Catalyst for liquid phase hydrogenation of maleic anhydride to succinic anhydride, preparation method and application thereof

Abstract

The application discloses a catalyst for preparing succinic anhydride through liquid-phase hydrogenation of maleic anhydride, a preparation method and application. The catalyst for preparing succinic anhydride through liquid-phase hydrogenation of maleic anhydride comprises a carrier and an active component supported on the carrier; the active component comprises Ni and Co. The preparation method of the catalyst is as follows: metal salts and ligands of the active component are dissolved in water, the carrier is added to obtain a suspension; the suspension is dried to obtain a precursor of the catalyst; the precursor of the catalyst is calcined in an inert atmosphere to obtain an oxide precursor of the catalyst; and the oxide precursor of the catalyst is subjected to reduction treatment to obtain the catalyst. The catalyst has the advantages of high catalytic activity, high selectivity, simple preparation process and low price, and has the potential for industrial application.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts, and more particularly to a catalyst for preparing succinic anhydride by liquid-phase hydrogenation of maleic anhydride, and a preparation method and application thereof. Background Art

[0002] Maleic anhydride is a commonly used and important basic organic chemical raw material. The C=C double bond in its molecule can be selectively hydrogenated to synthesize succinic anhydride. Succinic anhydride has a wide range of applications in food, surfactants, coatings, pharmaceuticals, agriculture, plastics, and other fields. Importantly, with the development of the biodegradable material polybutylene succinate (PBDS), the market demand for succinic acid, its hydrolysis product, has been growing annually. Therefore, the synthesis of succinic anhydride from maleic anhydride via selective C=C hydrogenation has important implications for the development of petrochemicals and materials science.

[0003] The catalyst system involved in the synthesis of succinic anhydride as raw material comprises noble metal catalyst and non-noble metal catalyst.Wherein, my country's patent CN107473954A and CN102311332A, have selected the noble metals such as Pd, Pt as main active component, and the consumption of noble metal has accounted for the 3.0-10.0wt% of catalyst gross weight.Although good activity and higher selectivity are arranged for hydrogenation reaction, production cost has also increased greatly, and is difficult to realize large-scale industrialization.On the other hand, for non-noble metal catalyst system, nickel is often selected as main active component, although compared to noble metal catalyst, stronger cost advantage is arranged, but also there are some drawbacks in application.As patent CN109529850A discloses a kind of SiO2 load Ni maleic anhydride hydrogenation catalyst preparation method and application thereof, the pressure higher (5.0MPa) that this catalyst is used for liquid phase hydrogenation reaction, and can only be used for batch building-up reactions, can't be applied to continuous large-scale production. Summary of the Invention

[0004] To address the problems encountered in the prior art, the present invention provides a catalyst for the liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride, as well as a preparation method and application thereof. The catalyst of the present invention exhibits high catalytic activity, high selectivity, a simple preparation process, and a low cost, and has potential for industrial application.

[0005] One of the purposes of the present invention is to provide a catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride, the catalyst comprising a carrier and an active component supported on the carrier;

[0006] The active components include Ni and Co;

[0007] Based on the total weight of the catalyst as 100%, the loading amount of the active component is 10-40wt%, for example, it can be 10wt%, 15wt%, 18wt%, 20wt%, 22wt%, 25wt%, 28wt%, 30wt%, 32wt%, 35wt%, 38wt%, 40wt%, and any range between any two values; preferably 15-25wt%, more preferably 18-25wt%.

[0008] In the present invention, the catalyst may also be added with other conventional active metal elements as needed.

[0009] Preferably,

[0010] In the active component, the molar ratio of Ni to Co is 1-10:1, for example, it can be 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, and any range between any two values; preferably, it is 4-6:1.

[0011] Preferably,

[0012] The carrier is an all-silica mesoporous molecular sieve; preferably, the pore size of the all-silica mesoporous molecular sieve is in the range of 2-50 nm, more preferably 6-11 nm.

[0013] In the present invention, the all-silica mesoporous molecular sieve refers to a mesoporous molecular sieve composed entirely of silicon dioxide. Preferably, the all-silica mesoporous molecular sieve carrier is one of SBA-12, SBA-15, MCM-41, MCM-48 or KIT-6; more preferably SBA-15.

[0014] Preferably,

[0015] The specific surface area of ​​the catalyst is 120-570m 2 / g, average pore volume is 0.4-1.0m 3 / g, and the average pore size is 5.9-7.8nm.

