A low-activity high-temperature-resistant carbon monoxide isothermal shift catalyst and a preparation method thereof

Abstract

This invention relates to a carbon monoxide isothermal shift catalyst for the reaction of carbon monoxide with water vapor to produce carbon dioxide and hydrogen, and its preparation method. The catalyst composition includes the following components by weight percentage: copper oxide 17-25%, zinc oxide 12-20%, aluminum oxide 45-60%, structural auxiliary metal oxide 2-10%, and modifying auxiliary metal oxide 1-5%. This invention introduces modifying and structural auxiliary agents on the basis of Cu, Zn, and Al. The structural auxiliary metal and Al act as a dual carrier, enhancing the heat transfer performance of the catalyst. The modifying auxiliary and the active component Cu exert a synergistic catalytic effect, reducing the catalyst activity and thus lowering the reaction temperature rise, making it better suited for shift reactions with high CO concentrations in an isothermal reactor.

Description

Technical Field

[0001] This invention belongs to the field of catalyst technology, specifically relating to a carbon monoxide isothermal conversion 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 shift (CO conversion) is an important component of modern coal chemical projects. It converts CO in feed gas into H2 through a shift reaction, adjusting the hydrogen-to-carbon ratio to meet the requirements of downstream units. The shift reaction is a reversible exothermic reaction. Traditional shift technologies typically employ multiple adiabatic shift reactors in series to achieve the desired shift depth. With the continuous development of coal gasification technology, dry pulverized coal quenching gasification technology has been widely applied. This type of gasification technology produces crude coal gas with high water and high CO content—a "double high" characteristic. If directly fed into the shift reactor, the catalyst bed temperature can reach over 500℃, severely impacting catalyst lifespan and system safety. Traditional adiabatic shift technologies generally employ high or low water-to-gas ratio processes to prevent catalyst bed overheating. However, neither high nor low water-to-gas ratio processes fundamentally solve the problem of catalyst operation at high temperatures. In recent years, isothermal shift technology has received significant attention from numerous research institutions and enterprises, achieving breakthrough developments and fundamentally solving the problem of catalyst bed overheating in "double high" crude coal gas shift reactions. Catalysts are key to achieving advanced processes, and the selection of reactors has a great influence on the optimal activity and lifespan of catalysts. Only by combining the two organically can energy conservation and consumption reduction be achieved and optimal process indicators be realized.

[0003] Currently, the catalysts used in conjunction with isothermal reactors have two main problems. On the one hand, their performance in the high-temperature zone is relatively low. When the temperature is above 280℃, the CO conversion rate shows a significant downward trend, and the catalyst lifespan is greatly shortened. On the other hand, high catalyst activity can cause the catalyst to accumulate heat, making it difficult to heat exchange the isothermal bed. Summary of the Invention

[0004] The purpose of this invention is to provide a low-activity, high-temperature resistant carbon monoxide isothermal shift catalyst and its preparation method, which reduces the reaction temperature rise by lowering the catalyst activity, thus better adapting to the shift reaction of high CO concentration shift gas in an isothermal reactor.

[0005] To achieve the above objectives, the first aspect of the present invention provides a low-activity, high-temperature resistant carbon monoxide isothermal conversion catalyst, comprising the following components by weight percentage: 17-25% copper oxide, 12-20% zinc oxide, 45-60% aluminum oxide, 2-10% structural aid metal oxide, and 1-5% modifying aid metal oxide.

[0006] Furthermore, the structural additive is at least one oxide selected from cerium, zirconium, calcium, magnesium, iron, manganese, and chromium.

[0007] Furthermore, the modifying agent is at least one oxide selected from lithium, sodium, potassium, rubidium, and chromium.

[0008] A second aspect of this invention provides a method for preparing a low-activity isothermal shift catalyst resistant to high carbon monoxide, comprising the following steps:

[0009] (1) Add sodium carbonate and deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0010] (2) Dissolve the precursor of the structural aid metal oxide in deionized water;

[0011] (3) Add the solution from step (2) to the zinc nitrate solution and mix well;

[0012] (4) The mixture from step (3) is added at a constant rate to the sodium carbonate solution obtained in step (1) for precipitation and aging;

[0013] (5) Add copper nitrate solution at a constant rate to the sodium carbonate solution prepared in step 1) for precipitation and aging;

[0014] (6) Add the material obtained in step (4) to the material in step (5) and mix evenly;

[0015] (7) The mixed material obtained in step 6) is washed by sedimentation 5 times, and alumina powder and water are added and stirred to make it evenly mixed.

