Ni-based catalyst, preparation method thereof, and method for preparing aminomethylbenzoic acid compounds and cyanobenzylamine compounds using the Ni-based catalyst

Abstract

The invention belongs to the field of chemical industry, and specifically relates to a Ni-based catalyst, a preparation method thereof, and a method for preparing aminomethylbenzoic acid compounds and cyanobenzylamine compounds using the Ni-based catalyst. The Ni-based catalyst of the invention is simple to prepare and has high selectivity; the use of the Ni-based catalyst of the invention to prepare aminomethylbenzoic acid compounds and cyanobenzylamine compounds has high safety, short process flow, is green and harmless, and has significant economic efficiency.

Description

Technical Field

[0001] The invention belongs to the field of chemical industry, and particularly relates to a Ni-based catalyst, a preparation method thereof and a method for preparing aminomethylbenzoic acid compounds and cyanobenzylamine compounds by using the Ni-based catalyst. Background Art

[0002] Aminomethylbenzoic acid compounds, including m-aminomethylbenzoic acid (m-AMPA) and p-aminomethylbenzoic acid (p-AMBA), are important organic intermediates in the fields of materials and medicine. For example, m-AMPA and p-AMBA can be used to synthesize transparent or translucent polyamide materials with high glass transition temperature and high barrier properties (CN113614149A, CN115044033B), which are applied to optical fields such as plastic windows, transparent containers for cosmetic product packaging, glass frames and glass lenses. At the same time, p-aminomethylbenzoic acid is a procoagulant drug with mild toxic side effects and high safety, which is mainly used for bleeding caused by acute and chronic primary fibrin excessive dissolution, localized or systemic hyperfibrinolytic bleeding, such as abnormal bleeding during surgery of the lungs, liver, pancreas, prostate, thyroid, etc. With the continuous in-depth pharmacological research, the medical scope of p-AMBA is constantly expanding. It can not only be used to treat allergic purpura, psoriasis, perioral dermatitis, traumatic secondary hyphema, autoimmune disease pemphigus and other diseases, but also effectively prevent and improve pigmentation in the skin, and is widely used in whitening skin care products. As the application of aminomethylbenzoic acid compounds in the fields of medicine and materials continues to expand, it has become a key intermediate with broad market prospects.

[0003] At present, the synthesis methods of aminomethylbenzoic acid compounds can be classified into three categories:

[0004] (1) Synthesis of aminomethylbenzoic acid by catalytic hydrogenation of cyanobenzoic acid (Source: "National API Process Compilation" pages 506-509). Using p-nitrobenzoic acid as the raw material, p-aminobenzoic acid is obtained through reduction, and then reacted with sodium cyanide after diazotization to generate p-cyanobenzoic acid. Finally, under the catalytic action of Raney Ni, aminomethylbenzoic acid is hydrogenated. This reaction has many steps and uses highly toxic sodium cyanide and highly active Raney Ni catalyst. If used improperly, it is easy to cause accidents and increase safety risks. At the same time, the p-cyanobenzoic acid and the product aminomethylbenzoic acid involved in the hydrogenation process are both high-boiling point substances (boiling point > 300°C), which makes it difficult to purify the product and affects the product quality. The reaction route of the p-cyanobenzoic acid hydrogenation process is as follows:

[0005]

[0006] (2) Using methyl benzoic acid as a raw material, aminomethyl benzoic acid is synthesized by a chlorination-amination process. For example, after methyl benzoic acid is dissolved in chlorobenzene, chlorine is introduced to first synthesize chloromethyl benzoic acid, which is then reacted with ammonia water to generate aminomethyl benzoic acid, and finally refined by an acid-solution-alkali-precipitation method to obtain a P-AMBA product. This process not only uses highly toxic chlorine, but also has many side reactions in the two-step reaction of chlorination and amination, resulting in an overall reaction yield of only 40-50%, generating a large amount of harmful solid waste, and increasing environmental governance costs. The reaction route of the p-methyl benzoic acid chlorination-amination process is as follows:

[0007]

[0008] (3) Using cyanobenzyl chloride as raw material, aminomethylbenzoic acid is prepared by acid hydrolysis and amination. This process route is shorter, but cyanobenzyl chloride is difficult to obtain, and the synthesis process also involves a chlorination process. Not only is the process environmentally unfriendly, but there is no stable supplier in China, the price is expensive, and it is not used for industrial application. The process route of hydrolysis-amination of cyanobenzyl chloride is as follows:

[0009]

[0010] In summary, in the prior art, most of the reaction raw materials are halogenated methyl benzoic acid or halogenated methyl benzonitrile. These substances not only use Cl2 or Br2 as halogenating agents with high toxicity in the preparation process, but also have many side reactions in the halogenation reaction and poor selectivity, which increases the preparation cost of aminomethyl benzoic acid; using halogenated methyl benzoic acid or halogenated methyl benzonitrile as raw materials, after amination, hydrolysis and other steps, using ammonia, urea, urotropine, ammonium bicarbonate and other reagents as amination reagents, resulting in the need to treat a large amount of amine by-products in the subsequent process, increasing the material and energy consumption of the entire process; the raw materials and target products used in the process of synthesizing aminomethyl benzoic acid by catalytic hydrogenation of cyanobenzoic acid are high-boiling point substances (boiling point>300°C), which increases the difficulty of product purification and causes the product purity to be low; and because the Raney Ni catalyst is extremely active and spontaneously ignites when exposed to air, when the Raney Ni catalyst is used as a hydrogenation catalyst, if improper operation occurs, it is easy to cause an accident, which has great safety hazards. Summary of the invention

[0011] In view of the above problems existing in the prior art, the present invention proposes a new method for producing aminomethylbenzoic acid compounds, which uses industrial phthalonitrile compounds as raw materials, selectively hydrogenates cyanobenzylamine over a supported Ni-based catalyst, and then hydrolyzes the phthalonitrile to obtain aminomethylbenzoic acid.

[0012] Specifically, one aspect of the present invention provides a Ni-based catalyst, which comprises SiO2, Ni and a third component, wherein the third component is selected from one or more of CeO2, La2O3, MgO, CaO and BaO; in the Ni-based catalyst, the mass fraction of SiO2 is 30-85%, the mass fraction of Ni is 1-30%, and the mass fraction of the third component is 10-50%; the specific surface area of ​​the Ni-based catalyst is 2-10m 2 / g; the pore size of the Ni-based catalyst is 2-10nm.

[0013] In one or more embodiments, the mass fraction of SiO2 in the Ni-based catalyst is 35-80%.

[0014] In one or more embodiments, the mass fraction of Ni in the Ni-based catalyst is 5-20%.

[0015] In one or more embodiments, in the Ni-based catalyst, the mass fraction of the third component is 15-45%.

[0016] In one or more embodiments, in the Ni-based catalyst, the crystallite size of Ni is 5-20 nm.

[0017] Another aspect of the present invention provides a method for preparing the Ni-based catalyst in any embodiment of the present invention, the method comprising the following steps:

[0018] (1) providing SiO2 pellets; dissolving a Ni source and a third component source in water to obtain a first solution;

[0019] (2) adding the first solution dropwise onto the SiO2 microspheres, allowing the solution to stand after the addition is completed, and then drying and calcining the solution to obtain a catalyst precursor;

[0020] (3) activating the catalyst precursor to obtain the Ni-based catalyst.

[0021] In one or more embodiments, the SiO2 pellets are prepared by the following method: preparing a sodium alginate aqueous solution, adding a silicon source to the sodium alginate aqueous solution, and mixing them uniformly to obtain a sodium alginate-silicon source mixed solution; dripping the sodium alginate-silicon source mixed solution into a solution containing Ca 2+ The sol beads are formed in the aqueous solution of ions; the sol beads are taken out, dried and calcined to obtain the SiO2 beads.

[0022] In one or more embodiments, the concentration of the sodium alginate aqueous solution is 0.5-2 wt %.

[0023] In one or more embodiments, the mass ratio of the sodium alginate aqueous solution to the silicon source is 10:1-1:1.

[0024] In one or more embodiments, the silicon source is selected from one or more of silica sol, white carbon, methyl orthosilicate and ethyl orthosilicate.

[0025] In one or more embodiments, the Ca 2+ The calcium salt used in the aqueous solution of ions is one or more selected from calcium chloride, calcium nitrate, calcium acetate or calcium ethylenediaminetetraacetate, and the Ca 2+ The concentration is 0.5-5wt%.

[0026] In one or more embodiments, the drying temperature is 60-120° C. and the drying time is 8-12 hours.

[0027] In one or more embodiments, the calcination temperature is 450-500° C. and the calcination time is 2-5 hours.