[0016] A second object of the present invention is to provide a method for preparing the catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride as described in one of the objects of the present invention, the method comprising the steps of:

[0017] (1) After dissolving the metal salt and ligand of the active component in water, a carrier is added to obtain a suspension;

[0018] (2) drying the suspension to obtain a catalyst precursor;

[0019] (3) calcining the catalyst precursor under an inert atmosphere to obtain an oxide precursor of the catalyst;

[0020] (4) The catalyst is obtained by subjecting the oxide precursor of the catalyst to a reduction treatment.

[0021] Preferably,

[0022] In step (1),

[0023] The metal salt of the active component includes a soluble nickel salt and a soluble cobalt salt; and / or,

[0024] The ligand is selected from carboxyl multidentate ligands, preferably the carboxyl multidentate ligand is citric acid; and / or,

[0025] The mass ratio of the metal salt, ligand and carrier of the active component is 1-4:0.4-8:1; and / or,

[0026] The mass ratio of the water to the carrier is 1-6:1.

[0027] Preferably,

[0028] The soluble nickel salt is selected from at least one of nickel nitrate, nickel sulfate, nickel chloride, basic nickel carbonate or nickel acetate; and / or,

[0029] The soluble cobalt salt is selected from at least one of cobalt nitrate, cobalt sulfate, cobalt chloride or cobalt acetate; and / or,

[0030] The molar ratio of the soluble nickel salt to the soluble cobalt salt is 1-10:1, preferably 4-6:1.

[0031] Preferably,

[0032] In the present invention, the drying in step (2) can be carried out under conventional drying conditions, preferably at a drying temperature of 100-140° C. and a drying time of 36-60 h.

[0033] Preferably,

[0034] In step (3),

[0035] The calcination temperature is 200-600°C and the calcination time is 3-5h; and / or,

[0036] In step (4),

[0037] The reduction treatment conditions are: under hydrogen atmosphere, reduction temperature is 300-700° C., and time is 4-6 hours.

[0038] The third object of the present invention is to provide the use of the catalyst for liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride as described in one of the objects of the present invention in the reaction of liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride.

[0039] In the application of the present invention, the catalyst, hydrogen and maleic anhydride solution are contacted to react to prepare succinic anhydride;

[0040] The temperature of the contact reaction is 50-70°C, for example, 50°C, 55°C, 60°C, 65°C, 70°C, and any range between any two values.

[0041] The pressure of the contact reaction is 1-5 MPa, for example, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa, 3 MPa, 3.5 MPa, 4 MPa, 4.5 MPa, 5 MPa, and any range between any two values; preferably 1-3 MPa, more preferably 1-2 MPa.

[0042] In the present invention, succinic anhydride can be prepared using conventional process conditions. Preferably, the catalyst and maleic anhydride solution are added simultaneously to a slurry bed or suspension bed reactor for reaction. The maleic anhydride solution is a solution of maleic anhydride dissolved in an organic solvent. Preferably, the organic solvent is selected from at least one of tetrahydrofuran, 1,4-dioxane, or γ-butyrolactone.

[0043] The concentration of the maleic anhydride solution is 10 to 30 wt%; and / or,

[0044] The mass ratio of the catalyst to maleic anhydride is 0.01 to 0.05:1; and / or,

[0045] The contact reaction time is 1 to 6 hours.

[0046] Compared with the prior art, the present invention has at least the following advantages:

[0047] 1. The active components of the catalyst of the present invention include Ni and Co, and the catalytic effect of the catalyst is further improved by the special ratio of these two components.

[0048] 2. The active components Ni and Co used in the catalyst of the present invention are inexpensive and have a simple preparation process, which is conducive to industrial application.

[0049] 3. The catalyst of the present invention has a high maleic anhydride conversion rate and succinic anhydride selectivity.

[0050] 4. The catalyst of the present invention reduces the temperature and pressure of the hydrogenation reaction, thereby reducing production costs.

[0051] 5. The present invention adds a carboxyl multidentate ligand during catalyst preparation to improve the dispersion of the active metal; it can also form a carbon-coated metal after calcination to improve the stability of the active metal, thereby improving the performance of the catalyst. DETAILED DESCRIPTION

[0052] The present invention will be described in detail below with reference to specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and are not to be construed as limiting the scope of protection of the present invention. Non-essential improvements and adjustments made by those skilled in the art to the present invention based on the contents of the present invention still fall within the scope of protection of the present invention.

