A method for producing acetonitrile by reacting an acetate with ammonia
By preparing a specific catalyst composed of a support and vanadates and alkali metal oxides, the problems of insufficient conversion and selectivity in acetonitrile production were solved, achieving efficient production of acetonitrile and alcohols, which is applicable to the chemical and chemical engineering fields.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DALIAN INSTITUTE OF CHEMICAL PHYSICS CHINESE ACADEMY OF SCIENCES
- Filing Date
- 2024-12-02
- Publication Date
- 2026-06-02
AI Technical Summary
Existing acetonitrile production methods suffer from insufficient conversion and selectivity, especially in the acetate amination process where the selectivity between acetonitrile and alcohols needs improvement, and the high cost limits their industrial application.
Acetonitrile is produced by reacting acetate with ammonia using a catalyst composed of a support and vanadate and alkali metal oxide supported on the surface of the support. The catalyst is prepared by mixing, molding and calcining a specific support composed of vanadate and alkali metal oxide. The reaction conditions are 300-400℃ and 0.1-1MPa.
The conversion rate of acetate reached over 99%, and the selectivity of acetonitrile and alcohols reached over 99.5%. The catalyst preparation is simple and easy to scale up for production, and it is economical.
Abstract
Description
Technical Field
[0001] This application relates to a method for producing acetonitrile by reacting acetate with ammonia, which belongs to the field of chemical engineering. Background Technology
[0002] Acetonitrile is an important organic intermediate and solvent with good solubility, and can be used to prepare a variety of nitrogen-containing compounds.
[0003] Currently, acetonitrile in industry mainly comes from the byproduct of acrylonitrile production. Its output is limited by acrylonitrile production. Besides acrylonitrile, other methods for producing acetonitrile include ethanol ammoniation and acetate ammoniation. However, these methods suffer from drawbacks such as high corrosivity and high cost, and are not yet industrially applied. In addition, acetate ammoniation to acetonitrile is another acetonitrile production method under research. CN113304764 discloses a catalyst for the ammoniation and dehydration of methyl acetate containing phosphate, nitrate, and boride to produce acetonitrile. Currently, the conversion rate and selectivity of acetate ammoniation to acetonitrile need further improvement. Furthermore, since this method produces alcohols as byproducts of acetonitrile production, and these alcohols can be recycled to prepare acetates, the selectivity of alcohols produced as byproducts during acetate ammoniation also needs further improvement. To make acetate ammoniation to acetonitrile more economical and achieve industrial application, improving the acetate conversion rate and the selectivity of acetonitrile and alcohols is crucial. Summary of the Invention
[0004] According to one aspect of this application, a method for producing acetonitrile by reacting acetate with ammonia is provided, comprising the following steps:
[0005] In a reactor, acetate, ammonia, and catalyst are brought into contact and reacted to produce acetonitrile.
[0006] The acetate is selected from at least one of methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and cyclohexyl acetate;
[0007] The catalyst consists of a support and vanadates and alkali metal oxides of active components supported on the surface of the support.
[0008] The vanadate is selected from at least one of bismuth vanadate, silver metavanadate, ammonium metavanadate, lithium vanadate, lithium metavanadate, sodium vanadate, sodium metavanadate, potassium vanadate, and potassium metavanadate.
[0009] The alkali metal oxide is selected from at least one of lithium oxide, sodium oxide, and potassium oxide;
[0010] The carrier is selected from at least one of silica, alumina, and molecular sieve;
[0011] In the catalyst, the mass content of vanadate is 0.1-10 wt%, and the mass content of alkali metal oxide is 0.01-5 wt%.
[0012] The catalyst is obtained through the following steps:
[0013] (1) Mix the support precursor with vanadate and binder, shape it into spheres or strips, dry it for I, calcine it for I, and obtain the catalyst precursor;
[0014] (2) An equal volume of an aqueous solution containing an alkali metal precursor is impregnated onto the catalyst precursor, dried (II), and calcined (II) to obtain the catalyst.
[0015] The carrier precursor is selected from at least one of the following: silica sol, water glass, silica, γ-alumina, boehmite, aluminum isopropoxide, ZSM-5 molecular sieve, ZSM-11 molecular sieve, ZSM-35 molecular sieve, MCM-22 molecular sieve, Beta molecular sieve, and Y-type molecular sieve.
[0016] The binder is a solution of nitric acid and / or hydrochloric acid for aluminum oxide;
[0017] The temperature of the drying process I is 100–140°C;
[0018] The drying time for step I is 8–24 hours;
[0019] The temperature of the calcination I is 300–600°C;
[0020] The roasting time for I is 2 to 24 hours.