[0028] In one or more embodiments, the Ni source is a soluble Ni salt, and the anion of the soluble Ni salt is preferably one or more selected from nitrate ions, chloride ions, and acetate ions.

[0029] In one or more embodiments, the third component source is a soluble salt containing an M element, wherein the M element is selected from one or more of Ce, La, Mg, Ca and Ba, and the anion of the soluble salt containing the M element is preferably selected from one or more of a nitrate ion, a chloride ion and an acetate ion.

[0030] In one or more embodiments, the molar ratio of the Ni source to the third component source in the first solution is 1:14-4:1.

[0031] In one or more embodiments, in step (2), the standing temperature is 20-80°C and the standing time is 1-8h.

[0032] In one or more embodiments, in step (2), the drying temperature is 60-120° C. and the drying time is 8-12 hours.

[0033] In one or more embodiments, in step (2), the calcination temperature is 300-600° C. and the calcination time is 2-10 h.

[0034] In one or more embodiments, in step (3), the activation atmosphere is hydrogen or a mixture of hydrogen and an inert gas.

[0035] In one or more embodiments, the volume fraction of hydrogen in the mixed gas is 80%-100%, preferably 90%-100%.

[0036] In one or more embodiments, in step (3), the activation pressure is from normal pressure to 0.5 MPa, the temperature is 300-500° C., and the time is 1-5 h. In the present invention, normal pressure is one atmosphere.

[0037] Another aspect of the present invention provides a method for preparing an aminomethylbenzoic acid compound, the method comprising the following steps:

[0038] S1: In the presence of the Ni-based catalyst described in any embodiment of the present invention, a phthalonitrile compound is subjected to a hydrogenation reaction in a solvent to convert a cyano group on the phthalonitrile compound into -CH2NH2 to obtain a cyanobenzylamine compound, wherein the phthalonitrile compound is a compound of formula I Compound of formula II or a compound of formula III In Formula I, Formula II and Formula III, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 and R 12 Each is independently selected from a hydrogen atom, a C1-C10 alkyl group, a C3-C10 cycloalkyl group and a C6-C10 aryl group;

[0039] S2: After the reaction in step S1 is completed, the Ni-based catalyst and the solvent in the reaction system are removed, water is added, mixed evenly, and then the unreacted phthalonitrile compound is separated by filtration to obtain a crude aqueous solution of the cyanobenzylamine compound;

[0040] S3: adding an inorganic acid to the aqueous solution of the crude cyanobenzylamine compound to carry out hydrolysis, so that a cyano group on the cyanobenzylamine compound is converted into a carboxyl group to obtain an aminomethylbenzoic acid compound product.

[0041] In one or more embodiments, in step S1, the solvent is selected from one or more of organic alcohol solvents, organic amide solvents, organic hydrocarbon solvents, organic ether solvents or organic ester solvents.

[0042] In one or more embodiments, the organic alcohol solvent is preferably selected from one or more of methanol, ethanol and isopropanol.

[0043] In one or more embodiments, the organic amide solvent is preferably selected from one or more of N,N-dimethylformamide, N,N-diethylformamide and N,N-dimethylacetamide.

[0044] In one or more embodiments, the organic hydrocarbon solvent is preferably selected from one or more of benzene, toluene and xylene.

[0045] In one or more embodiments, the organic ether solvent is preferably selected from one or more of diethyl ether, methyl ethyl ether, dioxane and tetrahydrofuran.

[0046] In one or more embodiments, the organic ester solvent is preferably selected from one or both of ethyl acetate and methyl acetate.

[0047] In one or more embodiments, in step S1, the mass ratio of the Ni-based catalyst to the phthalonitrile compound is (0.1-1):1.

[0048] In one or more embodiments, in step S1, the mass ratio of the Ni-based catalyst to the phthalonitrile compound is (0.5-1):1.

[0049] In one or more embodiments, in step S1, the temperature of the hydrogenation reaction is 50-180°C.

[0050] In one or more embodiments, in step S1, the temperature of the hydrogenation reaction is 80-150°C.

[0051] In one or more embodiments, in step S1, the temperature of the hydrogenation reaction is 80-120°C.

[0052] In one or more embodiments, in step S1, the hydrogenation reaction pressure is 0.5-5 MPa.

[0053] In one or more embodiments, in step S1, the hydrogenation reaction pressure is 1-5 MPa.

[0054] In one or more embodiments, in step S1, the hydrogenation reaction pressure is 1.5-4 MPa.

[0055] In one or more embodiments, in step S3, the inorganic acid is selected from one or more of hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid.

[0056] In one or more embodiments, in step S3, the inorganic acid is selected from one or both of hydrochloric acid and sulfuric acid.

[0057] In one or more embodiments, the molar ratio of the inorganic acid added in step S3 to the phthalonitrile compound used in step S1 is (1-5):1.

[0058] In one or more embodiments, the molar ratio of the inorganic acid added in step S3 to the phthalonitrile compound used in step S1 is (1-2.5):1.

[0059] In one or more embodiments, in step S3, the hydrolysis after the addition of the inorganic acid includes the following steps: reacting the reaction system at 50-120°C for 60-240min, then cooling to 20-30°C, adding alkali to adjust the pH of the solution to 6.8-7.2, and obtaining an aminomethylbenzoic acid compound product after standing, filtering, and washing.

[0060] Another aspect of the present invention provides a method for preparing a cyanobenzylamine compound, the method comprising the following steps:

[0061] S1: In the presence of the Ni-based catalyst described in any embodiment of the present invention, a phthalonitrile compound is subjected to a hydrogenation reaction in a solvent to convert a cyano group on the phthalonitrile compound into -CH2NH2 to obtain a cyanobenzylamine compound, wherein the phthalonitrile compound is a compound of formula I Compound of formula II or a compound of formula III In Formula I, Formula II and Formula III, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 and R 12 Each is independently selected from a hydrogen atom, a C1-C10 alkyl group, a C3-C10 cycloalkyl group and a C6-C10 aryl group;

[0062] S2: After the reaction in step S1 is completed, the Ni-based catalyst and the solvent in the reaction system are removed, water is added, and after mixing evenly, the unreacted phthalonitrile compound is separated by filtration to obtain a crude aqueous solution of a cyanobenzylamine compound, which is purified to obtain a cyanobenzylamine compound product.

[0063] In one or more embodiments, in step S1, the solvent is selected from one or more of organic alcohol solvents, organic amide solvents, organic hydrocarbon solvents, organic ether solvents or organic ester solvents.

[0064] In one or more embodiments, the organic alcohol solvent is preferably selected from one or more of methanol, ethanol and isopropanol.

[0065] In one or more embodiments, the organic amide solvent is preferably selected from one or more of N,N-dimethylformamide, N,N-diethylformamide and N,N-dimethylacetamide.

[0066] In one or more embodiments, the organic hydrocarbon solvent is preferably selected from one or more of benzene, toluene and xylene.

[0067] In one or more embodiments, the organic ether solvent is preferably selected from one or more of diethyl ether, methyl ethyl ether, dioxane and tetrahydrofuran.

[0068] In one or more embodiments, the organic ester solvent is preferably selected from one or both of ethyl acetate and methyl acetate.

[0069] In one or more embodiments, in step S1, the mass ratio of the Ni-based catalyst to the phthalonitrile compound is (0.1-1):1.

[0070] In one or more embodiments, in step S1, the mass ratio of the Ni-based catalyst to the phthalonitrile compound is (0.5-1):1.

[0071] In one or more embodiments, in step S1, the temperature of the hydrogenation reaction is 50-180°C.

[0072] In one or more embodiments, in step S1, the temperature of the hydrogenation reaction is 80-150°C.

[0073] In one or more embodiments, in step S1, the temperature of the hydrogenation reaction is 80-120°C.

[0074] In one or more embodiments, in step S1, the hydrogenation reaction pressure is 0.5-5 MPa.

[0075] In one or more embodiments, in step S1, the hydrogenation reaction pressure is 1-5 MPa.

[0076] In one or more embodiments, in step S1, the hydrogenation reaction pressure is 1.5-4 MPa. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Figure 1 It is a gas chromatogram of the isophthalonitrile hydrogenation product of Example 1 of the present invention.

[0078] Figure 2 This is a high performance liquid chromatography (HPLC) purity test chart of 3-aminomethylbenzoic acid in Example 1 of the present invention.

[0079] Figure 3 The scanning electron microscope image (left) and texture features (right) of the supported 16Ni / 30MgO-SiO2 catalyst of Example 4 of the present invention.

