A catalyst for catalytic oxidation reactions and its applications

Abstract

This invention provides a catalyst for catalytic oxidation reactions and its application. The catalyst comprises the following components: cobalt; iron; and yttrium. The catalyst provided by this invention can be used for the oxidation of cyclohexane and can generate glutaric acid with high selectivity, reaching over 70% and a yield of over 50%.

Description

Technical Field

[0001] This invention belongs to the field of catalysts, specifically relating to a catalyst for catalytic oxidation reactions and its applications. Background Technology

[0002] The normal oxidation and ring-opening of C6 cycloalkanes yields C6 adipic acid, with a small amount of glutaric acid as a byproduct. For example, current technologies commonly use cobalt, manganese, and copper as catalysts to primarily produce adipic acid, with glutaric acid accounting for only 5% of the product.

[0003] Existing methods for preparing glutaric acid include extracting small amounts from the byproducts of cyclohexane oxidation to adipic acid. However, this method yields low-cost glutaric acid, resulting in a high price and limiting its application. Alternatively, glutaric acid can be prepared by oxidizing C5 cyclopentanone (which is expensive) or by oxidizing cyclopentane with sodium hypochlorite catalyzed by ruthenium trichloride. However, both methods involve high raw material costs, impacting the economic viability of these processes. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a catalyst for catalytic oxidation reactions and its application, which can selectively catalytically oxidize cyclohexane to obtain glutaric acid as the main product, thereby reducing the production cost of glutaric acid.

[0005] In a first aspect, the present invention provides a catalyst for catalytic oxidation reactions, comprising: cobalt; iron and yttrium.

[0006] In some embodiments, the cobalt element is in the form of a cobalt salt or cobalt oxide.

[0007] In some embodiments, the iron element is in the form of an iron salt or an iron oxide.

[0008] In some embodiments, the yttrium element is in the form of a yttrium salt or yttrium oxide.

[0009] In some embodiments, the mass ratio of cobalt to iron is 1:(0.5 to 10), for example, 1:0.5, 1:0.7, 1:1, 1:1.2, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10.

[0010] In some embodiments, the mass ratio of cobalt to iron is 1:(1-5).

[0011] In some embodiments, the mass ratio of cobalt to iron is 1:(1-3).

[0012] In some embodiments, the mass ratio of cobalt to yttrium is 1:(0.2 to 5), for example 1:0.2, 1:0.5, 1:0.8, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5.

[0013] In some embodiments, the mass ratio of cobalt to yttrium is 1:(0.5-3).

[0014] In some embodiments, the mass ratio of cobalt to yttrium is 1:(0.5 to 2).

[0015] In some embodiments, the mass ratio of yttrium to iron is 1:(0.5 to 5); for example, 1:0.5, 1:0.8, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5.

[0016] In some embodiments, the mass ratio of yttrium to iron is 1:(1-3).

[0017] In some embodiments, the mass ratio of yttrium to iron is 1:(1-2).

[0018] In some embodiments, the iron salt is selected from any one or more of acetate, nitrate, sulfate, carbonate, or hydrochloride.

[0019] In some embodiments, the yttrium salt is selected from any one or more of acetate, nitrate, sulfate, carbonate, or hydrochloride.

[0020] In some embodiments, the cobalt salt is selected from any one or more of acetate, nitrate, sulfate, carbonate, or hydrochloride.

[0021] Considering the solubility of iron salts, yttrium salts, and cobalt salts, and the corrosive effects of halogens on equipment, in some embodiments, the iron salts, yttrium salts, and cobalt salts are each independently selected from one or more of acetates, nitrates, and sulfates.

[0022] In a second aspect, the present invention provides a method for preparing the catalyst described in the first aspect of the present invention, the method comprising mixing cobalt salt, yttrium salt and iron salt.

[0023] In a third aspect, the present invention provides the application of the catalyst described in the first aspect of the present invention in the reaction of cyclohexane to prepare glutaric acid.

[0024] In some embodiments, the reaction for preparing glutaric acid from cyclohexane includes: reacting cyclohexane with an oxygen-containing gas in the presence of a catalyst and a solvent to produce glutaric acid.