[0053] The raw materials used in the following examples and comparative examples are all commercially available.

[0054] The specific surface area, average pore volume and average pore diameter of the catalyst in the present invention are measured using a multi-point BET method.

[0055] Example 1

[0056] This example is used to illustrate the catalyst for liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride, its preparation method, and the method for producing succinic anhydride of the present invention.

[0057] Weigh 29 g of nickel nitrate (Ni(NO3)2·6H2O), 5.8 g of cobalt nitrate (Co(NO3)2·6H2O), and 22.99 g of citric acid and dissolve them in 40 mL of deionized water (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 1:1) to obtain a Ni-Co mixed solution; weigh 28.90 g of an all-silica mesoporous molecular sieve carrier SBA-15 with a pore size range of 6-11 nm and mix it evenly with the Ni-Co mixed solution to obtain a suspension.

[0058] Then, the mixture was dried at 120° C. for 24 h to obtain a catalyst precursor.

[0059] The precursor is then placed in a muffle furnace and calcined at 400° C. for 4 h in a nitrogen atmosphere to obtain an oxide precursor of the catalyst.

[0060] Finally, the oxide precursor is placed in a hydrogen atmosphere and reduced at 500° C. for 5 hours under normal pressure to obtain a finished catalyst.

[0061] Based on the total weight of the catalyst, the total loading of Ni-Co bimetallic is 19.5 wt% and the specific surface area is 534.16 m 2 / g, and the average pore volume is 0.917m 3 / g, and the average pore diameter is 6.382nm.

[0062] After the catalyst was prepared, its activity was evaluated using the following method: 1.2 g of the catalyst and 500 g of a tetrahydrofuran solution containing 20 wt% maleic anhydride were simultaneously added to a slurry bed reactor. Under the conditions of a reaction temperature of 55° C., a reaction pressure of 2.0 MPa, and a reaction time of 2 hours, the conversion of maleic anhydride and the selectivity for succinic anhydride are shown in Table 1.

[0063] Example 2

[0064] Example 2 uses a method similar to Example 1 to prepare a catalyst, except that the amount of the raw materials used is different. The rest is the same as Example 1, and catalyst S2 is prepared.

[0065] The raw materials used in Example 2 are 29 g of nickel nitrate (Ni(NO3)2·6H2O), 5.8 g of cobalt nitrate (Co(NO3)2·6H2O), and 11.50 g of citric acid (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 2:1), and 1.07 g of SBA-152, an all-silica mesoporous molecular sieve carrier with a pore size range of 6-11 nm, is weighed.

[0066] Based on the total weight of the catalyst S2, the total loading of Ni-Co bimetallic in the catalyst S2 is 25wt%; the specific surface area is 519.37m 2 / g, and the average pore volume is 0.877m 3 / g, average pore size 6.741nm

[0067] After the catalyst was prepared, succinic anhydride was prepared using the same method as in Example 1. The conversion rate of maleic anhydride and the selectivity of succinic anhydride are shown in Table 1.

[0068] Example 3

[0069] Example 3 uses a method similar to Example 1 to prepare a catalyst, except that the amount of the raw materials used is different. The rest is the same as Example 1, and catalyst S3 is prepared.

[0070] The raw materials used in Example 3 are 29 g of nickel nitrate (Ni(NO3)2·6H2O), 5.8 g of cobalt nitrate (Co(NO3)2·6H2O), and 5.75 g of citric acid (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 4:1), and 39.78 g of SBA-15, an all-silica mesoporous molecular sieve carrier with a pore size range of 6-11 nm, is weighed.

[0071] Based on the total weight of the catalyst S3, the total loading of Ni-Co bimetallic in the catalyst S3 is 15wt%; the specific surface area is 498.20m 2 / g, and the average pore volume is 0.824m 3 / g, average pore size 6.639nm

[0072] After the catalyst was prepared, succinic anhydride was prepared using the same method as in Example 1. The conversion rate of maleic anhydride and the selectivity of succinic anhydride are shown in Table 1.

[0073] Example 4

[0074] Example 4 uses a method similar to Example 1 to prepare a catalyst, except that the amount of the raw materials used is different. The rest is the same as Example 1, and catalyst S4 is prepared.