[0080] Figure 4 The scanning electron microscope image (left) and texture features (right) of the supported 16Ni / 30MgO-SiO2-A catalyst of Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0081] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in this document. Unless otherwise specified, all technical and scientific terms used in this document have the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definitions in this specification shall prevail.

[0082] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0083] Herein, “comprising”, “including”, “containing” and similar terms encompass the meanings of “consisting essentially of” and “consisting of”. For example, when “A comprises B and C” is disclosed herein, “A consists essentially of B and C” and “A consists of B and C” should be deemed to be disclosed herein.

[0084] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are only for brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0085] In this document, unless otherwise specified, percentage refers to mass percentage and ratio refers to mass ratio.

[0086] Herein, the sum of the percentages of the various components of the composition is 100%.

[0087] Herein, when describing embodiments or examples, it should be understood that they are not used to limit the present invention to these embodiments or examples. On the contrary, all substitutes, improvements and equivalents of the methods and materials described in the present invention can be included in the scope defined by the present invention.

[0088] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0089] Ni-based catalysts

[0090] The Ni-based catalyst of the present invention comprises SiO2, Ni and a third component.

[0091] In the present invention, SiO2 is present in the catalyst in the form of oxide. The mass fraction of SiO2 in the Ni-based catalyst of the present invention is 30-85%, such as 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, 75wt%, 80wt%; preferably, the content of SiO2 is 35-80wt%, such as 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, 75wt%;

[0092] In the present invention, Ni is present in the catalyst in the form of a single substance. The mass fraction of Ni in the Ni catalyst of the present invention is 1-30%, such as 2wt%, 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%, 20wt%, 21wt%, 22wt%, 23wt%, 24wt%, 25wt%, 26wt%, 27wt%, 28wt%, 29wt%; preferably 5-20wt%, such as 6wt%, 7wt%, 8wt%, 9wt%, 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt%;

[0093] In the present invention, the third component is present in the catalyst in the form of an oxide. The mass fraction of the third component in the catalyst is calculated based on the mass of the completely burned oxide corresponding to the metal contained in the third component. The third component is one or more selected from CeO2, La2O3, MgO, CaO and BaO. The mass fraction of the third component in the Ni-based catalyst of the present invention is 10-50%, such as 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%; preferably 15-45wt%, such as 20wt%, 25wt%, 30wt%, 35wt%, 40wt%.

[0094] The specific surface area of ​​the Ni-based catalyst of the present invention is preferably 2-10 m 2 / g, for example 3m 2 / g, 4m 2 / g, 5m 2 / g, 6m 2 / g, 7m 2 / g, 8m 2 / g, 9m 2 / g; preferably 3-5.5m 2 / g, for example 3.2m 2 / g, 3.5m 2 / g, 3.8m 2 / g, 4m 2 / g, 4.5m 2 / g, 5m 2 / g, 5.2m 2 / g.

[0095] The pore size of the Ni-based catalyst of the present invention is 2-10 nm, for example, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm; preferably 3-6 nm, for example, 3 nm, 3.4 nm, 4 nm, 4.2 nm, 4.6 nm, 5 nm, 5.6 nm.

[0096] In the Ni-based catalyst of the present invention, the grain size of Ni is preferably 5-20 nm, for example 6 nm, 7 nm, 8 nm, 9 nm, 10 nm, 11 nm, 12 nm, 13 nm, 14 nm, 15 nm, 16 nm, 17 nm, 18 nm, 19 nm.

[0097] Preparation method of Ni-based catalyst

[0098] The Ni-based catalyst of the present invention can be prepared by the following method:

[0099] (1) providing SiO2 pellets; dissolving a Ni source and a third component source in water to obtain a first solution;

[0100] (2) adding the first solution dropwise onto the SiO2 microspheres, allowing the solution to stand after the addition is completed, and then drying and calcining the solution to obtain a catalyst precursor;

[0101] (3) activating the catalyst precursor to obtain the Ni-based catalyst.

[0102] In step (1), the molar ratio of the Ni source to the third component source in the first solution can be 1:14-4:1, for example, 1:13.5, 1:13, 1:12.5, 1:12, 1:11.5, 1:11, 1:10.5, 1:10, 1:9.5, 1:9, 1:8.5, 1:8, 1:7.5, 1:7, 1:6.5, 1:6, 1:5.5, 1:5, 1:4.5, 1:4, 1:3.5, 1:3, 1:2.5, 1:2, 1:1.5, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1.

[0103] In step (2), the standing temperature can be 20-80°C, for example, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C; the time is 1-8h, for example, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h;

[0104] In step (2), the drying temperature can be 60-120°C, for example 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C; and the drying time is 8-12h, for example 8.5h, 9h, 9.5h, 10h, 10.5h, 11h, 11.5h.

[0105] In step (2), the calcination temperature can be 300-600°C, for example 350°C, 400°C, 450°C, 500°C, 550°C; and the calcination time is 2-10h, for example 3h, 4h, 5h, 6h, 7h, 8h, 9h.

[0106] In step (3), the activated atmosphere can be hydrogen or a mixture of hydrogen and an inert gas. In the mixed gas, the volume fraction of hydrogen is preferably 80%-100%, more preferably 90%-100%, such as 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%. The pressure during activation can be normal pressure to 0.5MPa, such as 0.15MPa, 0.2MPa, 0.25MPa, 0.3MPa, 0.35MPa, 0.4MPa, 0.45MPa. The temperature during activation can be 300-500°C, such as 350°C, 400°C, 450°C. The activation time is 1-5h, such as 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h.

[0107] In the present invention, the carrier used to prepare the Ni-based catalyst is preferably SiO2 pellets, which can be prepared by the following method:

[0108] Weigh a certain amount of sodium alginate and dissolve it in distilled water to prepare a sodium alginate solution with a mass fraction of 0.5-2wt% (e.g., 0.6wt%, 0.7wt%, 0.8wt%, 0.9wt%, 1wt%, 1.1wt%, 1.2wt%, 1.3wt%, 1.4wt%, 1.5wt%, 1.6wt%, 1.7wt%, 1.8wt%, 1.9wt%). A certain mass of silicon source is added to the sodium alginate solution, wherein the silicon source is preferably methyl orthosilicate, ethyl orthosilicate, silica sol or white carbon black, wherein the mass ratio of the sodium alginate solution to the silicon source is preferably 10:1-1:1, such as 9:1, 8:1, 7:1, 6:1, 5:1, 4:1, 3:1, 2:1, and the mixture is uniformly mixed, and a Ca-containing solution having a mass fraction of 0.5-5wt% (such as 1wt%, 1.5wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%) is added dropwise. 2+ Aqueous solution of ions (Ca 2+ The aqueous solution of ions is preferably a calcium chloride solution, a calcium nitrate solution, a calcium acetate solution or a calcium ethylenediaminetetraacetic acid solution) to obtain a gel ball. After taking out the gel ball, put it into a blast oven, dry it at 60-120°C (for example, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C) for 8-12h (for example, 8.5h, 9h, 9.5h, 10h, 10.5h, 11h, 11.5h), then put it into a muffle furnace, roast it at 450-500°C (for example, 460°C, 470°C, 480°C, 490°C) for 2-5h (for example, 2.5h, 3h, 3.5h, 4h, 4.5h), take it out, and obtain SiO2 balls.

[0109] The sodium alginate method is to prepare SiO2 beads by mixing sodium alginate with Ca 2+ A gel reaction occurs, wrapping the SiO2 precursor and condensing it into small spherical beads. After drying and calcining, the sodium alginate is removed to form SiO2 small balls. 2+ The main function of sodium alginate is to promote the formation of gel, so it contains Ca 2+ The aqueous solution of ions may be in excess.

[0110] Method for preparing aminomethylbenzoic acid compounds and cyanobenzylamine compounds

[0111] The preparation method of the aminomethylbenzoic acid compound of the present invention specifically comprises the following steps:

[0112] S1: In the presence of the Ni-based catalyst of the present invention, a phthalonitrile compound is subjected to a hydrogenation reaction in a solvent to convert a cyano group on the phthalonitrile compound into -CH2NH2 to obtain a cyanobenzylamine compound, wherein the phthalonitrile compound is a compound of formula I Compound of formula II or a compound of formula III In Formula I, Formula II and Formula III, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 and R 12 Each is independently selected from a hydrogen atom, a C1-C10 alkyl group, a C3-C10 cycloalkyl group and a C6-C10 aryl group;

[0113] S2: After the reaction in step S1 is completed, the Ni-based catalyst and the solvent in the reaction system are removed, water is added, mixed evenly, and then the unreacted phthalonitrile compound is separated by filtration to obtain a crude aqueous solution of the cyanobenzylamine compound;

[0114] S3: adding an inorganic acid to the aqueous solution of the crude cyanobenzylamine compound to carry out hydrolysis, so that a cyano group on the cyanobenzylamine compound is converted into a carboxyl group to obtain an aminomethylbenzoic acid compound.

