Preparation method of carbonylation catalyst for synthesizing dimethyl oxalate

Abstract

The invention discloses a preparation method of a carbonylation catalyst for synthesizing dimethyl oxalate, and the preparation method comprises the following steps: (1) dissolving aluminum oxide, manganese oxide and an SAPO-5 molecular sieve in an organic solvent, stirring, and drying to obtain a composite carrier; (2) taking palladium salt and zinc salt as active components, taking calcium salt and cerium salt as auxiliary components, and respectively dissolving the active components and the auxiliary components in deionized water to prepare an active salt solution and an auxiliary salt solution; (3) dipping the composite carrier in an additive salt solution, taking out, drying, and roasting to obtain a solid; and (4) dipping the solid in an active salt solution, taking out, drying, and roasting to obtain the carbonylation catalyst. The carbonylation catalyst prepared by the method has high activity and selectivity in the reaction of catalyzing carbon monoxide and methyl nitrite to prepare dimethyl oxalate, and the preparation method is simple and easy for industrial application.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of dimethyl oxalate preparation, and particularly relates to a preparation method of a carbonylation catalyst for synthesizing dimethyl oxalate. BACKGROUND

[0002] In a coal-to-ethylene glycol production process, the core reaction is a carbonylation synthesis reaction of dimethyl oxalate (DMO), specifically, using methyl nitrite and carbon monoxide as raw materials, using a supported palladium as a catalyst to generate dimethyl oxalate and nitrogen monoxide. The reaction belongs to a medium-temperature, low-pressure and exothermic synthesis reaction, which does not belong to a particularly high, precise and sharp technology from the technical system, and the difficulty lies in the development and application of the catalyst.

[0003] Palladium-based catalysts have been widely used in the process of preparing DMO by directly esterifying carbon monoxide. So far, Pd / alpha-Al2O3, Pd / MgO, Pd / Mg-ZnO and Pd / ZnMgAl-LDH have been proved to be high-efficiency catalysts. The support effect plays a crucial role in affecting the catalytic activity, which can increase the metal dispersion, form metal-support interface sites, affect the electron density of the active metal center, and change the surface properties through oxygen vacancies. However, in the existing research, the influence of the support effect on the catalytic performance of the direct esterification of carbon monoxide to prepare DMO is mostly focused on the pore distribution and surface acid-base properties of the support.

[0004] Patent CN202211020596.2 discloses a palladium-based catalyst for the coupling of CO to synthesize dimethyl oxalate, a preparation method and application thereof. The catalyst is composed of a main active component palladium (Pd), a cocatalyst active component (M) and a carrier carbon nitride (C3N4) material. The preparation method is as follows: taking SiO2 microspheres as a template agent and a sacrifice agent, coating the surface with active component species, performing calcination treatment, then coating with a C3N4 material precursor, calcining, etching and reducing to obtain the Pd-M / C3N4 catalyst. The catalyst has a hollow core-shell structure, the active component is in a nanoscale high dispersion state and is encapsulated in the hollow shell of the C3N4 material, and through the strong interaction between the C3N4 material and the active component and the confinement effect of the outer shell on the active component particles encapsulated therein, the active component is anchored to inhibit agglomeration, sintering and loss. However, using the C3N4 material as the carrier, the reaction rate is slow, methyl nitrite is prone to decompose to produce a byproduct methyl formate, and then the selectivity of dimethyl oxalate is affected.

[0005] Patent CN201310012869.3 discloses a bimetallic nanocatalyst and its preparation and application methods. The catalyst support is α-alumina, and the active component is Pd-Cu nanoparticles with an average particle size of 2-3 nm. Based on the mass of the catalyst support, the active component Pd content is 0.01-2%, and the Cu content is 0.01-0.04%. This catalyst is prepared by a room-temperature in-situ loading method, which is simple, energy-efficient, and suitable for industrial production. The active component Pd-Cu nanoparticles in the catalyst exhibit high dispersion, large specific surface area, small size, and uniform distribution. This invention uses Pd-Cu bimetallic nanoparticles as the active component. While maintaining high catalyst activity and stability, it utilizes the synergistic effect of the bimetallic components and the nano-effect to reduce the content of the noble metal Pd to 0.1%, significantly reducing the catalyst cost and achieving partial substitution of the noble metal. However, the carbon monoxide conversion rate exhibited by this catalyst still needs further improvement. Summary of the Invention