[0025] In some embodiments, the reaction for preparing glutaric acid from cyclohexane includes:

[0026] (1) Add the catalyst, solvent, and cyclohexane to the oxidation reactor to form a reaction mixture;

[0027] (2) Introduce oxygen-containing gas into the reactor and heat the reactor to the reaction temperature and reaction pressure;

[0028] (3) Oxygen-containing gas under working pressure is continuously fed into the reactor for contact;

[0029] (4) Stop feeding and end the reaction.

[0030] In some embodiments, the solvent is selected from one or more of acetic acid, acetonitrile, ethyl acetate, chlorobenzene, or methyl acetate.

[0031] In some embodiments, the solvent is acetic acid.

[0032] The catalyst provided by this invention can be used for the oxidation reaction of cyclohexane and can generate glutaric acid with high selectivity, with a selectivity of over 70% and a yield of over 50%. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention in any way. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of this disclosure. Such structures and techniques have also been described in many publications.

[0034] 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.

[0035] The present invention will be described in detail below through embodiments.

[0036] In the method of this invention, the selectivity of glutaric acid is calculated as follows: glutaric acid selectivity = molar amount of glutaric acid produced in the reaction / molar amount of cyclohexane consumed in the reaction * 100%.

[0037] The yield of glutaric acid is calculated as follows:

[0038] Glutaric acid yield = (molar amount of glutaric acid produced in the reaction) / (molar amount of cyclohexane in the feed) * 100%.

[0039] The reagents used in the following examples are commercially available and of analytical grade.

[0040] Example 1

[0041] 1) Take 0.15g of catalyst, which includes cobalt acetate, yttrium acetate, and iron acetate. The mass ratio of cobalt:yttrium:iron is 8:9:14. Dissolve the catalyst in 100g of acetic acid and add 15g of cyclohexane as a reaction raw material. Mix the above materials to prepare an acetic acid solution and add it to the oxidation reactor.

[0042] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0043] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0044] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 63.1%, and the selectivity of glutaric acid was 83.5%.

[0045] Example 2

[0046] 1) Take 0.15g of catalyst, which includes cobalt acetate, yttrium acetate, and iron acetate, wherein the mass ratio of cobalt:yttrium:iron is 10:9:14. Dissolve the above catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0047] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0048] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0049] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 65.7%, and the selectivity of glutaric acid was 76.8%.

[0050] Example 3

[0051] 1) Take 0.15g of catalyst, which includes cobalt acetate, yttrium acetate, and iron acetate. The mass ratio of cobalt:yttrium:iron is 8:12:14. Dissolve the catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0052] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0053] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0054] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 63.3%, and the selectivity of glutaric acid was 82.9%.

[0055] Example 4

[0056] 1) Take 0.15g of catalyst, which includes cobalt acetate, yttrium acetate, and iron acetate. The mass ratio of cobalt:yttrium:iron is 8:9:18. Dissolve the catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0057] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0058] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0059] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 62.7%, and the selectivity of glutaric acid was 83.6%.

[0060] Comparative Example 1

[0061] 1) Take 0.15g of catalyst, which includes cobalt acetate and yttrium acetate, wherein the mass ratio of cobalt to yttrium is 15:16. Dissolve the catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0062] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0063] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0064] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 25.9%, and the selectivity of glutaric acid was 43.7%.

[0065] Comparative Example 2

[0066] 1) Take 0.15g of catalyst, which includes cobalt acetate and iron acetate, wherein the mass ratio of cobalt to iron is 12:19. Dissolve the catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0067] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0068] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0069] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 28.4%, and the selectivity of glutaric acid was 42.8%.

[0070] Comparative Example 3

[0071] 1) Take 0.15g of catalyst, which includes yttrium acetate and iron acetate, wherein the mass ratio of yttrium to iron is 13:18. Dissolve the catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0072] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0073] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0074] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 2.1%, and the selectivity of glutaric acid was 3.5%.

[0075] Comparative Example 4

[0076] 1) Take 0.15g of catalyst, including cobalt acetate, manganese acetate and copper acetate, wherein the mass ratio of cobalt:manganese:copper is 14:2:3. Dissolve the catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, mix the above materials to prepare an acetic acid solution and add it to the oxidation reactor;

[0077] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0078] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0079] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 7.3%, and the selectivity of glutaric acid was 6.9%.