[0115] In step S1, the phthalonitrile compound is preferably isophthalonitrile or terephthalonitrile.

[0116] In step S1, the mass ratio of SiO2-supported Ni-based catalyst to phthalonitrile compound can be 0.1:1-1:1, for example, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, preferably 0.5:1-1:1, for example, 0.55:1, 0.6:1, 0.65:1, 0.7:1, 0.75:1, 0.8:1, 0.85:1, 0.9:1, 0.95:1.

[0117] In step S1, the hydrogen pressure of the hydrogenation reaction can be 0.5-5MPa, for example, 0.6MPa, 0.7MPa, 0.8MPa, 0.9MPa, 1MPa, 1.5MPa, 2MPa, 2.5MPa, 3MPa, 3.5MPa, 4MPa, 4.5MPa; preferably, 1-5MPa, for example, 1.5MPa, 2MPa, 2.5MPa, 3MPa, 3.5MPa, 4MPa, 4.5MPa; more preferably, 1.5-4MPa, for example, 2MPa, 2.5MPa, 3MPa, 3.5MPa.

[0118] In step S1, the temperature of the hydrogenation reaction can be 50-180°C, such as 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C; preferably 80-150°C, such as 90°C, 100°C, 110°C, 120°C, 130°C, 140°C; more preferably 80-120°C, such as 90°C, 100°C, 110°C. The present invention finds that when the hydrogenation temperature is high, the conversion rate of phthalonitrile compounds is high, but the selectivity of cyanobenzylamine compounds decreases; when the hydrogenation reaction temperature is low, the selectivity of cyanobenzylamine compounds is high, but the conversion rate of phthalonitrile compounds is low; controlling the hydrogenation reaction temperature between 80-150°C is particularly conducive to simultaneously obtaining a high conversion rate of isophthalonitrile compounds and a high selectivity of cyanobenzylamine compounds.

[0119] In step S1, the pressure in the autoclave decreases due to the consumption of hydrogen during the reaction, and hydrogen needs to be introduced to maintain the reaction pressure. When the reaction pressure does not decrease, the reaction is stopped, the autoclave is naturally cooled to room temperature, the hydrogen pressure is removed, and the residual hydrogen in the autoclave is replaced with nitrogen before the reaction product is taken out.

[0120] In step S1, the cyanobenzylamine content can be analyzed by an Agilent 8890 gas chromatograph, and the chromatographic column model is DB624. The temperature is set to 230°C for the injection port and 295°C for the detector, and the column box is heated from 100°C to 260°C by program heating, and the specific program heating method is to keep at 100°C for 10 minutes and then heat to 260°C at 5°C / min.

[0121] The crude aqueous solution of the cyanobenzylamine compound obtained in step S2 is separated and purified to obtain the cyanobenzylamine compound. The separation and purification can be carried out by extraction, chromatography, etc.

[0122] In step S3, the molar ratio of the added inorganic acid to the phthalonitrile compound used in step S1 can be 1:1-5:1, such as 2:1, 3:1, 4:1; preferably 1:1-2.5:1, such as 1.5:1, 2:1.

[0123] In step S3, the base used to adjust the pH of the solution is a common base, such as sodium hydroxide, potassium hydroxide, etc.

[0124] In step S3, after the addition of the inorganic acid is completed, the hydrolysis may include: reacting the reaction system at 50-120°C (e.g., 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C) for 60-240min (e.g., 70min, 80min, 90min, 100min, 110min, 120min, 130min, 140min, 150min); , 160min, 170min, 180min, 190min, 200min, 210min, 220min, 230min), then cooled to 20-30°C (for example, 21°C, 22°C, 23°C, 24°C, 25°C, 26°C, 27°C, 28°C, 29°C), and then adding alkali to adjust the solution pH to 6.8-7.2 (for example, 6.9, 7.0, 7.1), and after standing, filtering and washing, the aminomethylbenzoic acid compound product is obtained.

[0125] In step S3, the purity of aminomethylbenzoic acid in the hydrolyzate can be analyzed by liquid chromatography Waters H-Class high performance liquid chromatography, the chromatographic column model is C18 (4.6m×250mm, 5μm); the mobile phase is phosphate buffer with pH=2.5 / methanol=60 / 40 (v / v), the detection wavelength is 220nm; the flow rate is 1.0ml / min; the injection volume is 20μL; the column temperature is 30°C. The phosphate buffer can be prepared by the following method:

[0126] Take 11.0g of anhydrous sodium dihydrogen phosphate, dissolve it in 500mL of water, add 5mL of triethylamine and 1.4g of sodium dodecyl sulfate, adjust the pH value to 2.5 with dilute phosphoric acid, and dilute to 600ml with water to obtain a phosphate buffer with a pH of 2.5.

[0127] The chromatographic purity of the aminomethylbenzoic acid compound product prepared by the preparation method of the present invention can reach greater than or equal to 99.7%.

[0128] The SiO2-supported Ni-based catalyst prepared by the embodiment of the present invention can effectively inhibit the diffusion of the reaction substrate inside the catalyst, reduce the action time of the catalyst and the reactants, avoid excessive hydrogenation of the dinitrile reaction substrate to synthesize diamines, thereby increasing the yield of nitrile benzylamine compounds.

[0129] The invention discloses a new synthesis method of aminomethylbenzoic acid. The method uses an industrial phthalonitrile compound as a raw material, selectively hydrogenates cyanobenzylamine through a supported Ni-based catalyst, and then hydrolyzes the phthalocyanine to obtain aminomethylbenzoic acid. The process route has not been reported in any public data so far, and belongs to a new synthesis route. The main key points of the route are as follows: (1) the supported Ni-based catalyst is used to avoid the use of a highly dangerous Raney Ni catalyst, the catalyst and product separation process is simple, and the process safety is improved; (2) the raw materials of the route are cheap and easy to obtain, the process flow is short, the yield of aminomethylbenzoic acid is high, and the economic efficiency is significant; (3) a large amount of toxic and harmful organic solvents are not required, the material cost is reduced, and the process of separating these organic substances is reduced, thereby improving the economy and safety of the entire process. At the same time, the environmental pollution is small, and the "three wastes" are simple to treat. It is a green industrial route suitable for large-scale production of aminomethylbenzoic acid.

[0130] The present invention will be described below in the form of specific examples. It should be understood that these examples are illustrative only and are not intended to limit the scope of the present invention. The methods, reagents and materials used in the examples are, unless otherwise stated, conventional methods, reagents and materials in the art. The compounds in the examples can all be purchased through commercial routes.

[0131] In the present invention, the method for determining the specific surface area and pore size of the catalyst is: determining the specific surface area and pore size of the catalyst by nitrogen physical adsorption and desorption.

[0132] In the present invention, the method for determining the crystal size of Ni in the catalyst is: determining the crystal size of Ni in the catalyst by X-ray diffraction.

[0133] In the present invention, the method for determining the mass fractions of SiO2, Ni and the third component in the catalyst is: analyzing the contents of SiO2, Ni and the third component in the catalyst by X-ray fluorescence spectroscopy.

[0134] Herein, the nomenclature of "mNi / n third component-SiO2 catalyst" means that the mass fraction of Ni in the catalyst is m%, and the mass fraction of the third component is n%.

[0135] The SiO2 pellets in Examples 1-9 were prepared as follows:

[0136] Add tetraethyl orthosilicate to a sodium alginate aqueous solution with a mass fraction of 1.5wt%, wherein the mass ratio of the sodium alginate aqueous solution to tetraethyl orthosilicate is 2:1, mix well, and then drip a 1wt% CaCl2 aqueous solution dropwise to obtain gel beads. Take out the gel beads and put them in a blast oven, dry them at 120℃ for 12h, then put them in a muffle furnace, roast them at 450℃ for 3h, take them out, and obtain SiO2 beads.

