A Raney nickel composite material and its preparation method and application

Abstract

The present invention provides a Raney nickel composite material, its preparation method, and application, belonging to the field of catalyst technology. The present invention provides a Raney nickel composite material comprising a carrier and Raney nickel loaded on the carrier; the carrier is porous carbon co-doped with Ni, B, and N; the molar ratio of B to N is 1:1 to 5. The present invention loads the Raney nickel on the porous carbon, improving the dispersion of the Raney nickel. The Ni doping enhances the interaction between the porous carbon and the Raney nickel, thereby reducing the aggregation and loss of the Raney nickel and improving its stability and catalytic activity. Furthermore, the present invention introduces B and N into the Raney nickel composite material and adjusts their ratio to produce a synergistic effect, changing the electronic structure of the nickel in the Raney nickel and thereby changing the dispersion of the Raney nickel, further enhancing the stability and catalytic activity of the composite material.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalysts, and in particular relates to a Raney nickel composite material and a preparation method and application thereof. Background Art

[0002] Raney nickel, also known as sponge nickel or skeletal nickel, is typically extracted from Ni-Al alloys through superalkaline etching. It is a fine-grained solid powder composed primarily of nickel. Each particle in the powder exhibits a three-dimensional network with irregular pores, shapes, and orientations. These properties are attributed to the unique superalkaline etching process, which also results in its high catalytic activity.

[0003] The excellent catalytic activity and the ability of hydrogen generated during superalkaline etching to be stored in the catalyst pores have led to the widespread application of Raney nickel in catalytic hydrogenation reactions. However, its only drawback is its instability and its inactivation under high temperature and pressure. Summary of the Invention

[0004] The purpose of the present invention is to provide a Raney nickel composite material and a preparation method and application thereof. The Raney nickel composite material of the present invention has both good catalytic activity and stability.

[0005] The present invention provides a Raney nickel composite material, comprising a carrier and Raney nickel loaded on the carrier; the carrier is porous carbon co-doped with Ni, B and N elements; and the molar ratio of the B element to the N element is 1:1-5.

[0006] Preferably, the content of Raney nickel in the Raney nickel composite material is 6 to 20 wt%.

[0007] Preferably, the content of Ni element in the carrier is 3 to 15 wt%.

[0008] Preferably, the content of element B in the carrier is 1 to 5 wt%.

[0009] Preferably, the specific surface area of ​​the Raney nickel composite material is 468.2 to 1012.4 m 2 / g.

[0010] The present invention also provides a method for preparing the Raney nickel composite material described in the above scheme, comprising the following steps:

[0011] A carbon-containing polymer, a boron-containing compound, a nitrogen-containing compound, and a first nickel salt are loaded onto a hard template by an impregnation method to obtain a hard template wrapped with a porous carbon precursor; the ratio of the amount of the B element in the boron-containing compound to the amount of the N element in the nitrogen-containing compound is 1:1 to 8.5; and the hard template comprises one of silicon dioxide crystals, sodium chloride, calcium carbonate, and magnesium oxide;

[0012] calcining the hard template wrapped by the porous carbon precursor to obtain a hard template wrapped by the porous carbon precursor;

[0013] The porous carbon-wrapped hard template is mixed with a second nickel salt and an aluminum salt, and then subjected to a second calcination to generate a nickel-aluminum alloy to obtain a Raney nickel composite material precursor;

[0014] The Raney nickel composite material precursor is etched to remove the hard template agent to obtain the Raney nickel composite material.

[0015] Preferably, the mass ratio of the boron-containing compound to the first nickel salt is 2 to 5:1; the boron-containing compound comprises one of boric acid, phenylboric acid, p-aminophenylboric acid and 2-naphthaleneboric acid;

[0016] The first nickel salt comprises one of nickel nitrate hexahydrate, nickel chloride, nickel acetate, nickel phosphate and nickel acetylacetonate;

[0017] The nitrogen-containing compound includes one of urea, melamine, cyanamide and dicyandiamide.

[0018] Preferably, the mass ratio of the carbon-containing polymer to the first nickel salt is 10 to 30:1; the carbon-containing polymer comprises one of polyether, phenolic resin and polyvinyl pyrrolidone;

[0019] The mass ratio of the first nickel salt to the hard template is 0.05-0.8:1.

[0020] Preferably, the mass ratio of the porous carbon-wrapped hard template to the second nickel salt is 1 to 8:1;

[0021] The second nickel salt includes one of nickel nitrate hexahydrate, nickel chloride, nickel acetate, nickel phosphate and nickel acetylacetonate.