[0075] In Example 4, the raw materials used are 29 g of nickel nitrate (Ni(NO3)2·6H2O), 5.8 g of cobalt nitrate (Co(NO3)2·6H2O), and 45.98 g of citric acid (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 1:2), and 3.18 g of SBA-156, an all-silica mesoporous molecular sieve carrier with a pore size range of 6-11 nm, is weighed.

[0076] Based on the total weight of the catalyst S4, the total loading of Ni-Co bimetallic in the catalyst S4 is 10 wt%; the specific surface area is 454.39 m 2 / g, and the average pore volume is 0.793m 3 / g, and the average pore diameter is 6.821nm.

[0077] After the catalyst was prepared, succinic anhydride was prepared using the same method as in Example 1. The conversion rate of maleic anhydride and the selectivity of succinic anhydride are shown in Table 1.

[0078] Example 5

[0079] Example 5: A catalyst was prepared using a method similar to that of Example 1, except that the amounts of the raw materials used were different. The rest were the same as in Example 1, and catalyst S5 was prepared.

[0080] The raw materials used in Example 5 are 29 g of nickel nitrate (Ni(NO3)2·6H2O), 5.8 g of cobalt nitrate (Co(NO3)2·6H2O), and 68.97 g of citric acid (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 1:3), and 10.53 g of SBA-15, an all-silica mesoporous molecular sieve carrier with a pore size range of 6-11 nm, is weighed.

[0081] Based on the total weight of the catalyst S5, the total loading of Ni-Co bimetallic in the catalyst S5 is 40 wt%. The specific surface area is 441.46 m 2 / g, and the average pore volume is 0.740m 3 / g, and the average pore diameter is 7.083nm.

[0082] After the catalyst was prepared, succinic anhydride was prepared using the same method as in Example 1. The conversion rate of maleic anhydride and the selectivity of succinic anhydride are shown in Table 1.

[0083] Example 6

[0084] This example is used to illustrate the catalyst for liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride, its preparation method, and the method for producing succinic anhydride of the present invention.

[0085] Weigh 29 g of nickel nitrate (Ni(NO3)2·6H2O), 5.8 g of cobalt nitrate (Co(NO3)2·6H2O), and 34.49 g of citric acid and dissolve them in 40 mL of deionized water (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 1:1.5) to obtain a Ni-Co mixed solution; weigh 3.50 g of an all-silica mesoporous molecular sieve carrier SBA-152 with a pore size range of 6-11 nm and mix it evenly with the Ni-Co mixed solution to obtain a suspension.

[0086] Then, the mixture was dried at 120° C. for 24 h to obtain a catalyst precursor.

[0087] The precursor is then placed in a muffle furnace and calcined at 400° C. for 4 h in a nitrogen atmosphere to obtain an oxide precursor of the catalyst.

[0088] Finally, the oxide precursor is placed in a hydrogen atmosphere and reduced at 500° C. for 5 hours under normal pressure to obtain a finished catalyst.

[0089] Based on the total weight of the catalyst S6, the total loading of Ni-Co bimetallic in the catalyst S6 is 23 wt%; the specific surface area is 527.89 m 2 / g, and the average pore volume is 0.899m 3 / g, and the average pore diameter is 6.458nm.

[0090] After the catalyst was prepared, its activity was evaluated using the following method: 1.2 g of the catalyst and 500 g of a tetrahydrofuran solution containing 20 wt% maleic anhydride were simultaneously added to a slurry bed reactor. Under the conditions of a reaction temperature of 75° C., a reaction pressure of 2.0 MPa, and a reaction time of 2 hours, the conversion of maleic anhydride and the selectivity for succinic anhydride are shown in Table 1.

[0091] Comparative Example 1

[0092] This comparative example is used to illustrate a reference catalyst for liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride, a preparation method thereof, and a method for producing succinic anhydride.

[0093] Weigh 29 g of nickel nitrate (Ni(NO3)2·6H2O) and 5.8 g of cobalt nitrate (Co(NO3)2·6H2O) and dissolve them in 40 mL of deionized water to obtain a Ni-Co mixed solution; weigh 0.26 g of an all-silica mesoporous molecular sieve carrier SBA-152 with a pore size range of 6-11 nm and mix it evenly with the Ni-Co mixed solution to obtain a suspension.

[0094] Then, the mixture was dried at 120° C. for 24 h to obtain a catalyst precursor.

[0095] The precursor is then placed in a muffle furnace and calcined at 400° C. for 4 h in a nitrogen atmosphere to obtain an oxide precursor of the catalyst.