[0006] To address the problems of low carbon monoxide conversion and low selectivity of dimethyl oxalate in existing catalysts used for the reaction of methyl nitrite and carbon monoxide to prepare dimethyl oxalate, this invention provides a method for preparing a carbonylation catalyst for the synthesis of dimethyl oxalate.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A method for preparing a carbonylation catalyst for the synthesis of dimethyl oxalate, the method comprising the following steps: (1) Alumina, manganese oxide and SAPO-5 molecular sieve are dissolved in an organic solvent, stirred and then dried to obtain a composite carrier; (2) Palladium and zinc salts are used as active components, and calcium and cerium salts are used as auxiliary components. The active components and auxiliary components are dissolved in deionized water to prepare active salt solutions and auxiliary salt solutions, respectively. (3) The composite carrier is immersed in an auxiliary salt solution, then removed, dried, and then calcined to obtain a solid. (4) The solid is soaked in an active salt solution, then dried and calcined to obtain a carbonylation catalyst.

[0008] Furthermore, the mass ratio of the alumina, manganese oxide and SAPO-5 molecular sieve is 7-9:0.2-1:1.

[0009] Furthermore, the organic solvent is isopropanol or ethyl acetate.

[0010] Furthermore, the organic reagent contains an ionic liquid, and the ionic liquid has a mass fraction of 1-3% in the organic solvent.

[0011] Furthermore, the ionic liquid is 1-butyl-3-methylimidazolium tetrafluoroborate.

[0012] Furthermore, sodium oleate is added to the active salt solution, and the mass fraction of sodium oleate in the active salt solution is 0.5-2%.

[0013] Furthermore, the palladium, zinc, calcium, and cerium salts are nitrates.

[0014] Furthermore, the loading of palladium is 0.03-0.5% of the total mass of the catalyst, the loading of zinc is 0.1-0.5% of the total mass of the catalyst, and the loading of calcium and cerium is 0.01-0.1% of the total mass of the catalyst.

[0015] Further, the calcination conditions in step (3) are: the heating rate is increased to 500-650℃ at a heating rate of 2.0℃ / min and maintained for 3 hours, then cooled to room temperature and taken out to obtain a solid product; In step (4), the calcination conditions are as follows: the temperature is increased to 500-600℃ at a rate of 1.5℃ / min and maintained for 6 hours. The temperature is then cooled to room temperature and removed to obtain the carbonylation catalyst.

[0016] The carbonylation catalyst was prepared according to the above method.

[0017] The present invention has the following beneficial effects: 1. The present invention provides a method for preparing a carbonylation catalyst for the synthesis of dimethyl oxalate. In the preparation process, a composite support is obtained by mixing alumina, manganese oxide and SAPO-5 molecular sieve in organic components, which improves the specific surface area and void capacity of the composite support and enhances the catalytic activity of the carbonyl catalyst.

[0018] 2. The present invention provides a method for preparing a carbonylation catalyst for the synthesis of dimethyl oxalate. By using palladium and zinc as active components and calcium and cerium as auxiliary agents in an appropriate ratio, the prepared catalyst exhibits good dimethyl oxalate selectivity.

[0019] 3. The present invention provides a method for preparing a carbonylation catalyst for the synthesis of dimethyl oxalate. In the preparation process, the active salt solution and the auxiliary salt solution are impregnated separately, and sodium oleate is added as a dispersant in the active salt solution, which improves both the carbon monoxide conversion rate and the selectivity of dimethyl oxalate.

[0020] 4. The present invention provides a method for preparing a carbonylation catalyst for the synthesis of dimethyl oxalate. The preparation method of the catalyst is easy to control and simple. Detailed Implementation

[0021] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. All reagents and equipment used in the present invention are known products or obtained by purchasing commercially available products.