[0022] The present invention also provides the use of the Raney nickel composite material described in the above scheme or the Raney nickel composite material prepared by the preparation method described in the above scheme as a catalyst in the hydrogenation of nitro compounds to prepare amine compounds.

[0023] The present invention provides a Raney nickel composite material comprising a support and Raney nickel supported on the support; the support is porous carbon co-doped with Ni, B, and N; the molar ratio of B to N is 1:1 to 5. The Raney nickel supported on the porous carbon improves its dispersibility. The Ni doping enhances the interaction between the porous carbon and the Raney nickel, thereby reducing Raney nickel aggregation and loss, and improving stability and catalytic activity. Furthermore, the present invention introduces B and N into the Raney nickel composite material and adjusts their ratio to create a synergistic effect, altering the electronic structure of the nickel in the Raney nickel. This increases the interaction between the Raney nickel and the support, prevents Raney nickel aggregation, improves Raney nickel dispersibility, and further enhances the stability and catalytic activity of the composite material. Experimental results show that the Raney nickel composite material can achieve a nitrobenzene conversion rate of up to 99.5% when catalyzing nitrobenzene. Even after 10 cycles of catalytic nitrobenzene conversion, the nitrobenzene conversion rate still reached 98.8%. DETAILED DESCRIPTION

[0024] The present invention provides a Raney nickel composite material, comprising a carrier and Raney nickel loaded on the carrier; the carrier is porous carbon co-doped with Ni, B and N elements; and the molar ratio of the B element to the N element is 1:1-5.

[0025] In the present invention, the content of Raney nickel in the Raney nickel composite material is preferably 6-20wt%, more preferably 10-18wt%, and further preferably 12-15wt%; the content of Ni element in the carrier is preferably 3-15wt%, more preferably 5-10wt%, and further preferably 6-8wt%; the content of B element in the carrier is preferably 1-5wt%, more preferably 2-4wt%, and further preferably 2.5-3wt%. In the present invention, the molar ratio of the B element to the N element is 1:1-5, preferably 1:2-4, and more preferably 1:3-3.7. In the present invention, the specific surface area of ​​the Raney nickel composite material is preferably 468.2-1012.4m 2 / g, more preferably 500 to 1000 m 2 / g, more preferably 600 to 800 m 2 In the present invention, the structure of the Raney nickel composite material is preferably a hollow spherical structure, and the inner diameter of the Raney nickel composite material is preferably 50-100 nm.

[0026] The present invention loads Raney nickel onto porous carbon, improving the dispersion of Raney nickel. Furthermore, the Ni doping enhances the interaction between the porous carbon and the Raney nickel, thereby reducing the aggregation and loss of Raney nickel and improving stability and catalytic activity. Furthermore, the present invention introduces B and N elements into the Raney nickel composite material and adjusts their ratio to produce a synergistic effect, thereby changing the electronic structure of nickel in the Raney nickel and thus changing the dispersibility of the Raney nickel, further enhancing the stability and catalytic activity of the composite material.

[0027] The present invention also provides a method for preparing the Raney nickel composite material described in the above scheme, comprising the following steps:

[0028] A carbon-containing polymer, a boron-containing compound, a nitrogen-containing compound, and a first nickel salt are loaded onto a hard template by an impregnation method to obtain a hard template wrapped with a porous carbon precursor; the ratio of the amount of the B element in the boron-containing compound to the amount of the N element in the nitrogen-containing compound is 1:1 to 8.5; and the hard template comprises one of silicon dioxide crystals, sodium chloride, calcium carbonate, and magnesium oxide;

[0029] calcining the hard template wrapped by the porous carbon precursor to obtain a hard template wrapped by the porous carbon precursor;

[0030] The porous carbon-wrapped hard template is mixed with a second nickel salt and an aluminum salt, and then subjected to a second calcination to generate a nickel-aluminum alloy to obtain a Raney nickel composite material precursor;

[0031] The Raney nickel composite material precursor is etched to remove the hard template agent to obtain the Raney nickel composite material.

[0032] The present invention loads a carbon-containing polymer, a boron-containing compound and a nitrogen-containing compound on a hard template by an impregnation method to obtain a hard template wrapped by a porous carbon precursor.