[0016] (8) The material after mixing in step 7) is filtered and dried.

[0017] (9) Dissolve the modified metal salt in deionized water;

[0018] (10) During the grinding process of the material obtained in step 8), the solution obtained in step 9) is sprayed into it;

[0019] (11) The material obtained in step 10) is roasted and pressed into tablets to obtain the target product.

[0020] Furthermore, the molar concentration of the sodium carbonate solution in step 1) is 0.5-1.0 mol / L.

[0021] Furthermore, in step 2), the precursor of the structural aid salt metal oxide is at least one of its corresponding nitrate or carbonate.

[0022] Furthermore, in step 4), the precipitation temperature is 65-67℃, the final pH value is 7.0-7.2, the aging temperature is 60-65℃, and the aging time is 0.4-0.8h.

[0023] Furthermore, in step 5), the precipitation temperature is 75-77℃, the final pH value is 7.2-7.4, the aging temperature is 70-75℃, and the aging time is 0.4-0.8h; when the pH value of the reaction system in step 5) is 7.2-7.4, the addition of the mixture obtained in step (3) to the sodium carbonate solution is stopped.

[0024] Furthermore, the settling and washing process in step 6) is repeated 5 times.

[0025] Furthermore, in step 7), the material mixing temperature is 65-67℃ and the mixing time is 0.3-0.5h.

[0026] Furthermore, the drying in step 8) is carried out at 100-120°C for 5 hours.

[0027] Furthermore, in step 9), the modified auxiliary salt is at least one of its metal-specific acetate, nitrate, and hydroxide, and the solution concentration is 0.3–0.6 mol / L.

[0028] In step 11), the material roasting temperature is 450-550℃ and the roasting time is 3-5h.

[0029] In the catalyst described in this invention, a modifying agent and a structural agent are introduced on the basis of Cu, Zn, and Al. The structural agent metal and Al act as a dual carrier, enhancing the heat transfer performance of the catalyst. The modifying agent and the active component Cu exert a synergistic catalytic effect, reducing the activity of the catalyst, thereby reducing the reaction temperature rise and better adapting to the shift reaction of high CO concentration shift gas in an isothermal reactor. Detailed Implementation

[0030] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0031] The present invention will be described in detail below through examples. In the following examples, the catalyst composition was determined by calculation of the feed amount; the alcohol content in the liquid phase product was determined by analysis by liquid chromatography.

[0032] Example 1

[0033] (1) Add 212g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0034] (2) Dissolve 20g of cerium nitrate in 100ml of deionized water;

[0035] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.38mol / L and mix well;

[0036] (4) The mixture from step (3) is added to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 65℃, the final pH value is 7.0, and the mixture is aged at 60℃ for 0.4h.

[0037] (5) Add 1.5L of copper nitrate solution with a molar concentration of 0.3mol / L to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 75℃, the final pH value is 7.2, and the solution is aged at 70℃ for 0.4h.

[0038] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.3 hours.

[0039] (7) After the mixture is washed five times by sedimentation, 50g of alumina powder is added and mixed for 0.5h.

[0040] (8) The mixed materials are then filtered and dried.

[0041] (9) Dissolve 3.5g of potassium hydroxide in 100mL of deionized water;

[0042] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0043] (11) After granulating the material obtained in step (10), it was calcined at 550℃ for 3.0h, and then graphite was added and pressed into tablets to obtain catalyst S-1. The analysis data are shown in Table 1 below.

[0044] Example 2

[0045] (1) Add 240g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0046] (2) Dissolve 15g of cerium nitrate and 15g of calcium nitrate in 100ml of deionized water;

[0047] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.45mol / L and mix well;

[0048] (4) The mixture from step (3) was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 67℃, the final pH value was 7.1, and the mixture was aged at 65℃ for 0.5h.

[0049] (5) 1.5L of copper nitrate with a molar concentration of 0.4mol / L was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 75℃, the final pH value was 7.2, and the solution was aged at 72℃ for 0.6h.

[0050] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.4 h.

[0051] (7) After the mixture is washed five times by sedimentation, 60g of alumina powder is added and mixed for 0.4h.

[0052] (8) The mixed materials are then filtered and dried.