[0137] Example 1

[0138] Preparation of Ni-based catalyst: Weigh 30g of Ni(NO3)3·6H2O and 28g of Ce(NO3)3·6H2O into a beaker, add 30mL of deionized water, stir and dissolve to prepare solution A; weigh 20g of homemade SiO2 ball carrier, add solution A to the SiO2 ball under stirring, after the addition of solution A, let the SiO2 ball stand at 25℃ for 2h, then put it in a 100℃ oven and dry it for 8h. Grind the dried solid and put it into a muffle furnace, heat it to 550℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain the unreduced 16Ni / 30CeO2-SiO2 catalyst precursor. Before using the catalyst, the catalyst precursor was activated in high-purity hydrogen at 350°C for 3 hours to obtain a supported 16Ni / 30CeO2-SiO2 catalyst (16 and 30 represent the mass percentages of Ni and the third component CeO2 in the catalyst, respectively). The specific surface area of ​​the catalyst is 3.2 m 2 / g, pore size 5.6nm. The crystallite size of Ni in the catalyst is 7.9nm.

[0139] S1: Weigh 10g of isophthalonitrile and place it in a 100mL high-pressure reactor. After adding 5g of loaded 16Ni / 30CeO2-SiO2 catalyst and 50mL of N,N-dimethylformamide, seal the autoclave and fill it with nitrogen to check the airtightness of the reactor. Then carefully replace the gas in the high-pressure reactor with hydrogen three times, fill the hydrogen pressure to 3MPa, heat the reaction system to 120°C and stir rapidly. During the reaction, the pressure in the autoclave drops due to the consumption of hydrogen, and hydrogen needs to be introduced to maintain the reaction pressure at 3MPa. When the reaction pressure does not drop, stop the reaction, cool naturally to 25°C, remove the hydrogen pressure, use nitrogen to replace the residual hydrogen in the reactor three times, and take out the reaction product. The gas chromatogram of the hydrogenation product of isophthalonitrile is shown below. Figure 1 As shown, the gas chromatography detected that the conversion rate of isophthalonitrile was 93%, the selectivity of 3-cyanobenzylamine was 97.1%, and the selectivity of the over-hydrogenation product, meta-xylylenediamine, was 1.8%.

[0140] S2: After taking out the reactants, filter and separate the supported 16Ni / 30CeO2-SiO2 catalyst, remove the N,N-dimethylformamide solvent by distillation, add 1000mL of distilled water, and stir thoroughly to obtain a crude aqueous solution of cyanobenzylamine. The unreacted phthalonitrile raw material can be separated and used as a hydrogenation raw material.

[0141] S3: Place 1000mL of crude cyanobenzylamine aqueous solution in a 2000mL four-necked bottle, add 23.75g of concentrated hydrochloric acid (HCl content 35wt%) dropwise under stirring (the molar ratio of hydrochloric acid:isophthalonitrile is 3:1), heat to 80°C, reflux for 180min, cool to 20°C, add solid NaOH, adjust the solution pH to neutral (6.8-7.2), let stand for 2h, filter the precipitate and rinse the filter cake with cold water and ethanol to obtain 8.77g of 3-aminomethylbenzoic acid solid, with a yield of 74.3%. Figure 2 As shown, the purity of the prepared 3-aminomethylbenzoic acid detected by HPLC was 99.8%.

[0142] Example 2

[0143] Preparation of Ni-based catalyst: weigh 30g of Ni(NO3)3·6H2O and 28g of Ce(NO3)3·6H2O into a beaker, add 30mL of deionized water, stir and dissolve to prepare solution A; weigh 20g of homemade SiO2 ball carrier, add solution A to the SiO2 ball under stirring, after the addition of solution A, let the SiO2 ball stand at 70℃ for 2h, then put it in a 100℃ oven and dry it for 8h. Grind the dried solid and put it into a muffle furnace, heat it to 350℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain unreduced 16Ni / 30CeO2-SiO2 catalyst precursor. Before using the catalyst, activate the catalyst precursor at 350℃ and atmospheric pressure high-purity hydrogen for 3h to obtain a supported 16Ni / 30CeO2-SiO2 catalyst. The specific surface area of ​​the catalyst is 3.2m 2 / g, pore size 5.6nm. The crystallite size of Ni in the catalyst is 5.9nm.

[0144] The 3-aminomethylbenzoic acid of Example 2 was prepared by the same method as Example 1. According to gas chromatography, the conversion rate of isophthalonitrile in the catalytic hydrogenation reaction was 95%, the selectivity of 3-cyanobenzylamine was 95.8%, and the selectivity of over-hydrogenation product meta-phenylenediamine was 1.6%. 9.72 g of 3-aminomethylbenzoic acid solid was obtained by hydrolysis, and the yield was 82.3%. The purity of the obtained 3-aminomethylbenzoic acid by HPLC was 99.8%.

[0145] Example 3

[0146] Preparation of Ni-based catalyst: weigh 30g of Ni(NO3)3·6H2O and 28g of Ce(NO3)3·6H2O into a beaker, add 30mL of deionized water, stir and dissolve to prepare solution A; weigh 20g of homemade SiO2 ball carrier, add solution A to the SiO2 ball under stirring, after the addition of solution A, let the SiO2 ball stand at 50℃ for 2h, then put it in a 60℃ oven and dry it for 8h. Grind the dried solid and put it into a muffle furnace, heat it to 550℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain unreduced 16Ni / 30CeO2-SiO2 catalyst precursor. Before using the catalyst, activate the catalyst precursor at 450℃ in high-purity hydrogen at normal pressure for 3h to obtain a supported 16Ni / 30CeO2-SiO2 catalyst. The specific surface area of ​​the catalyst is 3.2m 2 / g, pore size 5.6nm. The crystallite size of Ni in the catalyst is 10.9nm.

[0147] The 3-aminomethylbenzoic acid of Example 3 was prepared by a method similar to that of Example 1. According to gas chromatography, the conversion rate of isophthalonitrile in the catalytic hydrogenation reaction was 98%, the selectivity of 3-cyanobenzylamine was 97.8%, and the selectivity of the overhydrogenation product meta-phenylenediamine was 1.2%. 10.12 g of solid 3-aminomethylbenzoic acid was obtained by hydrolysis, with a yield of 85.7%. The purity of the obtained 3-aminomethylbenzoic acid by HPLC was 99.8%.

[0148] Example 4

[0149] Preparation of Ni-based catalyst: Weigh 30g of Ni(NO3)3·6H2O and 71g of Mg(NO3)2·6H2O into a beaker, add 30mL of deionized water, stir and dissolve to prepare solution A; weigh 20g of homemade SiO2 ball carrier, add solution A to the SiO2 ball under stirring, after solution A is added, let the SiO2 ball stand at 25℃ for 2h, then put it in a 100℃ oven and dry it for 8h. Grind the dried solid and put it into a muffle furnace, heat it to 450℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain the unreduced 16Ni / 30MgO-SiO2 catalyst precursor. Before using the catalyst, the catalyst precursor was activated in high-purity hydrogen at 350°C for 3 hours to obtain a supported 16Ni / 30MgO-SiO2 catalyst (16 and 30 represent the mass percentages of Ni and the third component MgO in the catalyst, respectively). The specific surface area of ​​the catalyst is 3.8 m 2 / g, pore size 4.6nm, and the grain size of Ni in the catalyst is 12.5nm. Figure 3 The scanning electron microscope image (left) and texture features (right) of the supported 16Ni / 30MgO-SiO2 catalyst of this example are shown.

[0150] S1: Weigh 10g of terephthalonitrile and place it in a 100mL autoclave, add 5g of supported 16Ni / 30MgO-SiO2 catalyst and 50mL of N,N-dimethylformamide, seal the autoclave, and fill it with nitrogen to detect the airtightness of the autoclave. Then carefully replace the gas in the autoclave with hydrogen three times, fill the hydrogen pressure to 1.5MPa, heat the reaction system to 100℃ and stir rapidly. During the reaction, the pressure in the autoclave drops due to the consumption of hydrogen, and hydrogen needs to be introduced to maintain the reaction pressure at 1.5MPa. When the reaction pressure does not drop, stop the reaction, cool naturally to 25℃, remove the hydrogen pressure, replace the residual hydrogen in the autoclave three times with nitrogen, and take out the reaction product. Gas chromatography detected that the conversion rate of terephthalonitrile was 94%, the selectivity of 4-cyanobenzylamine was 98.3%, and the selectivity of over-hydrogenated product p-phenylenediamine was 1.6%.

[0151] S2: After taking out the reactants, filter and separate the supported 16Ni / 30MgO-SiO2 catalyst, remove the toluene solvent by distillation, add 1000mL of distilled water, and stir thoroughly to obtain a crude aqueous solution of cyanobenzylamine. The unreacted phthalonitrile raw material can be separated and used as a hydrogenation raw material.