[0022] Example 1 α-Al2O3, manganese oxide and SAPO-5 molecular sieve were dissolved in 2 volumes of isopropanol at a mass ratio of 7:1:1. 3% by mass of 1-butyl-3-methylimidazolium tetrafluoroborate was added to the isopropanol. After stirring for 5 hours, the mixture was dried at 100°C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with a palladium loading of 0.5% of the total catalyst mass, a zinc loading of 0.1% of the total catalyst mass, and a calcium and cerium loading of 0.1% of the total catalyst mass. Here, the calcium and cerium loadings are 0.05% of the total catalyst mass, respectively.

[0023] Calcium nitrate tetrahydrate and cerium nitrate hexahydrate were dissolved in deionized water to prepare an auxiliary salt solution. The composite carrier was placed in the auxiliary salt solution by the excess impregnation method. After impregnation for 8 hours, it was dried and then placed in a muffle furnace. The temperature was increased to 650°C at a heating rate of 2.0°C / min and held for 3 hours. Then it was cooled to room temperature and removed to obtain a solid. Palladium nitrate dihydrate and zinc nitrate hexahydrate were dissolved in deionized water to prepare an active salt solution. Sodium oleate was added to the active salt solution, with a mass fraction of 1%. The solid was then placed in the active salt solution for excess impregnation at a water bath temperature of 60°C for 10 hours. After impregnation, the solid was removed and dried in an oven at 100°C for 12 hours. Then, the temperature was increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. After cooling to room temperature, the carbonylation catalyst was obtained.

[0024] Example 2 α-Al2O3, manganese oxide and SAPO-5 molecular sieve were dissolved in 2 volumes of isopropanol at a mass ratio of 7:0.2:1. 3% by mass of 1-butyl-3-methylimidazolium tetrafluoroborate was added to the isopropanol. After stirring for 5 hours, the mixture was dried at 100°C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with a palladium loading of 0.5% of the total catalyst mass, a zinc loading of 0.5% of the total catalyst mass, and a calcium and cerium loading of 0.04% of the total catalyst mass. Here, the calcium and cerium loadings are 0.02% of the total catalyst mass, respectively.

[0025] Calcium nitrate tetrahydrate and cerium nitrate hexahydrate were dissolved in deionized water to prepare an auxiliary salt solution. The composite carrier was placed in the auxiliary salt solution by the excess impregnation method. After impregnation for 8 hours, it was dried and then placed in a muffle furnace. The temperature was increased to 650°C at a heating rate of 2.0°C / min and held for 3 hours. Then it was cooled to room temperature and removed to obtain a solid. Palladium nitrate dihydrate and zinc nitrate hexahydrate were dissolved in deionized water to prepare an active salt solution. Sodium oleate was added to the active salt solution, with a mass fraction of 1%. The solid was then placed in the active salt solution for excess impregnation at a water bath temperature of 60°C for 10 hours. After impregnation, the solid was removed and dried in an oven at 100°C for 12 hours. Then, the temperature was increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. After cooling to room temperature, the carbonylation catalyst was obtained.

[0026] Example 3 α-Al2O3, manganese oxide and SAPO-5 molecular sieve were dissolved in 2 volumes of isopropanol at a mass ratio of 9:0.2:1. 3% by mass of 1-butyl-3-methylimidazolium tetrafluoroborate was added to the isopropanol. After stirring for 5 hours, the mixture was dried at 100°C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with a palladium loading of 0.05% of the total catalyst mass, a zinc loading of 0.5% of the total catalyst mass, and a calcium and cerium loading of 0.04% of the total catalyst mass. Here, the calcium and cerium loadings are 0.02% of the total catalyst mass, respectively.

[0027] Calcium nitrate tetrahydrate and cerium nitrate hexahydrate were dissolved in deionized water to prepare an auxiliary salt solution. The composite carrier was placed in the auxiliary salt solution by the excess impregnation method. After impregnation for 8 hours, it was dried and then placed in a muffle furnace. The temperature was increased to 650°C at a heating rate of 2.0°C / min and held for 3 hours. Then it was cooled to room temperature and removed to obtain a solid. Palladium nitrate dihydrate and zinc nitrate hexahydrate were dissolved in deionized water to prepare an active salt solution. Sodium oleate was added to the active salt solution, with a mass fraction of 2%. The solid was then placed in the active salt solution for excess impregnation at a water bath temperature of 60°C for 10 hours. After impregnation, the solid was removed and dried in an oven at 100°C for 12 hours. Then, the temperature was increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. After cooling to room temperature, the carbonylation catalyst was obtained.

