A catalyst for the acetylene process to produce vinyl acetate, its preparation method and application.

Abstract

This invention discloses a catalyst for the acetylene process to prepare vinyl acetate, its preparation method, and its application. The catalyst comprises a support and an active component supported thereon. The active component includes zinc acetate and an optional co-catalyst, wherein the co-catalyst is selected from at least one compound of a Group VA metal element, and the chlorine content in the catalyst is 5-100 ppb. The catalyst of this invention exhibits high activity and stability for the acetylene process to prepare vinyl acetate.

Description

Technical Field

[0001] This invention belongs to the field of vinyl acetate synthesis technology, specifically relating to a catalyst for the preparation of vinyl acetate by the acetylene method, its preparation method, and its application. Background Technology

[0002] Vinyl acetate is an important chemical raw material, widely used in the manufacture of polyvinyl alcohol, vinyl copolymer resins, adhesives, coatings, textile processing, and paper coatings. There are two main production processes for vinyl acetate: the ethylene process and the acetylene process. The ethylene process dominates due to its superior processability and economic advantages, accounting for 82% of total vinyl acetate production capacity. While the acetylene process requires higher investment and presents greater environmental challenges, it will maintain a significant competitive advantage in regions lacking petroleum resources for some time and will directly promote the research and development of C1 chemical processes.

[0003] Chloride ions remain in the catalyst used in the acetylene-to-vinyl acetate process during acid washing. This chloride ion accumulation in the subsequent distillation column leads to equipment corrosion. Therefore, developing low-chloride-content acetylene-to-vinyl acetate catalysts is of significant importance for protecting downstream equipment. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention aims to provide a catalyst for the acetylene-based preparation of vinyl acetate and its preparation method, and further, to provide an application of this catalyst in the synthesis of vinyl acetate. The catalyst of the present invention exhibits high activity and stability for the acetylene-based preparation of vinyl acetate.

[0005] Therefore, a first aspect of the present invention provides a catalyst for the preparation of vinyl acetate by the acetylene process, comprising a support and an active component loaded thereon, the active component comprising zinc acetate and optionally a co-catalyst selected from at least one compound of a Group VA metal element, wherein the catalyst contains 5-50 ppb of chlorine.

[0006] According to some embodiments of the present invention, the chlorine content in the catalyst is 5-50 ppb, preferably 25-50 ppb.

[0007] According to some embodiments of the present invention, the carrier is activated carbon, preferably with a specific surface area of ​​800-1400 cm². 2 / g, with an adsorption pore volume of 0.4-0.8cm³. 3 / g.

[0008] According to some embodiments of the present invention, the compounds of the Group VA metal elements include oxides of Group VA metal elements, halides of Group VA metal elements, and / or salts of Group VA metal elements.

[0009] According to some embodiments of the present invention, the Group VA metal element is bismuth and / or antimony, preferably bismuth.

[0010] According to some preferred embodiments of the present invention, the compound of the Group VA metal element is bismuth carbonate and / or basic bismuth carbonate.

[0011] According to some embodiments of the present invention, the weight ratio of the active component to the support in the catalyst is 1:(1-5).

[0012] According to some embodiments of the present invention, in the active component, the mass ratio of zinc acetate to co-catalyst is (900-1200:1) for zinc to Group VA metal element.

[0013] A second aspect of the present invention provides a method for preparing a catalyst as described in the first aspect of the present invention, characterized by comprising the following steps:

[0014] (1) The carrier was treated with a mixed solution containing hydrochloric acid and acetic acid, then filtered, washed and dried to obtain carrier 1;

[0015] (2) Calcine the carrier 1 under an inert atmosphere to obtain the carrier 2;

[0016] (3) The support 2 is impregnated with a solution containing zinc acetate and optional co-catalyst, filtered, and dried to obtain the catalyst.

[0017] According to some embodiments of the present invention, in step (1), the mass ratio of acetic acid to hydrochloric acid in the mixed solution containing hydrochloric acid and acetic acid is (1:9)-(9:1).