[0021] The alkali metal precursor is selected from at least one of lithium nitrate, sodium nitrate, potassium nitrate, lithium chloride, sodium chloride, and potassium chloride.
[0022] The temperature of the drying II process is 100–140°C;
[0023] The drying time for step II is 8–24 hours;
[0024] The temperature of calcination II is 300–600°C;
[0025] The roasting time for the second stage is 2 to 24 hours.
[0026] The reaction temperature is 300–400°C;
[0027] The reaction pressure is 0.1–1 MPa.
[0028] The space velocity of the acetate is 0.1–3 h⁻¹. -1 ;
[0029] The molar ratio of ammonia to acetate is 1 to 40:1.
[0030] The beneficial effects that this application can produce include:
[0031] 1) The catalysts for producing acetonitrile and alcohols provided in this application have suitable active centers and acid properties. In the reaction of acetate with ammonia, the conversion rate of acetate can reach more than 99%, and the selectivity of acetonitrile and alcohols can reach more than 99.5% respectively.
[0032] 2) The catalyst preparation method for producing acetonitrile and alcohols provided in this application is simple, easy to scale up, and has high selectivity for both acetonitrile and alcohols, and is economical. Detailed Implementation
[0033] The present invention will be further described below with reference to embodiments, but this application is not limited to these embodiments. Unless otherwise specified, the raw materials used in the embodiments of this application were all purchased commercially.
[0034] In the embodiments of this application, the conversion rate and selectivity are calculated as follows:
[0035] Conversion rate of acetate = (1 - number of moles of acetate in the product / number of moles of acetate in the raw material) * 100%.
[0036] Selectivity of acetonitrile = (moles of acetonitrile in the product / (moles of acetate in the feed - moles of acetate in the product)) * 100%.
[0037] Alcohol selectivity = (moles of alcohol in product / (moles of acetate in feed - moles of acetate in product)) * 100%.
[0038] Example 1
[0039] 235g of 30% silica sol, 5g of bismuth vanadate, 20g of alumina, and 10g of nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 24 hours, the mixture was calcined at 500℃ for 6 hours to obtain a catalyst precursor. An equal volume of 4.6g of lithium nitrate aqueous solution was impregnated onto the catalyst precursor. After drying at 120℃ for 24 hours, the mixture was calcined at 500℃ for 6 hours to obtain catalyst A. Catalyst A was loaded into a tubular reactor, and methyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 250℃, the pressure was 0.5MPa, and the methyl acetate space velocity was 1 h⁻¹. -1 The molar ratio of ammonia to methyl acetate was 20:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0040] Example 2
[0041] 200g of 35% water glass, 10g of silver metavanadate, 20g of alumina, and 10g of hydrochloric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 12 hours, the mixture was calcined at 600℃ for 2 hours to obtain a catalyst precursor. An equal volume of 0.03g of sodium nitrate aqueous solution was impregnated onto the catalyst precursor. After drying at 120℃ for 12 hours, the mixture was calcined at 600℃ for 2 hours to obtain catalyst B. Catalyst B was loaded into a tubular reactor, and ethyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 200℃, the pressure was 1MPa, and the ethyl acetate space velocity was 0.1 h⁻¹. -1 The molar ratio of ammonia to ethyl acetate was 40:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0042] Example 3
[0043] 78g of silica, 2g of ammonium metavanadate, 20g of alumina, and 10g of hydrochloric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 140℃ for 8 hours, the mixture was calcined at 400℃ for 24 hours to obtain a catalyst precursor. An equal volume of 0.21g of potassium nitrate aqueous solution was impregnated onto the catalyst precursor. After drying at 140℃ for 8 hours, the mixture was calcined at 400℃ for 24 hours to obtain catalyst C. Catalyst C was loaded into a tubular reactor, and propyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 250℃, the pressure was 0.1MPa, and the propyl acetate space velocity was 0.5h⁻¹. -1 The molar ratio of ammonia to propyl acetate was 30:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0044] Example 4
[0045] 76g of γ-alumina, 2g of lithium vanadate, 20g of silicon dioxide, and 10g of nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 130℃ for 12 hours, the mixture was calcined at 300℃ for 24 hours to obtain a catalyst precursor. An equal volume of 1.58g of potassium chloride aqueous solution was impregnated onto the catalyst precursor. After drying at 130℃ for 12 hours, the mixture was calcined at 300℃ for 24 hours to obtain catalyst D. Catalyst D was loaded into a tubular reactor, and butyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 300℃, the pressure was 0.1MPa, and the butyl acetate space velocity was 1 h⁻¹. -1 The molar ratio of ammonia to butyl acetate was 10:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0046] Example 5
[0047] 100g of boehmite, 6g of lithium metavanadate, 20g of silica, and 10g of nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 15 hours, the mixture was calcined at 300℃ for 12 hours to obtain a catalyst precursor. An equal volume of 3.77g of sodium chloride aqueous solution was impregnated onto the catalyst precursor. After drying at 120℃ for 15 hours, the mixture was calcined at 300℃ for 12 hours to obtain catalyst E. Catalyst E was loaded into a tubular reactor, and cyclohexyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 350℃, the pressure was 0.1MPa, and the cyclohexyl acetate space velocity was 2h⁻¹. -1 The molar ratio of ammonia to cyclohexyl acetate was 20:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0048] Example 6