[0096] Finally, the oxide precursor was reduced under a hydrogen atmosphere at 500°C for 5 hours at normal pressure to obtain a finished catalyst. The total loading of the Ni-Co bimetallic was 23 wt% based on the total weight of the catalyst.

[0097] After the catalyst was prepared, its activity was evaluated using the following method: 1.2 g of the catalyst and 500 g of a tetrahydrofuran solution containing 20 wt% maleic anhydride were simultaneously added to a slurry bed reactor. Under the conditions of a reaction temperature of 75° C., a reaction pressure of 2.0 MPa, and a reaction time of 2 hours, the conversion of maleic anhydride and the selectivity for succinic anhydride are shown in Table 1.

[0098] Comparative Example 2

[0099] This comparative example is used to illustrate a reference catalyst for liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride, a preparation method thereof, and a method for producing succinic anhydride.

[0100] Weigh 29 g of nickel nitrate (Ni(NO3)2·6H2O) and 19.16 g of citric acid and dissolve them in 40 mL of deionized water (the molar ratio of Ni(NO3)2·6H2O to citric acid is 1:1) to obtain a Ni mixed solution; weigh 19.42 g of an all-silica mesoporous molecular sieve carrier SBA-15 with a pore size range of 6-11 nm and mix it evenly with the Ni mixed solution to obtain a suspension.

[0101] Then, the mixture was dried at 120° C. for 24 h to obtain a catalyst precursor.

[0102] The precursor is then placed in a muffle furnace and calcined at 400° C. for 4 h in a nitrogen atmosphere to obtain an oxide precursor of the catalyst.

[0103] Finally, the oxide precursor was reduced under a hydrogen atmosphere at 500°C for 5 hours at normal pressure to obtain a finished catalyst. The total Ni loading was 23 wt% based on the total weight of the catalyst.

[0104] After the catalyst was prepared, its activity was evaluated using the following method: 1.2 g of the catalyst and 500 g of a tetrahydrofuran solution containing 20 wt% maleic anhydride were simultaneously added to a slurry bed reactor. Under the conditions of a reaction temperature of 75° C., a reaction pressure of 2.0 MPa, and a reaction time of 2 hours, the conversion of maleic anhydride and the selectivity for succinic anhydride are shown in Table 1.

[0105] Table 1 Catalyst performance comparison

[0106] catalyst Maleic anhydride conversion rate (%) Succinic anhydride selectivity (%) Example 1 100.0 99.4 Example 2 100.0 97.4 Example 3 99.8 96.2 Example 4 99.4 94.6 Example 5 98.8 92.1 Example 6 100.0 98.8 Comparative Example 1 96.7 93.2 Comparative Example 2 96.4 91.9

[0107] As can be seen from Table 1, the Ni-Co element-containing catalyst prepared in the embodiment of the present invention has higher activity and selectivity than the catalyst prepared in the comparative example. Specifically:

[0108] It can be seen from Example 1 and Comparative Example 1 that since the hydroxy multidentate ligand citric acid described in the present invention is not introduced in Comparative Example 1, under the same reaction conditions as the present invention, the selectivity of succinic anhydride is significantly reduced to only 95.8%, while in Example 1, the selectivity of succinic anhydride is 99.4%.

[0109] As can be seen from Example 1 and Comparative Example 2, since the second active metal Co described in the present invention is not introduced in the comparative example, under the same reaction conditions as the present invention, the selectivity of succinic anhydride is significantly reduced to only 91.9%, while in Example 1, the selectivity of succinic anhydride is 99.4%.

[0110] From the data comparison of Examples 1-3 and Examples 4-5, it can be seen that the test results of Examples 1-3 are better than those of Examples 4-5. Therefore, when the content value of the active component in the catalyst is within the preferred data range of this application, the catalytic activity and selectivity of the prepared catalyst are better.

[0111] The catalyst prepared in the embodiment of the present invention requires a low reaction pressure, has low requirements on production equipment, and ensures production safety.

[0112] The catalysts prepared in the examples of the present invention exhibit improved maleic anhydride conversion and succinic anhydride selectivity compared to the catalysts prepared in the comparative examples. The improved succinic anhydride selectivity, in particular, is of great significance in industrial production. Firstly, it increases the yield of succinic anhydride, thereby increasing profitability. Secondly, the increased succinic anhydride selectivity improves the purity of the succinic anhydride product, eliminating subsequent purification steps and significantly reducing costs.