[0053] (9) Dissolve 3g of potassium hydroxide and 2g of lithium hydroxide in 100mL of deionized water;

[0054] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0055] (11) After granulating the material obtained in step (10), it was calcined at 550℃ for 3.0h, and then graphite was added and pressed into tablets to obtain catalyst S-2. The analysis data are shown in Table 1 below.

[0056] Example 3

[0057] (1) Add 260g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0058] (2) Dissolve 15g of calcium nitrate and 10g of magnesium nitrate in 100ml of deionized water;

[0059] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.40mol / L and mix thoroughly;

[0060] (4) The mixture from step (3) was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 67℃, the final pH value was 7.2, and the mixture was aged at 65℃ for 0.6h.

[0061] (5) 1.5L of copper nitrate with a molar concentration of 0.35mol / L was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 75℃, the final pH value was 7.3, and the solution was aged at 72℃ for 0.7h.

[0062] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.6 h.

[0063] (7) After the mixture is washed five times by sedimentation, 45g of alumina powder is added and mixed for 0.5h.

[0064] (8) The mixed materials are then filtered and dried.

[0065] (9) Dissolve 4g of rubidium hydroxide in 100mL of deionized water;

[0066] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0067] (11) After granulating the material obtained in step (10), it was calcined at 500℃ for 3.5h, and graphite was added to form tablets to obtain catalyst S-3. The analysis data are shown in Table 1 below.

[0068] Example 4

[0069] (1) Add 260g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0070] (2) Dissolve 15g of calcium nitrate and 10g of magnesium nitrate in 100ml of deionized water;

[0071] (3) Add 1.52 L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.40 mol / L and mix thoroughly;

[0072] (4) The mixture from step (3) was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 67℃, the final pH value was 7.2, and the mixture was aged at 65℃ for 0.6h.

[0073] (5) 1.5L of copper nitrate with a molar concentration of 0.35mol / L was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 77℃, the final pH value was 7.3, and the solution was aged at 72℃ for 0.7h.

[0074] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.6 h.

[0075] (7) After the mixture is washed five times by sedimentation, 45g of alumina powder is added and mixed for 0.5h.

[0076] (8) The mixed materials are then filtered and dried.

[0077] (9) Dissolve 4g of chromium nitrate in 100mL of deionized water;

[0078] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0079] (11) After granulating the material obtained in step (10), it was calcined at 500℃ for 3.5h, and then graphite was added and pressed into tablets to obtain catalyst S-4. The analysis data are shown in Table 1 below.

[0080] Example 5

[0081] (1) Add 230g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0082] (2) Dissolve 25g of zirconium nitrate in 100ml of deionized water;

[0083] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.50mol / L and mix well;

[0084] (4) The mixture from step (3) was added to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature was 67℃, the final pH value was 7.1, and the mixture was aged at 62℃ for 0.8h.

[0085] (5) 1.5L of copper nitrate with a molar concentration of 0.4mol / L was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 77℃, the final pH value was 7.4, and the solution was aged at 70℃ for 0.8h.

[0086] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.5 h.

[0087] (7) After the mixture is washed five times by sedimentation, 40g of alumina powder is added and mixed for 0.3h.

[0088] (8) The mixed material is then filtered and dried.

[0089] (9) Dissolve 5g of sodium hydroxide in 100mL of deionized water;

[0090] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0091] (11) After granulating the material obtained in step (10), it was calcined at 480℃ for 4.0h, and then graphite was added and pressed into tablets to obtain catalyst S-5. The analysis data are shown in Table 1 below.

[0092] Example 6

[0093] (1) Add 240g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0094] (2) Dissolve 15g of zirconium nitrate and 10g of manganese magnesium nitrate in 100ml of deionized water;

[0095] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.55mol / L and mix thoroughly;

[0096] (4) The mixture from step (3) is added to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 65℃, the final pH value is 7.0, and the mixture is aged at 65℃ for 0.5h.

[0097] (5) 1.5L of copper nitrate with a molar concentration of 0.35mol / L was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 75℃, the final pH value was 7.3, and the solution was aged at 70℃ for 0.6h.

[0098] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.5 h.

[0099] (7) After the mixture is washed five times by sedimentation, 65g of alumina powder is added and mixed for 0.6h.

[0100] (8) After pulping, the material is filtered and dried.