[0049] 470g of aluminum isopropoxide, 6g of sodium vanadate, 20g of silicon dioxide, and 10g of hydrochloric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 8 hours, the mixture was calcined at 450℃ for 16 hours to obtain a catalyst precursor. An equal volume of 7.91g of lithium chloride was prepared as an aqueous solution and impregnated onto the catalyst precursor. After drying at 120℃ for 8 hours, the mixture was calcined at 450℃ for 16 hours to obtain catalyst F. Catalyst F was loaded into a tubular reactor, and methyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 300℃, the pressure was 0.1MPa, and the methyl acetate space velocity was 3h⁻¹. -1 The molar ratio of ammonia to methyl acetate was 30:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0050] Example 7
[0051] 75g ZSM-5, 4g sodium metavanadate, 20g alumina, and 10g nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 8 hours, the mixture was calcined at 550℃ for 8 hours to obtain the catalyst precursor. An equal volume of 1.37g sodium nitrate aqueous solution was prepared and impregnated onto the catalyst precursor. After drying at 120℃ for 8 hours, the mixture was calcined at 550℃ for 8 hours to obtain catalyst G. Catalyst G was loaded into a tubular reactor, and ethyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 280℃, the pressure was 0.1MPa, and the ethyl acetate space velocity was 2h⁻¹. -1 The molar ratio of ammonia to ethyl acetate was 15:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0052] Example 8
[0053] 77g ZSM-11, 0.1g potassium vanadate, 20g alumina, and 10g nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 8 hours, the mixture was calcined at 550℃ for 8 hours to obtain a catalyst precursor. An equal volume of 2.74g sodium nitrate aqueous solution was prepared and impregnated onto the catalyst precursor. After drying at 120℃ for 8 hours, the mixture was calcined at 550℃ for 8 hours to obtain catalyst H. Catalyst H was loaded into a tubular reactor, and propyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 320℃, the pressure was 0.1MPa, and the propyl acetate space velocity was 0.5h⁻¹. -1 The molar ratio of ammonia to propyl acetate was 35:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0054] Example 9
[0055] 78g ZSM-11, 1g potassium metavanadate, 20g alumina, and 10g nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 140℃ for 12 hours, the mixture was calcined at 550℃ for 4 hours to obtain the catalyst precursor. An equal volume of 1.37g sodium nitrate aqueous solution was prepared and impregnated onto the catalyst precursor. After drying at 120℃ for 8 hours, the mixture was calcined at 550℃ for 4 hours to obtain catalyst I. Catalyst I was loaded into a tubular reactor, and butyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 260℃, the pressure was 0.1MPa, and the butyl acetate space velocity was 0.5h⁻¹. -1 The molar ratio of ammonia to butyl acetate was 35:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0056] Example 10
[0057] 78g of MCM-22, 2g of bismuth vanadate, 20g of silicon dioxide, and 10g of nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 12 hours, the mixture was calcined at 550℃ for 6 hours to obtain a catalyst precursor. An equal volume of 0.23g of lithium nitrate was prepared as an aqueous solution and impregnated onto the catalyst precursor. After drying at 120℃ for 12 hours, the mixture was calcined at 550℃ for 6 hours to obtain catalyst J. Catalyst J was loaded into a tubular reactor, and methyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 300℃, the pressure was 0.1MPa, and the methyl acetate space velocity was 0.1h⁻¹. -1 The molar ratio of ammonia to methyl acetate was 1:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0058] Example 11
[0059] 79g Beta, 0.5g lithium vanadate, 20g silicon dioxide, and 10g nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 12 hours, the mixture was calcined at 600℃ for 4 hours to obtain the catalyst precursor. An equal volume of 0.19g sodium chloride aqueous solution was impregnated onto the catalyst precursor. After drying at 120℃ for 12 hours, the mixture was calcined at 600℃ for 4 hours to obtain catalyst K. Catalyst K was loaded into a tubular reactor, and methyl acetate and ammonia gas were introduced to react with the catalyst. The reaction temperature was 350℃, the pressure was 0.1MPa, and the methyl acetate space velocity was 0.5h⁻¹. -1 The molar ratio of ammonia to methyl acetate was 5:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0060] Example 12
[0061] 78g of Y-type molecular sieve, 1g of lithium vanadate, 20g of silica, and 10g of nitric acid were mixed, stirred, kneaded, and shaped into spheres. After drying at 120℃ for 24 hours, the mixture was calcined at 500℃ for 6 hours to obtain a catalyst precursor. An equal volume of 0.79g of potassium chloride aqueous solution was impregnated onto the catalyst precursor. After drying at 120℃ for 24 hours, the mixture was calcined at 500℃ for 6 hours to obtain catalyst L. Catalyst L was loaded into a tubular reactor, and ethyl acetate and ammonia gas were introduced to react with the catalyst at a reaction temperature of 300℃, a pressure of 0.2MPa, and an ethyl acetate space velocity of 1 h⁻¹. -1 The molar ratio of ammonia to ethyl acetate was 20:1. The composition of the reaction products was analyzed by gas chromatography, and the calculated reaction results are listed in Table 1.