[0113] Example 7

[0114] In Example 7, a catalyst was prepared using a method similar to that of Example 1, except that the amounts of the raw materials used were different. The rest were the same as in Example 1, and catalyst S7 was prepared.

[0115] The raw materials used in Example 7 are 29 g of nickel nitrate (Ni(NO3)2·6H2O), 7.26 g of cobalt nitrate (Co(NO3)2·6H2O), and 23.95 g of citric acid (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 1:1), and 30.21 g of SBA-153, an all-silica mesoporous molecular sieve carrier with a pore size range of 6-11 nm, is weighed.

[0116] Based on the total weight of the catalyst S7, the total loading of Ni-Co bimetallic in the catalyst S7 is 19.5wt%; the specific surface area is 508.47m 2 / g, and the average pore volume is 0.854m 3 / g, and the average pore diameter is 6.727nm.

[0117] Example 8

[0118] Example 8 uses a method similar to Example 1 to prepare a catalyst, except that the amount of the raw materials used is different. The rest is the same as Example 1, and catalyst S8 is prepared.

[0119] The raw materials used in Example 8 are 29 g of nickel nitrate (Ni(NO3)2·6H2O), 5.8 g of cobalt nitrate (Co(NO3)2·6H2O), and 22.99 g of citric acid (the molar ratio of Ni(NO3)2·6H2O+Co(NO3)2·6H2O and citric acid is 1:1), and 28.90 g of SBA-12, an all-silica mesoporous molecular sieve carrier with a pore size range of 6-11 nm, is weighed.

[0120] Based on the total weight of the catalyst S8, the total loading of Ni-Co bimetallic in the catalyst S8 is 19.5wt%; the specific surface area is 517.32m 2 / g, and the average pore volume is 0.860m 3 / g, and the average pore diameter is 6.759nm.

[0121] Example 9

[0122] In Example 9, a catalyst was prepared using a method similar to that of Example 1, except that the amounts of the raw materials used were different. The rest were the same as in Example 1, and catalyst S9 was prepared.

[0123] The raw materials used in Example 9 are 17.7 g of nickel acetate (Ni(CH3COO)2), 5.83 g of cobalt nitrate (Co(NO3)2·6H2O), and 23.08 g of citric acid (the molar ratio of Ni(CH3COO)2+Co(NO3)2·6H2O and citric acid is 1:1), and 29.19 g of SBA-15, an all-silica mesoporous molecular sieve carrier with a pore size range of 6-11 nm, is weighed.

[0124] Based on the total weight of the catalyst S9, the total loading of Ni-Co bimetallic in the catalyst S9 is 19.5wt%; the specific surface area is 493.78m 2 / g, and the average pore volume is 0.802m 3 / g, and the average pore diameter is 6.614nm.

[0125] Example 10

[0126] In Example 10, a catalyst was prepared by a method similar to that of Example 1, except that the amounts of the raw materials used were different. The rest were the same as in Example 1, and catalyst S10 was prepared.

[0127] The raw materials used in Example 10 are 29 g of nickel nitrate (Ni(NO3)2·6H2O), 3.53 g of cobalt acetate (Co(CH3COO)2), and 22.99 g of citric acid (the molar ratio of Ni(NO3)2·6H2O+Co(CH3COO)2 and citric acid is 1:1), and 28.90 g of an all-silica mesoporous molecular sieve carrier SBA-15 with a pore size range of 6-11 nm is weighed.

[0128] Based on the total weight of the catalyst S10, the total loading of Ni-Co bimetallic in the catalyst S10 is 19.5wt%; the specific surface area is 495.26m 2 / g, and the average pore volume is 0.808m 3 / g, and the average pore diameter is 6.609nm.

[0129] Example 11

[0130] Example 11 uses a method similar to Example 1 to prepare a catalyst, except that the calcination temperature used is 200° C. The rest is the same as Example 1, and catalyst S11 is prepared.

[0131] Based on the total weight of the catalyst S11, the total loading of Ni-Co bimetallic in the catalyst S11 is 19.5wt%; the specific surface area is 344.57m 2 / g, and the average pore volume is 0.945m 3 / g, and the average pore diameter is 7.359nm.

[0132] Example 12

[0133] In Example 12, a catalyst was prepared using a method similar to that of Example 1, except that the calcination temperature was 600° C. The rest was the same as in Example 1, and catalyst S12 was prepared.