[0101] (9) Dissolve 8g of potassium acetate in 100mL of deionized water;

[0102] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0103] (11) After granulating the material obtained in step (10), it was calcined at 500℃ for 4.0h, and then graphite was added and pressed into tablets to obtain catalyst S-6. The analysis data are shown in Table 1 below.

[0104] Example 7

[0105] (1) Add 260g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0106] (2) Dissolve 25g of cerium carbonate in 100ml of deionized water;

[0107] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.40mol / L and mix thoroughly;

[0108] (4) The mixture from step (3) is added to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 65℃, the final pH value is 7.2, and the mixture is aged at 65℃ for 0.6h.

[0109] (5) 1.5L of copper nitrate with a molar concentration of 0.35mol / L was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 77℃, the final pH value was 7.3, and the solution was aged at 72℃ for 0.7h.

[0110] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.6 h.

[0111] (7) After the mixture is washed five times by sedimentation, 60g of alumina powder is added and mixed for 0.5h.

[0112] (8) The mixed materials are then filtered and dried.

[0113] (9) Dissolve 6g of sodium acetate in 100mL of deionized water;

[0114] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0115] (11) After granulating the material obtained in (10), it was calcined at 520℃ for 3.5h, and then graphite was added to form tablets to obtain catalyst S-7. The analysis data are shown in Table 1 below.

[0116] Example 8

[0117] (1) Add 250g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0118] (2) Dissolve 15g of zirconium carbonate and 10g of magnesium carbonate in 100ml of deionized water;

[0119] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.45mol / L and mix well;

[0120] (4) The mixture from step (3) is added to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 65℃, the final pH value is 7.2, and the mixture is aged at 65℃ for 0.6h.

[0121] (5) 1.55 L of copper nitrate with a molar concentration of 0.35 mol / L was added to 2 L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 75℃, the final pH value was 7.3, and the solution was aged at 73℃ for 0.6 h.

[0122] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.6 h.

[0123] (7) After the mixture is washed five times by sedimentation, 35g of alumina powder is added and mixed for 0.6h.

[0124] (8) The mixed materials are then filtered and dried.

[0125] (9) Dissolve 5g sodium acetate and 2g potassium hydroxide in 100mL of deionized water;

[0126] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0127] (11) After granulating the material obtained in step (10), it was calcined at 520℃ for 3.5h, and then graphite was added and pressed into tablets to obtain catalyst S-8. The analysis data are shown in Table 1 below.

[0128] Example 9

[0129] (1) Add 280g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0130] (2) Dissolve 15g of cerium carbonate and 10g of magnesium nitrate in 100ml of deionized water;

[0131] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.5mol / L and mix thoroughly;

[0132] (4) The mixture from step (3) is added to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 65℃, the final pH value is 7.1, and the mixture is aged at 65℃ for 0.7h.

[0133] (5) 1.5L of copper nitrate with a molar concentration of 0.3mol / L was added to 2L of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 75℃, the final pH value was 7.3, and the solution was aged at 72℃ for 0.7h.

[0134] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.6 h.

[0135] (7) After the mixture is washed five times by sedimentation, 70g of alumina powder is added and mixed for 0.6h.

[0136] (8) The mixed materials are then filtered and dried.

[0137] (9) Dissolve 3g sodium acetate and 4g potassium hydroxide in 100mL of deionized water;

[0138] (10) Spray the solution obtained in (9) into the material during the grinding process;

[0139] (11) After granulating the material obtained in step (10), it was calcined at 470℃ for 4.0h, and then graphite was added and pressed into tablets to obtain catalyst S-8. The analysis data are shown in Table 1 below.

[0140] Comparative Example 1 (Example 1 without added structural additives)

[0141] (1) Add 200g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous;

[0142] (2) 1.5 L of zinc nitrate solution with a molar concentration of 0.385 mol / L was added to 2 L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature was 65℃, the final pH value was 7.0, and the solution was aged at 60℃ for 0.4 h.

[0143] (3) 1.5 L of copper nitrate solution with a molar concentration of 0.35 mol / L was added to 2 mL of sodium carbonate solution at a constant rate to carry out precipitation. The precipitation temperature was 75℃, the final pH value was 7.2, and the solution was aged at 70℃ for 0.4 h.

[0144] (4) At a temperature of 65°C, add the material obtained in step (2) to the material in step (3) and mix for 0.3 hours.

[0145] (5) After the mixture is washed five times by sedimentation, add 50g of alumina powder and mix for 0.5h;

[0146] (6) The mixed materials are then filtered and dried.