[0062] Table 1 Results of acetate amination reaction
[0063] Example Conversion rate % Acetonitrile selectivity % Alcohol selectivity % 1 99.1 99.6 99.7 2 99.4 99.6 99.6 3 99.6 99.7 99.8 4 99.0 99.6 99.9 5 99.5 99.9 99.8 6 99.2 99.8 99.9 7 99.7 99.7 99.8 8 99.4 99.6 99.7 9 99.7 99.8 99.6 10 99.3 99.7 99.8 11 99.1 99.6 99.7 12 99.5 99.7 99.9
[0064] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A method for producing acetonitrile by reacting acetate with ammonia, characterized in that, Includes the following steps: In a reactor, acetate, ammonia, and catalyst are brought into contact and reacted to produce acetonitrile. The acetate is selected from at least one of methyl acetate, ethyl acetate, propyl acetate, butyl acetate, and cyclohexyl acetate; The catalyst consists of a support and vanadates and alkali metal oxides of active components supported on the surface of the support. The vanadate is selected from at least one of bismuth vanadate, silver metavanadate, ammonium metavanadate, lithium vanadate, lithium metavanadate, sodium vanadate, sodium metavanadate, potassium vanadate, and potassium metavanadate. The alkali metal oxide is selected from at least one of lithium oxide, sodium oxide, and potassium oxide; The carrier is selected from at least one of silica, alumina, and molecular sieve; In the catalyst, the mass content of vanadate is 0.1-10 wt%, and the mass content of alkali metal oxide is 0.01-5 wt%.
2. The method according to claim 1, characterized in that, The catalyst is obtained through the following steps: (1) Mix the support precursor with vanadate and binder, shape it into spheres or strips, dry it for I, calcine it for I, and obtain the catalyst precursor; (2) An equal volume of an aqueous solution containing an alkali metal precursor is impregnated onto the catalyst precursor, dried (II), and calcined (II) to obtain the catalyst.
3. The method according to claim 2, characterized in that, The carrier precursor is selected from at least one of the following: silica sol, water glass, silica, γ-alumina, boehmite, aluminum isopropoxide, ZSM-5 molecular sieve, ZSM-11 molecular sieve, ZSM-35 molecular sieve, MCM-22 molecular sieve, Beta molecular sieve, and Y-type molecular sieve. The binder is a solution of nitric acid and / or hydrochloric acid for aluminum oxide; The temperature of the drying process is 100–140°C. The drying time for step I is 8–24 hours; The temperature of the calcination I is 300–600°C; The roasting time for I is 2 to 24 hours.
4. The method according to claim 2, characterized in that, The alkali metal precursor is selected from at least one of lithium nitrate, sodium nitrate, potassium nitrate, lithium chloride, sodium chloride, and potassium chloride. The temperature of the drying II process is 100–140°C; The drying time for step II is 8–24 hours; The temperature of calcination II is 300–600°C; The roasting time for the second stage is 2 to 24 hours.
5. The method according to claim 1, characterized in that, The reaction temperature is 300–400°C; The reaction pressure is 0.1–1 MPa.
6. The method according to claim 2, characterized in that, The space velocity of the acetate is 0.1–3 h⁻¹. -1 ; The molar ratio of ammonia to acetate is 1 to 40:1.