[0134] Based on the total weight of the catalyst S12, the total loading of Ni-Co bimetallic in the catalyst S12 is 19.5wt%; the specific surface area is 544.39m 2 / g, and the average pore volume is 0.493m 3 / g, and the average pore diameter is 6.145nm.

[0135] Example 13

[0136] In Example 13, a catalyst was prepared using a method similar to that of Example 1, except that the calcination temperature was 300° C. The rest was the same as in Example 1, and catalyst S13 was prepared.

[0137] Based on the total weight of the catalyst S13, the total loading of Ni-Co bimetallic in the catalyst S13 is 19.5wt%; the specific surface area is 354.76m 2 / g, and the average pore volume is 0.536m 3 / g, and the average pore diameter is 6.394nm.

[0138] Example 14

[0139] In Example 14, a catalyst was prepared using a method similar to that of Example 1, except that the calcination temperature was 300° C. The rest was the same as in Example 1, and catalyst S14 was prepared.

[0140] Based on the total weight of the catalyst S14, the total loading of Ni-Co bimetallic in the catalyst S14 is 19.5wt%; the specific surface area is 535.29m 2 / g, and the average pore volume is 0.610m 3 / g, and the average pore diameter is 6.297nm.

[0141] While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A catalyst for preparing succinic anhydride by liquid-phase hydrogenation of maleic anhydride, characterized in that: The catalyst includes a carrier and an active component supported on the carrier; The active components include Ni and Co; Based on the total weight of the catalyst as 100%, the loading amount of the active component is 15-25wt%; in the active component, the molar ratio of Ni to Co is 4-6:1; The carrier is an all-silica mesoporous molecular sieve; The preparation method of the catalyst comprises the following steps: (1) After dissolving the metal salt and ligand of the active component in water, a carrier is added to obtain a suspension; (2) drying the suspension to obtain a catalyst precursor; (3) calcining the catalyst precursor under an inert atmosphere to obtain an oxide precursor of the catalyst; (4) reducing the oxide precursor of the catalyst to obtain the catalyst; The ligand is selected from carboxyl multidentate ligands; The carboxyl multidentate ligand is citric acid.

2. The catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride according to claim 1, wherein: Based on the total weight of the catalyst being 100%, the loading amount of the active component is 18-25 wt%.

3. The catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride according to claim 1, wherein: The average pore size of the all-silica mesoporous molecular sieve is 2-50 nm.

4. The catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride according to claim 3, wherein: The average pore size of the all-silica mesoporous molecular sieve is 6-11 nm.

5. The catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride according to claim 1, wherein: The specific surface area of ​​the catalyst is 120-570m 2 / g, average pore volume is 0.4-1.0m 3 / g, and the average pore size is 5.9-7.8nm.

6. The catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride according to claim 1, characterized in that: In step (1), The metal salt of the active component includes a soluble nickel salt and a soluble cobalt salt; and / or, The mass ratio of the metal salt, ligand and carrier of the active component is 1-4:0.4-8:1; and / or, The mass ratio of the water to the carrier is 1-6:

1.

7. The catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride according to claim 1, characterized in that The soluble nickel salt is selected from at least one of nickel nitrate, nickel sulfate, nickel chloride, basic nickel carbonate or nickel acetate; and / or, The soluble cobalt salt is selected from at least one of cobalt nitrate, cobalt sulfate, cobalt chloride or cobalt acetate; and / or, The molar ratio of the soluble nickel salt to the soluble cobalt salt is 4-6:

1.

8. The catalyst for liquid-phase hydrogenation of maleic anhydride to succinic anhydride according to claim 1, characterized in that In step (3), The calcination temperature is 200-600°C and the calcination time is 3-5h; and / or, In step (4), The reduction treatment is carried out at a temperature of 300-700° C. and for a time of 4-6 hours.

9. Use of the catalyst for liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride according to any one of claims 1 to 8 in the reaction of liquid-phase hydrogenation of maleic anhydride to produce succinic anhydride.

10. The use according to claim 9, characterized in that The catalyst, hydrogen and maleic anhydride solution are contacted to react to prepare succinic anhydride; The temperature of the contact reaction is 50-70°C; and / or, The pressure is 1-5MPa.

11. The use according to claim 10, characterized in that The pressure is 1-3MPa.