[0147] (7) Dissolve 3.5g of potassium hydroxide in 100mL of deionized water;

[0148] (8) Spray the solution obtained in (7) into the material during the grinding process;

[0149] (9) After granulating the material obtained in step (8), calcining it at 500℃ for 4.0h, adding graphite and pressing it into tablets to obtain catalyst D-1. The analytical data are shown in Table 1 below.

[0150] Comparative Example 2 (Example 1 without added modifiers)

[0151] (1) Add 200g of sodium carbonate and 4L of deionized water to a reactor equipped with a stirring paddle and water bath heating, stir evenly, and divide into two equal portions, each 2L.

[0152] (2) Dissolve 20g of cerium nitrate in 100ml of deionized water;

[0153] (3) Add 1.5L of the solution from step (2) to a zinc nitrate solution with a molar concentration of 0.385mol / L and mix thoroughly;

[0154] (4) The mixture from step (3) is added to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 65℃, the final pH value is 7.0, and the mixture is aged at 60℃ for 0.4h.

[0155] (5) Add 1.5L of a 0.7mol / L copper nitrate solution to 2L of sodium carbonate solution at a uniform rate to carry out precipitation. The precipitation temperature is 75℃, the final pH value is 7.2, and the solution is aged at 70℃ for 0.4h.

[0156] (6) At a temperature of 65°C, add the material obtained in step (4) to the material in step (5) and mix for 0.3 hours.

[0157] (7) After the mixed material is washed and settled 5 times, 50g of alumina powder is added and the mixture is pulped for 0.5h.

[0158] (8) After pulping, the material was filtered, dried, ground, and granulated, then calcined at 550℃ for 3.5h, and graphite was added to form tablets to obtain catalyst D-2. The analytical data are shown in Table 1 below.

[0159] Comparative Example 3

[0160] Prepared according to Example 1 of patent CN 101786000 A.

[0161] The copper and zinc solutions in the comparative example were precipitated with sodium carbonate solution under the same precipitation conditions as the comparative example. During the precipitation process, an equal amount of Al(NO3)3 solution from the comparative example was added for co-precipitation. After aging and washing away impurity ions, 40g of gallium oxide monohydrate was added while stirring. The mixture was aged at 60℃ for 0.5h and then calcined at 400℃ for 2h. Finally, graphite, a molding aid, was added and the mixture was pressed into tablets with a diameter of φ5×4.5-5mm to obtain comparative example D-3.

[0162] Table 1 Comparison of data from the examples and comparative examples.

[0163] catalyst Inlet temperature / °C CO content in raw gas / % CO conversion rate / % Hot spot temperature / ℃ S-1 220 50 46.5 263.4 S-2 220 50 46.5 263.6 S-3 220 50 46.8 264.6 S-4 220 50 46.3 264.0 S-5 220 50 46.2 263.8 S-6 220 50 46.5 263.6 S-7 220 50 46.6 263.8 S-8 220 50 46.4 263.1 S-9 220 50 46.3 262.8 D-1 220 50 87.5 344.3 D-2 220 50 92.6 356.4 D-3 220 50 85.5 338.8

[0164] The activity detection conditions were: inlet temperature 220℃, reaction pressure 3 MPa, and space velocity 2000 / h.

[0165] As can be seen from the data in Table 1, the catalyst prepared by the present invention effectively reduces the hot spot temperature of the catalyst by inhibiting the catalyst activity, and can better adapt to the conversion of high concentration CO. The gas after this conversion reaction can be adapted to ordinary isothermal conversion catalysts.

[0166] 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.

[0167] The copper-based carbon monoxide isothermal shift catalyst described in this invention can be applied to carbon monoxide isothermal shift reactions. Under high carbon monoxide conditions, due to the vigorous reaction, isothermal shift reactors typically cannot dissipate a large amount of reactive heat, leading to reactor overheating. However, using the catalyst provided by this invention can reduce the reaction rate, making the temperature of the entire reaction bed controllable and preventing overheating. If two reactors are connected in series with the catalyst provided by this invention, it is possible to achieve a carbon monoxide concentration in the product gas that meets the standard for low-temperature shift reactor outlets while preventing reactor overheating.