[0018] According to some embodiments of the present invention, in step (1), the mass ratio of acetic acid to hydrochloric acid in the mixed solution containing hydrochloric acid and acetic acid is (1:2)-(4:1).

[0019] According to some embodiments of the present invention, in step (1), the mass ratio of the carrier to the mixed solution containing hydrochloric acid and acetic acid is 1:(1-5).

[0020] According to some embodiments of the present invention, in step (1), the mass content of hydrochloric acid in the mixed solution containing hydrochloric acid and acetic acid is 1%-10%.

[0021] According to some embodiments of the present invention, in step (1), the mass content of acetic acid in the mixed solution containing hydrochloric acid and acetic acid is 1%-10%.

[0022] According to some embodiments of the present invention, in step (1), the mixed solution containing hydrochloric acid and acetic acid is a mixture of hydrochloric acid and acetic acid.

[0023] According to some embodiments of the present invention, in step (1), the treatment refers to immersing the carrier in the mixed solution of hydrochloric acid and acetic acid.

[0024] According to some embodiments of the present invention, in step (1), the temperature of the treatment is 70-100°C.

[0025] According to some embodiments of the present invention, in step (1), the processing time is 1-4 hours.

[0026] According to some embodiments of the present invention, in step (2), the inert atmosphere is at least one of N2 and Ar.

[0027] According to some embodiments of the present invention, in step (2), the calcination temperature is 150-450°C, preferably 200-300°C.

[0028] According to some embodiments of the present invention, in step (2), the calcination time is 0.5-4h, preferably 1-2h.

[0029] According to some embodiments of the present invention, in step (3), the immersion temperature is 50-90°C.

[0030] According to some embodiments of the present invention, in step (3), the soaking time is 1-6 hours.

[0031] According to the present invention, in step (3), the amount of the solution containing zinc acetate and co-catalyst is selected from a wide range, as long as it can impregnate the carrier 2. For example, in some embodiments, the volume ratio of the solution containing zinc acetate and co-catalyst to the weight ratio of the carrier 2 is 2ml:1g-10ml:1g.

[0032] According to some embodiments of the present invention, the solution containing zinc acetate and co-catalyst is an aqueous solution of zinc acetate and bismuth carbonate.

[0033] According to some embodiments of the present invention, the zinc acetate in the solution containing zinc acetate and co-catalyst is 10%-15% by mass, calculated as Zn.

[0034] According to some embodiments of the present invention, the concentration of the co-catalyst in the solution containing zinc acetate and the co-catalyst is 8-12 ppmw, calculated as metal.

[0035] According to the present invention, the washing can be performed using conventional methods in the art, and in some embodiments, the solvent for washing is water.

[0036] According to the present invention, the drying method is not specifically limited and can be any method conventional in the art. In some embodiments, a drying method is used.

[0037] A third aspect of the present invention provides the use of a catalyst as described in the first aspect of the present invention and / or a catalyst prepared by the preparation method as described in the second aspect of the present invention in the acetylene process for the preparation of vinyl acetate, wherein the use comprises reacting a feed gas containing acetylene and acetic acid in the presence of the catalyst.

[0038] According to some embodiments of the present invention, the raw material gas contains acetylene:acetic acid in a molar ratio of 1:(4-8).

[0039] According to some embodiments of the present invention, the pressure of the reaction is 0.01-0.05 MPa.

[0040] According to some embodiments of the present invention, the temperature of the reaction is 160-200°C.

[0041] According to some embodiments of the present invention, the volumetric hourly space velocity of the feed gas is 250-350 hr. -1 .

[0042] The present invention has the following beneficial effects: the catalyst of the present invention has higher activity and stability when used in the acetylene process to prepare vinyl acetate. Detailed Implementation

[0043] To make the present invention easier to understand, the present invention will be described in detail below with reference to embodiments. These embodiments are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply.

[0044] 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.