[0080] Comparative Example 5

[0081] 1) Take 0.15g of catalyst, which includes cobalt acetate, copper acetate, and iron acetate. The mass ratio of cobalt:copper:iron is 8:9:14. Dissolve the catalyst in 100g of acetic acid and add 15g of cyclohexane as a reaction raw material. Mix the above materials to prepare an acetic acid solution and add it to the oxidation reactor.

[0082] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0083] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0084] 4) After 4 hours of reaction, stop feeding to end the reaction. Take a sample of the cyclohexane oxidation liquid from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 8.7%, and the selectivity of glutaric acid was 7.9%.

[0085] Comparative Example 6

[0086] 1) Take 0.15g of catalyst, which includes cobalt acetate, manganese acetate, and iron acetate. The mass ratio of cobalt:manganese:iron is 8:9:14. Dissolve the catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0087] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0088] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0089] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 17.7%, and the selectivity of glutaric acid was 19.3%.

[0090] Comparative Example 7

[0091] 1) Take 0.15g of catalyst, which includes cobalt acetate, yttrium acetate, and copper acetate, wherein the mass ratio of cobalt:yttrium:copper is 8:9:14 by elemental mass. Dissolve the above catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0092] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0093] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0094] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 20.6%, and the selectivity of glutaric acid was 18.5%.

[0095] Comparative Example 8

[0096] 1) Take 0.15g of catalyst, which includes cobalt acetate, yttrium acetate, and manganese acetate, wherein the mass ratio of cobalt:yttrium:manganese is 8:9:14 by elemental mass. Dissolve the above catalyst in 100g of acetic acid, add 15g of cyclohexane as a reaction raw material, and mix the above materials to prepare an acetic acid solution, which is then added to the oxidation reactor.

[0097] 2) Oxygen-containing gas (35% oxygen by volume, the remainder being nitrogen) is continuously introduced into the oxidation reactor at a flow rate of 20 g / h. The reactor is heated to a reaction temperature of 140°C and a reaction pressure of 4.0 MPa.

[0098] 3) Acetic acid solution and oxygen-containing gas are continuously fed into the reactor. The feed flow rate of acetic acid solution is 1 g / h (calculated based on the amount of acetic acid in the solution), and the flow rate of oxygen-containing gas is 20 g / h.

[0099] 4) After 4 hours of reaction, the feed was stopped and the reaction was terminated. A sample of the cyclohexane oxidation liquid was taken from the synthesis liquid collection tank for analysis of its composition. The yield of glutaric acid was calculated to be 15.3%, and the selectivity of glutaric acid was 17.9%.

[0100] Table 1

[0101]

[0102]

[0103] As can be seen from Table 1, the catalyst ratio plays an important role in the yield and selectivity of glutaric acid.

[0104] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A catalyst for catalytic oxidation reactions, comprising: cobalt; iron and yttrium; wherein the cobalt is a cobalt salt, the iron is an iron salt, and the yttrium is a yttrium salt; wherein the iron salt, yttrium salt, and cobalt salt are each independently selected from acetates; The mass ratio of cobalt to iron is 1:(0.5~10); The mass ratio of cobalt to yttrium is 1:(0.2~5); The mass ratio of yttrium to iron is 1:(0.5~5).

2. The catalyst according to claim 1, characterized in that, The mass ratio of cobalt to iron is 1:(1~5).

3. The catalyst according to claim 1, characterized in that, The mass ratio of cobalt to iron is 1:(1~3).

4. The catalyst according to claim 1, characterized in that, The mass ratio of cobalt to yttrium is 1:(0.5~3).

5. The catalyst according to claim 1, characterized in that, The mass ratio of cobalt to yttrium is 1:(0.5~2).

6. The catalyst according to claim 1, characterized in that, The mass ratio of yttrium to iron is 1:(1~3).

7. The catalyst according to claim 1, characterized in that, The mass ratio of yttrium to iron is 1:(1~2).

8. The use of any one of the catalysts according to claims 1 to 7 in the reaction of cyclohexane to prepare glutaric acid.

9. The application according to claim 8, characterized in that, The reaction for preparing glutaric acid from cyclohexane includes: reacting cyclohexane with an oxygen-containing gas in the presence of the catalyst and solvent to produce glutaric acid.

10. The application according to claim 9, characterized in that, The solvent is selected from one or more of acetic acid, acetonitrile, ethyl acetate, chlorobenzene, or methyl acetate.

11. The application according to claim 10, characterized in that, The solvent is acetic acid.

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