[0028] Comparative Example 1 α-Al2O3 and SAPO-5 molecular sieve were dissolved in 2 times the volume of isopropanol at a mass ratio of 7:1. 3% by mass of 1-butyl-3-methylimidazolium tetrafluoroborate was added to the isopropanol. After stirring for 5 h, the mixture was dried at 100 °C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with a palladium loading of 0.5% of the total catalyst mass, a zinc loading of 0.1% of the total catalyst mass, and a calcium and cerium loading of 0.1% of the total catalyst mass. Here, the calcium and cerium loadings are 0.05% of the total catalyst mass, respectively.

[0029] Calcium nitrate tetrahydrate and cerium nitrate hexahydrate were dissolved in deionized water to prepare an auxiliary salt solution. The composite carrier was placed in the auxiliary salt solution by the excess impregnation method. After impregnation for 8 hours, it was dried and then placed in a muffle furnace. The temperature was increased to 650°C at a heating rate of 2.0°C / min and held for 3 hours. Then it was cooled to room temperature and removed to obtain a solid. Palladium nitrate dihydrate and zinc nitrate hexahydrate were dissolved in deionized water to prepare an active salt solution. Sodium oleate was added to the active salt solution, with a mass fraction of 1%. The solid was then placed in the active salt solution for excess impregnation at a water bath temperature of 60°C for 10 hours. After impregnation, the solid was removed and dried in an oven at 100°C for 12 hours. Then, the temperature was increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. After cooling to room temperature, the carbonylation catalyst was obtained.

[0030] Comparative Example 2 α-Al2O3, manganese oxide and SAPO-5 molecular sieve were dissolved in 2 times the volume of isopropanol at a mass ratio of 7:1:1. After stirring for 5 h, the mixture was dried at 100 °C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with a palladium loading of 0.5% of the total catalyst mass, a zinc loading of 0.1% of the total catalyst mass, and a calcium and cerium loading of 0.1% of the total catalyst mass. Here, the calcium and cerium loadings are 0.05% of the total catalyst mass, respectively.

[0031] Calcium nitrate tetrahydrate and cerium nitrate hexahydrate were dissolved in deionized water to prepare an auxiliary salt solution. The composite carrier was placed in the auxiliary salt solution by the excess impregnation method. After impregnation for 8 hours, it was dried and then placed in a muffle furnace. The temperature was increased to 650°C at a heating rate of 2.0°C / min and held for 3 hours. Then it was cooled to room temperature and removed to obtain a solid. Palladium nitrate dihydrate and zinc nitrate hexahydrate were dissolved in deionized water to prepare an active salt solution. Sodium oleate was added to the active salt solution, with a mass fraction of 1%. The solid was then placed in the active salt solution for excess impregnation at a water bath temperature of 60°C for 10 hours. After impregnation, the solid was removed and dried in an oven at 100°C for 12 hours. Then, the temperature was increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. After cooling to room temperature, the carbonylation catalyst was obtained.

[0032] Comparative Example 3 α-Al2O3, manganese oxide and SAPO-5 molecular sieve were dissolved in 2 volumes of isopropanol at a mass ratio of 7:1:1. 3% by mass of 1-butyl-3-methylimidazolium tetrafluoroborate was added to the isopropanol. After stirring for 5 hours, the mixture was dried at 100°C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with a palladium loading of 0.5% of the total catalyst mass, a zinc loading of 0.1% of the total catalyst mass, and a calcium and cerium loading of 0.1% of the total catalyst mass. Here, the calcium and cerium loadings are 0.05% of the total catalyst mass, respectively.