[0045] In the following embodiments of the present invention, the average STY of the 100-hour evaluation experiment is used to represent the catalyst activity, and the STY decay values ​​of the catalyst at 1h and 100h are used to evaluate the catalyst lifetime. The smaller the decay, the longer the catalyst lifetime.

[0046] Example 1

[0047] 1. Catalyst Preparation

[0048] (1) Take 100g of activated carbon (specific surface area of ​​800-1400 cm²) 2 / g, with an adsorption pore volume of 0.4-0.8cm³.3 / g) was added to 200ml of an aqueous solution containing hydrochloric acid and acetic acid, and heated at 90℃ for 2h. The mass fraction of acetic acid in the solution was 8%, and the mass fraction of hydrochloric acid was 2%. Then, the solution was filtered, washed with water, and dried to obtain carrier 1.

[0049] (2) Take 100g of carrier 1 and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0050] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0051] 2. Catalyst Evaluation

[0052] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0053] Catalyst loading volume: 40 ml;

[0054] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0055] Reactant feed space velocity: 300hr -1 ;

[0056] Reaction pressure: 0.03 MPa;

[0057] Reaction temperature: 170℃;

[0058] Reaction time: 100 hours;

[0059] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0060] Example 2

[0061] 1. Catalyst Preparation

[0062] (1) Take 100g of activated carbon (same as in Example 1) and add it to 200ml of aqueous solution containing hydrochloric acid and acetic acid. Heat it at 90℃ for 2h. The mass fraction of acetic acid in the solution is 9% and the mass fraction of hydrochloric acid is 1%. Then filter, wash with water and dry to obtain carrier 1.

[0063] (2) Take 100g of carrier 1 and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0064] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0065] 2. Catalyst Evaluation

[0066] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0067] Catalyst loading volume: 40 ml;

[0068] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0069] Reactant feed space velocity: 300hr -1 ;

[0070] Reaction pressure: 0.03 MPa;

[0071] Reaction temperature: 170℃;

[0072] Reaction time: 100 hours;

[0073] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0074] Example 3

[0075] 1. Catalyst Preparation

[0076] (1) Take 100g of activated carbon (same as in Example 1) and add it to 200ml of an aqueous solution containing hydrochloric acid and acetic acid. Heat it at 90℃ for 2h. The mass fraction of acetic acid in the solution is 9% and the mass fraction of hydrochloric acid is 1%. Then filter, wash with water and dry to obtain carrier 1.

[0077] (2) Take 100g of carrier 1 and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0078] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11%. Filter and dry to obtain the catalyst.

[0079] 2. Catalyst Evaluation

[0080] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0081] Catalyst loading volume: 40 ml;

[0082] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0083] Reactant feed space velocity: 300hr -1 ;

[0084] Reaction pressure: 0.03 MPa;

[0085] Reaction temperature: 170℃;

[0086] Reaction time: 100 hours;

[0087] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0088] Example 4

[0089] 1. Catalyst Preparation

[0090] (1) Take 100g of activated carbon (same as in Example 1) and add 200ml of an aqueous solution containing acetic acid and hydrochloric acid. Heat at 90℃ for 2h. The mass fraction of acetic acid in the solution is 4% and the mass fraction of hydrochloric acid is 6%. Filter, wash with water and dry to obtain carrier 1.

[0091] (2) Take 100g of carrier 1 and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0092] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0093] 2. Catalyst Evaluation

[0094] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0095] Catalyst loading volume: 40 ml;

[0096] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0097] Reactant feed space velocity: 300hr -1 ;

[0098] Reaction pressure: 0.03 MPa;

[0099] Reaction temperature: 170℃;

[0100] Reaction time: 100 hours;

[0101] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0102] Example 5

[0103] 1. Catalyst Preparation

[0104] (1) Take 100g of activated carbon (same as in Example 1) and add 200ml of aqueous solution containing hydrochloric acid and acetic acid. Heat at 90℃ for 2h. The mass fraction of acetic acid in the solution is 3.5% and the mass fraction of hydrochloric acid is 6.5%. Filter, wash with water and dry to obtain catalyst support i.