[0152] S3: 1000mL of crude cyanobenzylamine aqueous solution was placed in a 2000mL four-necked bottle, 15.63g of concentrated sulfuric acid (H2SO4 content 98wt%) was added dropwise under stirring (sulfuric acid / terephthalonitrile=2mol / mol), heated to 80°C, refluxed for 180min, cooled to 20°C, and then solid NaOH was added. After adjusting the solution pH to neutral (6.8-7.2), the solution was allowed to stand for 2h, the precipitate was filtered and the filter cake was rinsed with cold water and ethanol to obtain 9.23g of 4-aminomethylbenzoic acid solid, with a yield of 78.2%. The obtained 4-aminomethylbenzoic acid had a purity of 99.8% by HPLC.

[0153] Example 5

[0154] Preparation of Ni-based catalyst: The supported 16Ni / 30MgO-SiO2 catalyst of Example 5 was prepared by the same method as Example 4.

[0155] S1: Weigh 10g of terephthalonitrile and place it in a 100mL autoclave, add 5g of supported 16Ni / 30MgO-SiO2 catalyst and 50mL of methanol, seal the autoclave, and fill it with nitrogen to detect the airtightness of the autoclave. Then carefully replace the gas in the autoclave with hydrogen three times, fill the hydrogen pressure to 1.5MPa, heat the reaction system to 100℃ and stir rapidly. During the reaction, the pressure in the autoclave drops due to the consumption of hydrogen, and hydrogen needs to be introduced to maintain the reaction pressure at 1.5MPa. When the reaction pressure does not drop, stop the reaction, cool naturally to 25℃, remove the hydrogen pressure, replace the residual hydrogen in the autoclave three times with nitrogen, and take out the reaction product. Gas chromatography detected that the conversion rate of terephthalonitrile was 90%, the selectivity of 4-cyanobenzylamine was 98.3%, and the selectivity of over-hydrogenated product p-phenylenediamine was 1.6%.

[0156] S2: After taking out the reactants, filter and separate the supported 16Ni / 30MgO-SiO2 catalyst, remove the toluene solvent by distillation, add 1000mL of distilled water, and stir thoroughly to obtain a crude aqueous solution of cyanobenzylamine. The unreacted phthalonitrile raw material can be separated and used as a hydrogenation raw material.

[0157] S3: 1000mL of crude cyanobenzylamine aqueous solution was placed in a 2000mL four-necked bottle, 15.63g of concentrated sulfuric acid (H2SO4 content 98wt%) was added dropwise under stirring (sulfuric acid / terephthalonitrile=2mol / mol), heated to 80°C, refluxed for 180min, cooled to 20°C, and then solid NaOH was added. After adjusting the solution pH to neutral (6.8-7.2), the solution was allowed to stand for 2h, the precipitate was filtered and the filter cake was rinsed with cold water and ethanol to obtain 8.85g of 4-aminomethylbenzoic acid solid, with a yield of 74.9%. The obtained 4-aminomethylbenzoic acid had a purity of 99.8% by HPLC.

[0158] Example 6

[0159] Preparation of Ni-based catalyst: Weigh 18g of Ni(NO3)3·6H2O and 26g of La(NO3)3·6H2O into a beaker, add 30mL of deionized water, stir and dissolve to prepare solution A; weigh 20g of homemade SiO2 ball carrier, add solution A dropwise onto the SiO2 ball under stirring, after solution A is added, let the SiO2 ball stand at 25℃ for 2h, then put it in a 100℃ oven and dry it for 8h. Grind the dried solid and put it into a muffle furnace, heat it to 550℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain the unreduced 11Ni / 29La2O3-SiO2 catalyst precursor. Before using the catalyst, the catalyst precursor was activated in high-purity hydrogen at 350°C for 3 hours to obtain a supported 11Ni / 29La2O3-SiO2 catalyst (11 and 29 represent the mass percentages of metal Ni and the third component La2O3 in the catalyst, respectively). The specific surface area of ​​the catalyst is 5.2 m 2 / g, pore size 4.2nm. The crystallite size of Ni in the catalyst is 6.2nm.

[0160] S1: Weigh 20g of terephthalonitrile and place it in a 100mL autoclave, add 10g of supported 11Ni / 29La2O3-SiO2 catalyst and 50mL of ethyl acetate, seal the autoclave, and fill it with nitrogen to detect the airtightness of the autoclave. Then carefully replace the gas in the autoclave with hydrogen three times, fill the hydrogen pressure to 2MPa, heat the reaction system to 90°C and stir rapidly. During the reaction, the pressure in the autoclave drops due to the consumption of hydrogen, and hydrogen needs to be introduced to maintain the reaction pressure at 2MPa. When the reaction pressure does not drop, stop the reaction, cool naturally to 25°C, remove the hydrogen pressure, replace the residual hydrogen in the autoclave three times with nitrogen, and take out the reaction product. Gas chromatography detected that the conversion rate of terephthalonitrile was 93%, the selectivity of 4-cyanobenzylamine was 96.8%, and the selectivity of over-hydrogenated product p-phenylenediamine was 2.9%.

[0161] S2: After taking out the reactants, filter and separate the supported 11Ni / 29La2O3-SiO2 catalyst, remove the ethyl acetate solvent by distillation, add 1000mL of distilled water, and stir thoroughly to obtain a crude aqueous solution of cyanobenzylamine. The unreacted phthalonitrile raw material can be separated and used as a hydrogenation raw material.

[0162] S3: 1000mL of crude cyanobenzylamine aqueous solution was placed in a 2000mL four-necked bottle, 15.63g of concentrated sulfuric acid (H2SO4 content 98wt%) was added dropwise under stirring (sulfuric acid / terephthalonitrile=1mol / mol), heated to 80°C, refluxed for 180min, cooled to 20°C, and then solid NaOH was added. After adjusting the solution pH to neutral (6.8-7.2), the solution was allowed to stand for 2h, the precipitate was filtered and the filter cake was rinsed with cold water and ethanol to obtain 14.37g of 4-aminomethylbenzoic acid solid, with a yield of 60.8%. The obtained 4-aminomethylbenzoic acid had a purity of 99.8% by HPLC.

[0163] Example 7

[0164] Preparation of Ni-based catalyst: Weigh 22g of Ni(NO3)3·6H2O and 51g of La(NO3)3·6H2O into a beaker, add 30mL of deionized water, stir and dissolve to prepare solution A; weigh 20g of homemade SiO2 ball carrier, add solution A to the SiO2 ball under stirring, after solution A is added, let the SiO2 ball stand at 25℃ for 2h, then put it in a 100℃ oven and dry it for 8h. Grind the dried solid and put it into a muffle furnace, heat it to 550℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain the unreduced 10Ni / 44La2O3-SiO2 catalyst precursor. Before using the catalyst, the catalyst precursor was activated in high-purity hydrogen at 350°C for 3 hours to obtain a supported 10Ni / 44La2O3-SiO2 catalyst (10 and 40 represent the mass percentages of metal Ni and the third component La2O3 in the catalyst, respectively). The specific surface area of ​​the catalyst is 5.2 m 2 / g, pore size 3.4nm. The crystal size of Ni in the catalyst is 5.5nm.

[0165] S1: Weigh 10g of terephthalonitrile and place it in a 100mL autoclave, add 10g of supported 10Ni / 44La2O3-SiO2 catalyst and 50mL of tetrahydrofuran, seal the autoclave, and fill it with nitrogen to detect the airtightness of the autoclave. Then carefully replace the gas in the autoclave with hydrogen three times, fill the hydrogen pressure to 4MPa, heat the reaction system to 80°C and stir rapidly. During the reaction, the pressure in the autoclave drops due to the consumption of hydrogen, and hydrogen needs to be introduced to maintain the reaction pressure at 4MPa. When the reaction pressure does not drop, stop the reaction, cool naturally to 25°C, remove the hydrogen pressure, replace the residual hydrogen in the autoclave three times with nitrogen, and take out the reaction product. Gas chromatography detected that the conversion rate of terephthalonitrile was 93%, the selectivity of 4-cyanobenzylamine was 98.1%, and the selectivity of over-hydrogenated product p-phenylenediamine was 1.3%.

[0166] S2: After taking out the reactants, filter and separate the supported 10Ni / 44La2O3-SiO2 catalyst, remove the tetrahydrofuran solvent by distillation, add 1000mL of distilled water, and stir thoroughly to obtain a crude aqueous solution of cyanobenzylamine. The unreacted phthalonitrile raw material can be separated and used as a hydrogenation raw material.