[0033] Calcium nitrate tetrahydrate and cerium nitrate hexahydrate were dissolved in deionized water to prepare an auxiliary salt solution. The composite carrier was placed in the auxiliary salt solution by the excess impregnation method. After impregnation for 8 hours, it was dried and then placed in a muffle furnace. The temperature was increased to 650°C at a heating rate of 2.0°C / min and held for 3 hours. Then it was cooled to room temperature and removed to obtain a solid. Palladium nitrate dihydrate and zinc nitrate hexahydrate were dissolved in deionized water to prepare an active salt solution. The solid was then immersed in the active salt solution at a water bath temperature of 60°C for 10 hours. After immersion, the solid was removed and dried in an oven at 100°C for 12 hours. The temperature was then increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. The solid was then cooled to room temperature and removed to obtain the carbonylation catalyst.

[0034] Comparative Example 4 α-Al2O3, manganese oxide and SAPO-5 molecular sieve were dissolved in 2 volumes of isopropanol at a mass ratio of 7:1:1. 3% by mass of 1-butyl-3-methylimidazolium tetrafluoroborate was added to the isopropanol. After stirring for 5 hours, the mixture was dried at 100°C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with a palladium loading of 0.5% of the total catalyst mass, a zinc loading of 0.1% of the total catalyst mass, and a calcium and cerium loading of 0.1% of the total catalyst mass. Here, the calcium and cerium loadings are 0.05% of the total catalyst mass, respectively.

[0035] A promoter salt solution was prepared by dissolving calcium nitrate tetrahydrate and cerium nitrate hexahydrate in deionized water. An active salt solution was prepared by dissolving palladium nitrate dihydrate and zinc nitrate hexahydrate in deionized water. Sodium oleate was added to the active salt solution, with a mass fraction of 1%. The solid was then placed in the active salt solution for excess impregnation at a water bath temperature of 60°C for 10 hours. After impregnation, the solid was removed and dried in an oven at 100°C for 12 hours. The temperature was then increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. The solid was then cooled to room temperature and removed to obtain the carbonylation catalyst.

[0036] Comparative Example 5 α-Al2O3, manganese oxide and SAPO-5 molecular sieve were dissolved in 2 volumes of isopropanol at a mass ratio of 7:1:1. 3% by mass of 1-butyl-3-methylimidazolium tetrafluoroborate was added to the isopropanol. After stirring for 5 hours, the mixture was dried at 100°C until the organic solvent was removed to prepare the composite support. Weigh 50g of support and prepare a catalyst with palladium loading of 0.5% of the total catalyst mass, zinc loading of 0.1% of the total catalyst mass, and calcium loading of 0.1% of the total catalyst mass.

[0037] Calcium nitrate tetrahydrate and cerium nitrate hexahydrate were dissolved in deionized water to prepare an auxiliary salt solution. The composite carrier was placed in the auxiliary salt solution by the excess impregnation method. After impregnation for 8 hours, it was dried and then placed in a muffle furnace. The temperature was increased to 650°C at a heating rate of 2.0°C / min and held for 3 hours. Then it was cooled to room temperature and removed to obtain a solid. Palladium nitrate dihydrate and zinc nitrate hexahydrate were dissolved in deionized water to prepare an active salt solution. Sodium oleate was added to the active salt solution, with a mass fraction of 1%. The solid was then placed in the active salt solution for excess impregnation at a water bath temperature of 60°C for 10 hours. After impregnation, the solid was removed and dried in an oven at 100°C for 12 hours. Then, the temperature was increased to 600°C in a muffle furnace at a heating rate of 1.5°C / min and held for 6 hours. After cooling to room temperature, the carbonylation catalyst was obtained.

[0038] After catalysts 1-3 were prepared, the content of metal components in the catalysts was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The catalyst test sample was 100 mg, and the specific content results are shown in Table 1 below.

[0039] Table 1 The specific surface area and pore volume of the composite carriers prepared in Examples 1-3 and Comparative Examples 1-2 were measured using mercury porosimetry. The specific test results are shown in Table 2 below.

[0040] Table 2 As can be seen from the results in Table 2, although the addition of manganese oxide during the preparation process has little effect on the specific surface area of ​​the composite carrier, it reduces the pore volume. When alumina, manganese oxide and SAPO-5 molecular sieve are mixed in the organic components without the addition of ionic liquid, both the surface area and pore volume decrease.

