5.

[0076] Example 6

[0077] (1) Prepare 3.5L of a 1.0mol / L sodium carbonate solution and place it into a reaction vessel equipped with a stirrer and a water bath for heating;

[0078] (2) Prepare a ternary mixed solution with an A ion concentration of 11 g / L and a Cu ion concentration of 11 g / L. 2+ Concentration 38g / L, Zn2 + Concentration 39 g / L;

[0079] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.5. The mixture was then stirred and aged at 70℃ for 0.3h.

[0080] (4) The material aged in step (3) is washed three times with deionized water at 68°C.

[0081] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 1.0 mol / L by using a sodium hydroxide solution with a concentration of 40 g / L.

[0082] (6) Add 250 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 65°C. The final pH value is 7.3. Aging is carried out at 60°C for 0.3 h.

[0083] (7) Add the material obtained in step (6) to step (4) and pulp for 0.5 hours;

[0084] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0 h, then dewatered and pressure filtered once, and then washed for 0.5 h.

[0085] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 335℃ for 3.5h, and finally pressed into tablets to obtain catalyst C-6.

[0086] Example 7

[0087] (1) Prepare 3.5L of a 1.0mol / L sodium carbonate solution and place it into a reaction vessel equipped with a stirrer and a water bath for heating;

[0088] (2) Prepare a ternary mixed solution with an A ion concentration of 12 g / L and a Cu ion concentration of 12 g / L. 2+ Concentration 37 g / L, Zn2 + Concentration 38 g / L;

[0089] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.4. The mixture was then stirred and aged at 70℃ for 0.4h.

[0090] (4) The material aged in step (3) is washed three times with deionized water at 70°C;

[0091] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 1.0 mol / L by using a sodium hydroxide solution with a concentration of 40 g / L.

[0092] (6) Add 250 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 65°C. The final pH value is 7.2. Aging is carried out at 60°C for 0.3 h.

[0093] (7) Add the material obtained in step (6) to step (4) and pulp for 0.4 hours;

[0094] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0 h, then dewatered and pressure filtered once, and then washed for 0.5 h.

[0095] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 335℃ for 3.5h, and finally pressed into tablets to obtain catalyst C-7.

[0096] Example 8

[0097] (1) Prepare 3.5L of a 1.0mol / L sodium carbonate solution and place it into a reaction vessel equipped with a stirrer and a water bath for heating;

[0098] (2) Prepare a ternary mixed solution with an A ion concentration of 12 g / L and a Cu ion concentration of 12 g / L. 2+ Concentration 38g / L, Zn2 + Concentration 38 g / L;

[0099] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.4. The mixture was then stirred and aged at 70℃ for 0.5h.

[0100] (4) The material aged in step (3) is washed three times with deionized water at 67°C.

[0101] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 1.0 mol / L by using a concentration of 38 g / L.

[0102] (6) Add 270 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 65°C. The final pH value is 7.3. Aging is carried out at 60°C for 0.3 h.

[0103] (7) Add the material obtained in step (6) to step (4) and pulp for 0.5 hours;

[0104] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0 h, then dewatered and pressure filtered once, and then washed for 0.5 h.

[0105] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 350℃ for 3.0h, and finally pressed into tablets to obtain catalyst C-8.

[0106] Example 9

[0107] (1) Prepare 3.7 L of 0.8 mol / L sodium carbonate solution and put it into a reaction vessel equipped with a stirrer and water bath heating;

[0108] (2) Prepare a ternary mixed solution with an A ion concentration of 10 g / L and a Cu ion concentration of 10 g / L. 2+ Concentration 37 g / L, Zn2 + Concentration 38 g / L;

[0109] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.4. The mixture was then stirred and aged at 70℃ for 0.4h.

[0110] (4) The material aged in step (3) is washed three times with deionized water at 67°C.

[0111] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 1.0 mol / L by using a sodium hydroxide solution with a concentration of 37 g / L.

[0112] (6) Add 275 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a constant rate, and neutralize and precipitate at 70°C. The final pH value is 7.3. Then age at 60°C for 0.3 h.

[0113] (7) Add the material obtained in step (6) to step (4) and pulp for 0.3 hours;

[0114] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0 h, then dewatered and pressure filtered once, and then washed for 0.5 h.

[0115] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 350℃ for 3.0h, and finally pressed into tablets to obtain catalyst C-9.

[0116] Example 10

[0117] (1) Prepare 3.5L of a 1.0mol / L sodium carbonate solution and place it into a reaction vessel equipped with a stirrer and a water bath for heating;

[0118] (2) Prepare a ternary mixed solution with an A ion concentration of 12 g / L and a Cu ion concentration of 12 g / L. 2+ Concentration 37 g / L, Zn2 + Concentration 38 g / L;

[0119] (3) At a temperature of 80℃, mixture B was added to sodium carbonate solution at a constant rate of 60ml / min. The final pH value was 7.5. The mixture was then stirred and aged at 70℃ for 0.4h.

[0120] (4) The material aged in step (3) is washed three times with deionized water at 70°C;

[0121] (5) Prepare aluminum nitrate solution, A 3+ Prepare a sodium hydroxide solution with a molar concentration of 1.0 mol / L by using a sodium hydroxide solution with a concentration of 40 g / L.

[0122] (6) Add 250 mL of aluminum nitrate to the neutralization tank, add sodium hydroxide solution to the aluminum nitrate solution at a uniform rate, and neutralize and precipitate at 70°C. The final pH value is 7.2. Aging is carried out at 65°C for 0.3 h.