[0167] S3: 1000mL of crude cyanobenzylamine aqueous solution was placed in a 2000mL four-necked bottle, 23.75g of concentrated hydrochloric acid (HCl content 35wt%) was added dropwise under stirring (hydrochloric acid / terephthalonitrile = 3mol / mol), heated to 80°C, refluxed for 180min, cooled to 20°C, and then solid NaOH was added. After adjusting the solution pH to neutral (6.8-7.2), the solution was allowed to stand for 2h, the precipitate was filtered and the filter cake was rinsed with cold water and ethanol to obtain 8.53g of 4-aminomethylbenzoic acid solid, with a yield of 72.2%. The obtained 4-aminomethylbenzoic acid had a purity of 99.7% by HPLC.

[0168] Example 8

[0169] The supported 16Ni / 30CeO2-SiO2 catalyst of Example 8 was prepared by the same method as Example 2, and 4-aminomethylbenzoic acid was prepared using the catalyst:

[0170] In step S1, the hydrogenation step is as follows: weigh 10g of terephthalonitrile and place it in a 100mL autoclave, add 10g of supported 16Ni / 30CeO2-SiO2 catalyst and 50mL of toluene, close the autoclave, and fill it with nitrogen to detect the airtightness of the autoclave. Then carefully replace the gas in the autoclave with hydrogen three times, charge the hydrogen pressure to 4MPa, and heat the reaction system to 180°C and stir rapidly. During the reaction, the pressure in the autoclave decreases due to the consumption of hydrogen, and it is necessary to pass hydrogen to maintain the reaction pressure of 4MPa. When the reaction pressure does not decrease, stop the reaction, cool naturally to 25°C, remove the hydrogen pressure, replace the residual hydrogen in the autoclave three times with nitrogen, and take out the reaction product. Gas chromatography detected terephthalonitrile conversion 98%, 4-cyanobenzylamine selectivity 80.3%, and over-hydrogenation product p-phenylenediamine selectivity 18.4%.

[0171] The operations of steps S2 and S3 are the same as those of Example 2. 7.52 g of solid 4-aminomethylbenzoic acid is obtained in the reaction product, with a yield of 63.7% and a purity of 95.2% as determined by HPLC.

[0172] Example 9

[0173] The supported 16Ni / 30CeO2-SiO2 catalyst of Example 9 was prepared by the same method as Example 1, and 4-aminomethylbenzoic acid was prepared using the catalyst:

[0174] In step S1, the hydrogenation step is as follows: weigh 10g of terephthalonitrile and place it in a 100mL autoclave, add 10g of supported 16Ni / 30CeO2-SiO2 catalyst and 50mL of toluene, close the autoclave, and fill it with nitrogen to detect the airtightness of the autoclave. Then carefully replace the gas in the autoclave with hydrogen three times, charge the hydrogen pressure to 4MPa, and heat the reaction system to 60°C and stir rapidly. During the reaction, the pressure in the autoclave decreases due to the consumption of hydrogen, and it is necessary to pass hydrogen to maintain the reaction pressure at 4MPa. When the reaction pressure does not decrease, stop the reaction, cool naturally to 25°C, remove the hydrogen pressure, replace the residual hydrogen in the autoclave three times with nitrogen, and take out the reaction product. Gas chromatography detected terephthalonitrile conversion 75%, 4-cyanobenzylamine selectivity 98.3%, and over-hydrogenation product p-phenylenediamine selectivity 1.4%.

[0175] The operations of steps S2 and S3 are the same as those of Example 1. 6.34 g of solid 4-aminomethylbenzoic acid is obtained in the reaction product, with a yield of 53.7% and a purity of 98.6% as determined by HPLC.

[0176] Comparative Example 1

[0177] The supported 16Ni / 30MgO-SiO2-A catalyst of Comparative Example 1 was prepared by a method similar to that of Example 4, and 4-cyanobenzylamine was prepared using the catalyst:

[0178] The preparation method of the irregular shaped 16Ni / 30MgO-SiO2-A catalyst in the preparation of Ni-based catalyst is as follows: weigh 30g of Ni(NO3)3·6H2O and 71g of Mg(NO3)2·6H2O and place them in a beaker, add 30mL of deionized water, stir and dissolve to prepare A solution; weigh 20g of gas phase SiO2 (marked as SiO2-A, purchased from Degussa), add A solution dropwise to gas phase SiO2-A under stirring, after the dropwise addition is completed, stand at 25℃ for 2h, put it in a 100℃ oven, and dry it for 8h. Grind the dried solid and place it in a muffle furnace, heat it to 450℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain the unreduced 16Ni / 30MgO-SiO2-A catalyst precursor. Before using the catalyst, the catalyst precursor was activated at 350° C. and atmospheric pressure in high-purity hydrogen for 3 h to obtain a supported 16Ni / 30MgO-SiO2-A catalyst.

[0179] Figure 4 The scanning electron microscope image (left) and texture characteristics (right) of the catalyst of Comparative Example 1 are shown. The catalyst of Comparative Example 1 synthesized using commercial SiO2 has an irregular shape and a specific surface area of ​​80.2 m 2 / g, pore size 20.2nm, and the crystal size of Ni in the catalyst is 3.8nm. The specific surface area and pore size of the catalyst in Comparative Example 1 are significantly higher than those of the catalyst in Example 4. Under the same reaction conditions of S1, the terephthalonitrile conversion rate obtained using the catalyst of Comparative Example 1 is 98%, the 4-cyanobenzylamine selectivity is 5.3%, and the over-hydrogenation product p-phenylenediamine selectivity is 88.4%. Due to the low yield of 4-cyanobenzylamine (less than 1g), no subsequent separation and hydrolysis reaction was carried out. The experimental results show that the structure of the catalyst has a significant effect on its catalytic performance.

[0180] It can be seen from Example 4 and Comparative Example 1 that, compared with using gas-phase SiO2 as a carrier of a Ni-based catalyst, the Ni-based catalyst loaded with SiO2 pellets prepared by the method of the present invention has a smaller specific surface area and narrower pores, which is more conducive to rapid adsorption and desorption of reactants on the catalyst surface, promotes the hydrogenation of a single cyanide group, and inhibits the formation of over-hydrogenation products.

[0181] Comparative Example 2

[0182] The 16Ni / 30CeO2-SiO2-B catalyst of Comparative Example 2 was prepared by a method similar to that of Example 1, and 4-aminomethylbenzoic acid was prepared using the catalyst:

[0183] The preparation of Ni-based catalyst is as follows: 30 g Ni(NO3)3·6H2O and 28 g Ce(NO3)3·6H2O are weighed and placed in a beaker, 30 mL deionized water is added, stirred and dissolved to prepare solution A; 20 g white carbon black (labeled as SiO2-B, purchased from Wacker, with a specific surface area of ​​380 m 2 / g), under stirring, add solution A dropwise onto white carbon black. After the addition is completed, let it stand for 2h at 25℃, then put it into a 100℃ oven and dry it for 8h. Grind the dried solid and put it into a muffle furnace, heat it to 550℃ at a heating rate of 1℃ / min, and calcine it in air for 4h. Obtain an unreduced 16Ni / 30CeO2-SiO2-B catalyst precursor. Before using the catalyst, activate the catalyst precursor at 350℃ in high-purity hydrogen at normal pressure for 3h to obtain a supported 16Ni / 30CeO2-SiO2-B catalyst.

[0184] S1: Weigh 10g of terephthalonitrile and place it in a 100mL autoclave, add 10g of supported 16Ni / 30CeO2-SiO2-B catalyst and 50mL of toluene, and then seal the autoclave. Fill nitrogen to test the airtightness of the reactor. Then carefully replace the gas in the autoclave with hydrogen three times, then fill the hydrogen pressure to 4MPa, heat to 120°C and stir rapidly. During the reaction, the pressure in the autoclave drops due to the consumption of hydrogen, and hydrogen needs to be introduced to maintain the reaction pressure at 4MPa. When the reaction pressure does not drop, stop the reaction, cool naturally to 25°C, remove the hydrogen pressure, replace the residual hydrogen in the autoclave three times with nitrogen, and take out the reaction product. Gas chromatography detected that the conversion rate of terephthalonitrile was 99%, the selectivity of 4-cyanobenzylamine was 40.9%, and the selectivity of over-hydrogenated product p-phenylenediamine was 58.1%.

[0185] The operation of steps S2 and S3 is the same as that of Example 1. 2.53 g of 4-aminomethylbenzoic acid solid is obtained in the reaction product, with a yield of 21.4% and a purity of 92.6% by HPLC. The experimental results show that the selectivity of 4-cyanobenzylamine of the 16Ni / 30CeO2-SiO2-B catalyst synthesized by direct impregnation of white carbon black is significantly reduced.