[0041] Catalyst activity determination: The catalyst was loaded into the isothermal zone of a stainless steel fixed-bed reactor with a loading amount of 200 mg. Both the upper and lower sections of the catalyst were filled with quartz sand of the same particle size. The catalyst was first reduced using a mixture of hydrogen and nitrogen (H2 / N2 = 1:3 molar ratio) at a flow rate of 120 mL / min at 230 °C for 10 hours with a heating rate of 5 °C / min. Then, the catalyst was purged with N2 and the temperature was lowered to 140 °C to remove adsorbed hydrogen from the catalyst surface. The reaction was initiated only after the tail gas was found to be free of hydrogen.

[0042] The reaction used carbon monoxide and methyl nitrite as raw materials. Under the operating conditions of methyl nitrite:carbon monoxide = 10:14 molar ratio, space velocity of 3000 / h, reaction temperature of 140℃, and 0.1MPa, the changes in the content of material components were detected by gas chromatography. The selectivity of dimethyl oxalate was determined by flame ionization detector (FID), and the conversion rate of carbon monoxide was detected by thermal conductivity detector (TCD).

[0043] The specific catalyst activity results are shown in Table 3.

[0044] Table 3 As can be seen from the test results in Table 3 above, when no manganese oxide or ionic liquid is added to the support during the catalyst preparation process, the conversion rate of carbon monoxide decreases significantly, which has a significant impact on the utilization rate of carbon monoxide, but no significant impact on selectivity. The addition of sodium oleate to the active salt solution, the loading of active components and additives together, and the addition of cerium catalyst additive have a significant impact on the selectivity of the catalyst.

Claims

1. A method for preparing a carbonylation catalyst for the synthesis of dimethyl oxalate, characterized in that, The preparation method includes the following steps: (1) Alumina, manganese oxide and SAPO-5 molecular sieve are dissolved in an organic solvent, stirred and then dried to obtain a composite carrier; (2) Palladium and zinc salts are used as active components, and calcium and cerium salts are used as auxiliary components. The active components and auxiliary components are dissolved in deionized water to prepare active salt solutions and auxiliary salt solutions, respectively. (3) The composite carrier is immersed in an auxiliary salt solution, then removed, dried, and then calcined to obtain a solid. (4) The solid is soaked in an active salt solution, then dried and calcined to obtain a carbonylation catalyst.

2. The method for preparing the carbonylation catalyst according to claim 1, characterized in that, The mass ratio of alumina, manganese oxide and SAPO-5 molecular sieve is 7-9:0.2-1:

1.

3. The method for preparing the carbonylation catalyst according to claim 1, characterized in that, The organic solvent is isopropanol or ethyl acetate.

4. The method for preparing the carbonylation catalyst according to claim 3, characterized in that, The organic reagent contains an ionic liquid, and the ionic liquid has a mass fraction of 1-3% in the organic solvent.

5. The method for preparing the carbonylation catalyst according to claim 4, characterized in that, The ionic liquid is 1-butyl-3-methylimidazolium tetrafluoroborate.

6. The method for preparing the carbonylation catalyst according to claim 1, characterized in that, Sodium oleate is also added to the active salt solution, and the mass fraction of sodium oleate in the active salt solution is 0.5-2%.

7. The method for preparing the carbonylation catalyst according to claim 1, characterized in that, Palladium, zinc, calcium, and cerium salts are nitrates.

8. The method for preparing the carbonylation catalyst according to claim 7, characterized in that, The palladium loading in the palladium salt is 0.03-0.5% of the total catalyst mass, the zinc loading in the zinc salt is 0.1-0.5% of the total catalyst mass, and the calcium and cerium loadings in the calcium and cerium salts are 0.01-0.1% of the total catalyst mass.

9. The method for preparing the carbonylation catalyst according to claim 1, characterized in that, The calcination conditions in step (3) are as follows: the temperature is increased to 500-650℃ at a rate of 2.0℃ / min and maintained for 3 hours, then cooled to room temperature and removed to obtain a solid. In step (4), the calcination conditions are as follows: the temperature is increased to 500-600℃ at a rate of 1.5℃ / min and maintained for 6 hours. The temperature is then cooled to room temperature and removed to obtain the carbonylation catalyst.

10. The carbonylation catalyst prepared by the method according to claims 1-9.

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