[0105] (2) Take 100g of catalyst support i and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0106] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0107] 2. Catalyst Evaluation

[0108] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0109] Catalyst loading volume: 40 ml;

[0110] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0111] Reactant feed space velocity: 300hr -1 ;

[0112] Reaction pressure: 0.03 MPa;

[0113] Reaction temperature: 170℃;

[0114] Reaction time: 100 hours;

[0115] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0116] Comparative Example 1

[0117] 1. Catalyst Preparation

[0118] (1) Take 100g of activated carbon (same as in Example 1) and add 200ml of aqueous solution containing hydrochloric acid. Heat at 90℃ for 2h, wherein the mass fraction of hydrochloric acid in the solution is 10%; filter, wash with water and dry to obtain carrier 1.

[0119] (2) Take 100g of carrier 1 and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0120] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0121] 2. Catalyst Evaluation

[0122] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0123] Catalyst loading volume: 40 ml;

[0124] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0125] Reactant feed space velocity: 300hr -1 ;

[0126] Reaction pressure: 0.03 MPa;

[0127] Reaction temperature: 170℃;

[0128] Reaction time: 100 hours;

[0129] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0130] Comparative Example 2

[0131] 1. Catalyst Preparation

[0132] (1) Take 100g of activated carbon (same as in Example 1) and add 200ml of aqueous solution containing acetic acid. Heat at 90℃ for 2h, wherein the mass fraction of acetic acid in the solution is 10%; filter, wash with water and dry to obtain carrier 1.

[0133] (2) Take 100g of carrier 1 and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0134] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0135] 2. Catalyst Evaluation

[0136] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0137] Catalyst loading volume: 40 ml;

[0138] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0139] Reactant feed space velocity: 300hr -1 ;

[0140] Reaction pressure: 0.03 MPa;

[0141] Reaction temperature: 170℃;

[0142] Reaction time: 100 hours;

[0143] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0144] Comparative Example 3

[0145] 1. Catalyst Preparation

[0146] (1) Take 100g of activated carbon (same as in Example 1) and add 200ml of sulfuric acid-containing aqueous solution. Heat at 90℃ for 2h, wherein the mass fraction of sulfuric acid in the solution is 10%; filter, wash with water and dry to obtain carrier 1.

[0147] (2) Take 100g of carrier 1 and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0148] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0149] 2. Catalyst Evaluation

[0150] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0151] Catalyst loading volume: 40 ml;

[0152] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0153] Reactant feed space velocity: 300hr -1 ;

[0154] Reaction pressure: 0.03 MPa;

[0155] Reaction temperature: 170℃;

[0156] Reaction time: 100 hours;

[0157] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0158] Comparative Example 4

[0159] 1. Catalyst Preparation

[0160] (1) Take 100g of activated carbon (same as in Example 1) and add 200ml of aqueous solution containing nitric acid. Heat at 90℃ for 2h, wherein the mass fraction of nitric acid in the solution is 10%; filter, wash with water and dry to obtain carrier 1.

[0161] (2) Take 100g of catalyst support i and calcine it at 200℃ for 1h under nitrogen atmosphere;

[0162] (3) Take 50g of catalyst support and add it to 100ml of aqueous solution containing zinc acetate and bismuth carbonate. Soak it at 70℃ for 4h. The mass fraction of Zn in the aqueous solution of zinc acetate is 11% and the concentration of bismuth is 10ppmw. Filter and dry to obtain the catalyst.

[0163] 2. Catalyst Evaluation

[0164] The evaluation was conducted using a fixed-bed reactor, under the following conditions:

[0165] Catalyst loading volume: 40 ml;

[0166] Composition of reaction raw materials (in molar ratio): Acetylene: Acetic acid = 5:1;

[0167] Reactant feed space velocity: 300hr -1 ;

[0168] Reaction pressure: 0.03 MPa;

[0169] Reaction temperature: 170℃;

[0170] Reaction time: 100 hours;

[0171] The content of each component in the reaction product was analyzed by gas chromatography, and then the space-time yield of the catalyst was calculated. 10g of catalyst was nitrated with 3ml of nitric acid, and the volume was adjusted to 5ml. The chlorine content in the catalyst was determined and calculated by ion chromatography. The experimental data are listed in Table 1.