Claims

1. A Ni-based catalyst, characterized in that The Ni-based catalyst comprises SiO2, Ni and a third component, wherein the third component is selected from one or more of CeO2, La2O3, MgO, CaO and BaO; in the Ni-based catalyst, the mass fraction of SiO2 is 30-85%, the mass fraction of Ni is 1-30%, and the mass fraction of the third component is 10-50%; the specific surface area of ​​the Ni-based catalyst is 2-10m 2 / g; the pore size of the Ni-based catalyst is 2-10nm.

2. The Ni-based catalyst according to claim 1, characterized in that The Ni-based catalyst has one or more of the following characteristics: In the Ni-based catalyst, the mass fraction of SiO2 is 35-80%; In the Ni-based catalyst, the mass fraction of Ni is 5-20%; In the Ni-based catalyst, the mass fraction of the third component is 15-45%; In the Ni-based catalyst, the grain size of Ni is 5-20 nm.

3. A method for preparing a Ni-based catalyst according to claim 1 or 2, characterized in that: The method comprises the following steps: (1) providing SiO2 pellets; dissolving a Ni source and a third component source in water to obtain a first solution; (2) adding the first solution dropwise onto the SiO2 microspheres, allowing the solution to stand after the addition is completed, and then drying and calcining the solution to obtain a catalyst precursor; (3) activating the catalyst precursor to obtain the Ni-based catalyst.

4. The method according to claim 3, characterized in that The SiO2 beads are prepared by the following method: preparing a sodium alginate aqueous solution, adding a silicon source to the sodium alginate aqueous solution, and mixing them evenly to obtain a sodium alginate-silicon source mixed solution; dropping the sodium alginate-silicon source mixed solution into a solution containing Ca 2+ The sol beads are formed in the aqueous solution of ions; the sol beads are taken out, dried and calcined to obtain the SiO2 beads.

5. The method according to claim 4, characterized in that The method for preparing SiO2 spheres has one or more of the following characteristics: The concentration of the sodium alginate aqueous solution is 0.5-2wt%; The mass ratio of the sodium alginate aqueous solution to the silicon source is 10:1-1:1; The silicon source is selected from one or more of silica sol, white carbon black, methyl orthosilicate and ethyl orthosilicate; The Ca 2+ The aqueous solution of ions contains one or more calcium salts selected from calcium chloride, calcium nitrate, calcium acetate and calcium ethylenediaminetetraacetate; The Ca 2+ Ion in aqueous solution Ca 2+ Concentration of 0.5-5wt%; The drying temperature is 60-120°C and the drying time is 8-12h; The calcination temperature is 450-500° C. and the calcination time is 2-5 hours.

6. The method according to claim 3, characterized in that The method has one or more of the following features: The Ni source is a soluble Ni salt, and the anion of the soluble Ni salt is preferably one or more selected from nitrate ions, chloride ions and acetate ions; The third component source is a soluble salt containing an M element, wherein the M element is selected from one or more of Ce, La, Mg, Ca and Ba, and the anion of the soluble salt containing an M element is preferably selected from one or more of a nitrate ion, a chloride ion and an acetate ion; The molar ratio of the Ni source to the third component source in the first solution is 1:14-4:1; In step (2), the standing temperature is 20-80° C. and the standing time is 1-8 h; In step (2), the drying temperature is 60-120° C. and the drying time is 8-12 hours; In step (2), the calcination temperature is 300-600°C and the time is 2-10h; In step (3), the activation atmosphere is hydrogen or a mixture of hydrogen and an inert gas, and the volume fraction of hydrogen in the mixture is preferably 80%-100%, more preferably 90%-100%; In step (3), the activation pressure is from normal pressure to 0.5 MPa, the temperature is 300-500° C., and the time is 1-5 h.

7. A method for preparing an aminomethylbenzoic acid compound, characterized in that: The method comprises the following steps: S1: In the presence of the Ni-based catalyst of claim 1 or 2, a phthalonitrile compound is subjected to a hydrogenation reaction in a solvent to convert a cyano group on the phthalonitrile compound into -CH2NH2 to obtain a cyanobenzylamine compound, wherein the phthalonitrile compound is a compound of formula I Compound of formula II or a compound of formula III In Formula I, Formula II and Formula III, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 and R 12 Each is independently selected from a hydrogen atom, a C1-C10 alkyl group, a C3-C10 cycloalkyl group and a C6-C10 aryl group; S2: After the reaction in step S1 is completed, the Ni-based catalyst and the solvent in the reaction system are removed, water is added, mixed evenly, and then the unreacted phthalonitrile compound is separated by filtration to obtain a crude aqueous solution of the cyanobenzylamine compound; S3: adding an inorganic acid to the aqueous solution of the crude cyanobenzylamine compound to carry out hydrolysis, so that a cyano group on the cyanobenzylamine compound is converted into a carboxyl group to obtain an aminomethylbenzoic acid compound product.

8. The method according to claim 7, characterized in that The method has one or more of the following features: In step S1, the solvent is selected from one or more of organic alcohol solvents, organic amide solvents, organic hydrocarbon solvents, organic ether solvents or organic ester solvents; the organic alcohol solvent is preferably selected from one or more of methanol, ethanol and isopropanol; the organic amide solvent is preferably selected from one or more of N,N-dimethylformamide, N,N-diethylformamide and N,N-dimethylacetamide; the organic hydrocarbon solvent is preferably selected from one or more of benzene, toluene and xylene; the organic ether solvent is preferably selected from one or more of diethyl ether, methyl ethyl ether, dioxane and tetrahydrofuran; the organic ester solvent is preferably selected from one or both of ethyl acetate and methyl acetate; In step S1, the mass ratio of the Ni-based catalyst to the phthalonitrile compound is (0.1-1):1, preferably (0.5-1):1; In step S1, the temperature of the hydrogenation reaction is 50-180°C, preferably 80-150°C, more preferably 80-120°C; In step S1, the hydrogenation reaction pressure is 0.5-5 MPa, preferably 1-5 MPa, more preferably 1.5-4 MPa; In step S3, the inorganic acid is selected from one or more of hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid, preferably one or two of hydrochloric acid and sulfuric acid; The molar ratio of the inorganic acid added in step S3 to the phthalonitrile compound used in step S1 is (1-5):1, preferably (1-2.5):1; In step S3, the hydrolysis after the addition of the inorganic acid is completed The method comprises the following steps: reacting the reaction system at 50-120° C. for 60-240 minutes, cooling the system to 20-30° C., adding alkali to adjust the pH value of the solution to 6.8-7.2, standing, filtering and washing to obtain an aminomethylbenzoic acid compound product.

9. A method for preparing a cyanobenzylamine compound, characterized in that: The method comprises the following steps: S1: In the presence of the Ni-based catalyst of claim 1 or 2, a phthalonitrile compound is subjected to a hydrogenation reaction in a solvent to convert a cyano group on the phthalonitrile compound into -CH2NH2 to obtain a cyanobenzylamine compound, wherein the phthalonitrile compound is a compound of formula I Compound of formula II or a compound of formula III In Formula I, Formula II and Formula III, R1, R2, R3, R4, R5, R6, R7, R8, R9, R 10 , R 11 and R 12 Each is independently selected from a hydrogen atom, a C1-C10 alkyl group, a C3-C10 cycloalkyl group and a C6-C10 aryl group; S2: After the reaction in step S1 is completed, the Ni-based catalyst and the solvent in the reaction system are removed, water is added, and after mixing evenly, the unreacted phthalonitrile compound is separated by filtration to obtain a crude aqueous solution of a cyanobenzylamine compound, which is purified to obtain a cyanobenzylamine compound product.

10. The method according to claim 9, characterized in that The method has one or more of the following features: In step S1, the solvent is selected from one or more of organic alcohol solvents, organic amide solvents, organic hydrocarbon solvents, organic ether solvents or organic ester solvents; the organic alcohol solvent is preferably selected from one or more of methanol, ethanol and isopropanol; the organic amide solvent is preferably selected from one or more of N,N-dimethylformamide, N,N-diethylformamide and N,N-dimethylacetamide; the organic hydrocarbon solvent is preferably selected from one or more of benzene, toluene and xylene; the organic ether solvent is preferably selected from one or more of diethyl ether, methyl ethyl ether, dioxane and tetrahydrofuran; the organic ester solvent is preferably selected from one or both of ethyl acetate and methyl acetate; In step S1, the mass ratio of the Ni-based catalyst to the phthalonitrile compound is (0.1-1):1, preferably (0.5-1):1; In step S1, the temperature of the hydrogenation reaction is 50-180°C, preferably 80-150°C, more preferably 80-120°C; In step S1, the hydrogenation reaction pressure is 0.5-5 MPa, preferably 1-5 MPa, and more preferably 1.5-4 MPa.

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