[0168] The specific method for applying the carbon monoxide isothermal shift reaction of this invention involves catalytically reacting the feed gas with the carbon monoxide isothermal shift catalyst provided by this invention. The reaction conditions include: feed gas composition (v / v%): CO 40-60%, CO2 5-10%, H2 30-55%; vapor-to-gas ratio (water vapor / dry gas molar ratio) 0.45; reaction pressure 3.0 MPa; and space velocity 2000 h⁻¹. -1 The inlet temperature is 200℃. The catalyst requires reduction before use. Activation conditions: reducing atmosphere: N2 / H2 mixture (5% N2, balance H2); reducing pressure: 0.4-0.5 MPa; reducing space velocity: 1000 h⁻¹ -1 The temperature is slowly increased to 230℃ and held for 2.0 hours (heating rate 1℃ / 3min).

[0169] CO conversion rate calculation formula:

[0170]

[0171] Where: Φ1: CO volume fraction in the intake air (raw material gas), %

[0172] Φ2: CO volume fraction in the outgoing gas (product gas), %.

Claims

1. A low-activity high-temperature-resistant carbon monoxide isothermal shift catalyst, characterized by It includes the following components by weight percentage: copper oxide 17-25%, zinc oxide 12-20%, aluminum oxide 45-60%, structural additive metal oxide 2-10%, and modifying additive metal oxide 1-5%.

2. The catalyst according to claim 1, characterized in that The structural additive is at least one oxide selected from cerium, zirconium, calcium, magnesium, iron, manganese, and chromium.

3. The catalyst of claim 1, wherein The modifying agent is at least one oxide selected from lithium, sodium, potassium, rubidium, and chromium.

4. The process for producing the low-activity high-temperature-resistant carbon monoxide isothermal shift catalyst according to any one of claims 1 to 3, characterized by, Includes the following steps: (1) Add sodium carbonate and deionized water to a reactor equipped with a stirring paddle and water bath heating, and stir until homogeneous; (2) Dissolve the precursor of the structural aid metal oxide in deionized water; (3) Add the solution from step (2) to the zinc nitrate solution and mix well; (4) The mixture from step (3) is added at a constant rate to the sodium carbonate solution obtained in step (1) for precipitation and aging; (5) Add copper nitrate solution at a constant rate to the sodium carbonate solution prepared in step 1) for precipitation and aging; (6) Add the material obtained in step (4) to the material in step (5) and mix evenly; (7) After the mixed material obtained in step 6) is washed by sedimentation several times, alumina powder and water are added and stirred to make it evenly mixed. (8) Filter and dry the material after mixing in step 7); (9) Dissolve the modified metal salt in deionized water; (10) During the grinding process of the material obtained in step 8), the solution obtained in step 9) is sprayed into it; (11) The material obtained in step 10) is roasted and pressed into tablets to obtain the target product.

5. The process for preparing a catalyst as claimed in claim 4, wherein, The molar concentration of the sodium carbonate solution in step 1) is 0.5-1.0 mol / L.

6. The method of making a catalyst according to claim 4, wherein, In step 2), the precursor of the structural aid salt metal oxide is at least one of its corresponding metal nitrate or carbonate.

7. The method of making a catalyst according to claim 4, wherein, In step 4), the precipitation temperature is 65-67℃, the final pH value is 7.0-7.2, the aging temperature is 60-65℃, and the aging time is 0.4-0.8h.

8. The method of making a catalyst as recited in Claim 4 wherein, In step 5), the precipitation temperature is 75-77℃, the final pH value is 7.2-7.4, the aging temperature is 70-75℃, and the aging time is 0.4-0.8h. When the pH value of the reaction system in step 5) is 7.2-7.4, the addition of the mixture obtained in step (3) to the sodium carbonate solution is stopped.

9. The method of claim 4, wherein the catalyst is prepared by the steps of: The settling and washing process in step 7) is repeated 5 times.

10. The process for preparing a catalyst as claimed in claim 4, wherein, In step 7), the material mixing temperature is 65-67℃ and the mixing time is 0.3-0.5h.

11. The process for preparing a catalyst as claimed in claim 4, wherein, The drying process in step 8) is carried out at 100-120°C for 5 hours.

12. The process for preparing a catalyst as claimed in claim 4, wherein, In step 9), the modified auxiliary salt is at least one of its metal-specific acetate, nitrate, and hydroxide, and the solution concentration is 0.3–0.6 mol / L.

13. The process for preparing a catalyst as claimed in claim 4, wherein, In step 11), the material roasting temperature is 450-550℃ and the roasting time is 3-5h.

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