[0123] (7) Add the material obtained in step (6) to step (4) and pulp for 0.5 hours;

[0124] (8) After pulping, the material enters the plate and frame filter press for pressure filtration and washing. First, it is washed for 1.0h, then dewatered and pressure filtered once, and then washed for another 1.0h.

[0125] (9) After washing the material in step (9), it is dried, ground and granulated, then roasted at 340℃ for 3.0h, and finally pressed into tablets to obtain catalyst C-10.

[0126] Comparative Example 1

[0127] Prepared according to Example 1 of patent CN 101786000 A.

[0128] The copper and zinc solutions in the comparative example were precipitated with sodium carbonate solution under the same conditions as the comparative example. The precipitation process...

[0129] In the process, an equal amount of Al(NO3)3 solution was added for co-precipitation. After aging, the precipitated product was washed to remove impurity ions. Then, 40g of gallium oxide monohydrate was added while stirring. After aging at 60℃ for 0.5h, it was calcined at 400℃ for 2h. Finally, graphite, a molding aid, was added and pressed into tablets with a diameter of φ5×4.5-5mm to obtain Comparative Example D-1.

[0130] The relevant performance test results of the samples prepared in the 10 embodiments and comparative examples of this invention are shown in Table 1 below.

[0131] Catalyst performance testing conditions:

[0132] An isothermal bed reactor was used, with a catalyst loading of 40 ml. The feed gas composition (v / v%) was: CO 20%-60%, CO2 8%-10%, H2 10%-40%, and the remainder being N2. The vapor-to-gas ratio (water vapor / dry gas molar ratio) was 0.45, the reaction pressure was 2.5 MPa, and the space velocity was 2000 h⁻¹. -1 The inlet temperature is 210℃. The catalyst requires reduction before use. Activation conditions: reducing atmosphere N2 / H2 mixture (5% N2, balance H2); reduction pressure: 0.4-0.5 MPa; reduction space velocity: 1000 h⁻¹ -1 The temperature is slowly increased to 230℃ and held for 2.0 hours (heating rate 1℃ / 3min).

[0133] CO conversion rate calculation formula:

[0134] E= ×100

[0135] Where: Φ1: CO volume fraction in the intake air (raw material gas), %

[0136] Φ2: CO volume fraction in the outgoing gas (product gas), %.

[0137] Table 1. Conversion rate data (%) of samples prepared in the examples and comparative examples at different CO contents.

[0138]

[0139] Table 2. Conversion rate data (%) of samples prepared in the examples and comparative examples after high-temperature heat resistance.

[0140]

[0141] Note: High temperature resistance conditions: 320℃ for 48 hours.

[0142] Table 3. Grain size variation data (%) of samples prepared in the examples and comparative examples before high-temperature heat resistance.

[0143]

[0144] As can be seen from the data in Tables 1-3, the catalyst prepared by the present invention has excellent performance. As the CO content in the feed gas increases, the catalyst still maintains a high conversion rate, especially after 48 hours at 320℃, the performance of the catalyst is more obvious.

[0145] The present invention and its embodiments have been described above illustratively. This description is not restrictive. Therefore, if those skilled in the art are inspired by it and design similar solutions and embodiments without departing from the spirit of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A carbon monoxide isothermal shift catalyst, characterized in that... The catalyst is used for the isothermal conversion reaction of carbon monoxide with a CO volume content of 20-70%; the catalyst comprises the following components by weight percentage, based on 100% catalyst weight: CuO 30-45%, ZnO 20-35%, Al2O3 9-15%, and auxiliary agent A oxide 5-20%; the auxiliary agent A metal is at least one of Mg, Fe, and Cr; The method for preparing the catalyst includes the following steps: (1) Prepare sodium carbonate solution; (2) Prepare a ternary mixed solution of copper, zinc and additive A; (3) The mixture from step (2) is added to the sodium carbonate solution from (1) at a uniform rate for neutralization, precipitation, and aging, wherein: the precipitation temperature is 75-80℃, the final pH value is 7.3-7.5, the aging temperature is 70-75℃, and the aging time is 0.3-0.5h; (4) Wash the mixed material obtained in step (3); (5) Prepare aluminum nitrate solution and sodium hydroxide solution; (6) Add sodium hydroxide solution at a constant rate to aluminum nitrate solution in step (5) for neutralization, precipitation and aging, wherein: precipitation temperature is 65-70℃, final pH value is 7.1-7.3, aging temperature is 60-65℃, and aging time is 0.3-0.5h; (7) Add the material obtained in step (6) to step (4) and pulp it; (8) The material is then subjected to pressure filtration and washing after pulping; (9) The material washed in step (8) is dried, ground, granulated, roasted at 300-350℃ for 3.0-4.0h, and pressed into tablets to obtain the catalyst.

2. The catalyst according to claim 1, characterized in that... The sodium carbonate solution in step (1) has a molar concentration of 0.5-1.0 mol / L; the mixed solution in step (2) has an A ion concentration of 8-12 g / L and a Cu ion concentration of 8-12 g / L. 2+ Concentration 35-42 g / L, Zn 2+ Concentration 36-43 g / L; Al in aluminum nitrate solution in step (5) 3+ Concentration 36-40 g / L; molar concentration of sodium hydroxide solution is 0.5-1.0 mol / L.

3. The catalyst according to claim 1, characterized in that... The washing temperature in step (4) is 60-65℃.

4. The catalyst according to claim 1, characterized in that... The pulping time in step (7) is 0.3-0.5h.

5. The catalyst according to claim 1, characterized in that... In step (8), a plate and frame filter press is used for pressure filtration and washing. The washing method is to wash for 0.5-1.0 hours, dewater and filter once, and then wash for another 0.5-1.0 hours.

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