[0172] Table 1

[0173]

[0174] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for preparing a catalyst for the acetylene process to produce vinyl acetate, characterized in that, Includes the following steps: (1) The carrier was treated with a mixed solution containing hydrochloric acid and acetic acid, then filtered, washed and dried to obtain carrier 1; (2) Calcine carrier 1 under an inert atmosphere to obtain carrier 2; (3) The support 2 is impregnated with a solution containing zinc acetate and optional co-catalyst, filtered, and dried to obtain the catalyst; The co-catalyst is selected from at least one of Group VA metal element compounds; The catalyst contains 5-100 ppb of chlorine. In step (1), the treatment refers to immersing the carrier in the mixed solution of hydrochloric acid and acetic acid, the treatment temperature is 70-100℃, and the treatment time is 1-4h; The carrier is activated carbon.

2. The preparation method according to claim 1, characterized in that, In step (1), the mass ratio of acetic acid to hydrochloric acid in the mixed solution containing hydrochloric acid and acetic acid is (1:9)-(9:1). And / or the mass content of hydrochloric acid in the mixed solution containing hydrochloric acid and acetic acid is 1%-10%, and / or the mass content of acetic acid in the mixed solution containing hydrochloric acid and acetic acid is 1%-10%; And / or the mass ratio of the carrier to the mixed solution containing hydrochloric acid and acetic acid is 1:(1-5).

3. The preparation method according to claim 2, characterized in that, In step (1), the mass ratio of acetic acid to hydrochloric acid in the mixed solution containing hydrochloric acid and acetic acid is (1:2)-(4:1).

4. The preparation method according to any one of claims 1-3, characterized in that, In step (2), the inert atmosphere is at least one of N2 and Ar; And / or the calcination temperature is 150-450℃; and / or the calcination time is 0.5-4h; And / or in step (3), the immersion temperature is 50-90°C and the immersion time is 1-6h.

5. The preparation method according to claim 4, characterized in that, The calcination temperature is 200-300℃; and / or the calcination time is 1-2 hours.

6. The preparation method according to any one of claims 1-3, characterized in that, The specific surface area of ​​the activated carbon is 800-1400 cm². 2 / g, with an adsorption pore volume of 0.4-0.8cm³. 3 / g.

7. The preparation method according to any one of claims 1-3, characterized in that, The Group VA metal compounds include oxides of Group VA metals, halides of Group VA metals, and / or salts of Group VA metals.

8. The preparation method according to claim 7, characterized in that, The Group VA metal element is bismuth and / or antimony.

9. The preparation method according to claim 8, characterized in that, The Group VA metal element compound is bismuth carbonate and / or basic bismuth carbonate.

10. The preparation method according to any one of claims 1-3, characterized in that, The catalyst contains 5-50 ppb of chlorine.

11. The preparation method according to claim 10, characterized in that, The catalyst contains 25-50 ppb of chlorine.

12. A catalyst for the preparation of vinyl acetate by the acetylene process, prepared by any one of claims 1-11.

13. The catalyst according to claim 12, characterized in that, The catalyst comprises a support and an active component loaded thereon, the active component comprising zinc acetate and optional co-catalyst, the active component being in a weight ratio of 1:(1-5) to the support.

14. The application of the catalyst as described in claim 12 or 13 in the acetylene process for the preparation of vinyl acetate, wherein, The application includes reacting a feed gas containing acetylene and acetic acid in the presence of the catalyst.

15. The application according to claim 14, characterized in that, The raw material gas contains acetylene:acetic acid in a molar ratio of 1:(4-8).

16. The application according to claim 14 or 15, characterized in that, The reaction pressure is 0.01-0.05 MPa; and / or the reaction temperature is 160-200 °C; and / or the volume hourly space velocity of the feed gas is 250-350 hr. -1 .

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