[0033] In the present invention, the impregnation method preferably includes the following steps: after mixing the carbon-containing polymer, the boron-containing compound, the nitrogen-containing compound and the first nickel salt with a solvent, dispersing the hard template in the resulting mixture, and then drying the resulting dispersion to obtain the hard template wrapped by the porous carbon precursor. In the present invention, the ratio of the amount of the B element in the boron-containing compound to the amount of the N element in the nitrogen-containing compound is 1:1 to 8.5, preferably 1:2 to 6, and more preferably 1:4 to 5. The present invention has no special restrictions on the mixing and dispersion, and a scheme familiar to those skilled in the art can be adopted. Specifically, in the embodiment of the present invention, the mixing is stirred for 1 hour, and the dispersion is stirred for 2 hours. In the present invention, the solvent is preferably an ethanol solution. The volume ratio of ethanol to water in the ethanol solution is preferably 1:1 to 4. The present invention has no special restrictions on the amount of the solvent, and the carbon-containing polymer, the boron-containing compound, the nitrogen-containing compound and the first nickel salt can be fully mixed. The present invention uses an ethanol solution to facilitate dispersion of the carbon-containing polymer, the boron-containing compound, the nitrogen-containing compound, the first nickel salt, and the hard template, and also facilitates rapid evaporation to dryness at a relatively low temperature. In the present invention, the drying temperature is preferably 50-100°C, more preferably 60-80°C, and the drying time is preferably 3-10 hours, more preferably 4-8 hours, and even more preferably 5-6 hours.

[0034] In the present invention, the mass ratio of the carbon-containing polymer to the first nickel salt is preferably 10 to 60:1, more preferably 20 to 50:1, and even more preferably 30 to 40:1. In the present invention, the carbon-containing polymer preferably comprises one of polyether, phenolic resin, and polyvinyl pyrrolidone, more preferably phenolic resin. In the present invention, the first nickel salt preferably comprises one of nickel nitrate hexahydrate, nickel chloride, nickel acetate, nickel phosphate, and nickel acetylacetonate, more preferably nickel nitrate hexahydrate.

[0035] In the present invention, the mass ratio of the boron-containing compound to the first nickel salt is preferably 2 to 6.5: 1, more preferably 3 to 4: 1. In the present invention, the boron-containing compound comprises one of boric acid, phenylboric acid, p-aminophenylboric acid and 2-naphthaleneboric acid, more preferably boric acid.

[0036] In the present invention, the nitrogen-containing compound preferably includes one of urea, melamine, cyanamide and dicyandiamide, and more preferably melamine.

[0037] In the present invention, the mass ratio of the first nickel salt to the hard template is preferably 0.05 to 0.8:1, more preferably 0.4 to 0.6:1. In the present invention, the particle size of the hard template is preferably 10 to 200 nm, more preferably 20 to 150 nm, and further preferably 50 to 100 nm. In the present invention, the hard template comprises one of silicon dioxide crystals, sodium chloride, calcium carbonate and magnesium oxide. The hard template of the present invention can form the prepared Raney nickel composite material into regular spheres with good morphology.

[0038] After obtaining the hard template wrapped by the porous carbon precursor, the present invention performs a first calcination on the hard template wrapped by the porous carbon precursor to obtain a hard template wrapped by the porous carbon. In the present invention, the temperature of the first calcination is preferably 500-1000°C, more preferably 800-900°C; the holding time is preferably 1-5h, more preferably 2-4h. The first calcination is preferably carried out in nitrogen or an inert gas. After the first calcination, porous carbon containing Ni, B and N elements is generated, and the porous carbon is coated on the hard template.

[0039] After obtaining the porous carbon-wrapped hard template, the present invention mixes the porous carbon-wrapped hard template with a second nickel salt and an aluminum salt and performs a second calcination to generate a nickel-aluminum alloy to obtain a Raney nickel composite material precursor. In the present invention, the mass ratio of the porous carbon-wrapped hard template to the second nickel salt is 1 to 8:1, preferably 3.5 to 4.5:1. In the present invention, the mass ratio of the second nickel salt to the aluminum salt is preferably 0.2 to 8:1, more preferably 2 to 6:1, and further preferably 3 to 5:1. In the present invention, the second nickel salt preferably includes one of nickel nitrate hexahydrate, nickel chloride, nickel acetate, nickel phosphate and nickel acetylacetonate, more preferably nickel chloride. In the present invention, the aluminum salt preferably includes one of aluminum chloride, aluminum phosphate, aluminum acetate and aluminum triethanolate, more preferably aluminum chloride.

[0040] In the present invention, the mixing method is preferably grinding. The present invention has no special limitation on the grinding time, as long as the mixing is uniform. Specifically, in an embodiment of the present invention, the grinding time is 2 hours. In the present invention, the temperature of the second calcination is preferably 100-500°C, more preferably 200-400°C; the holding time is preferably 0.5-4 hours, more preferably 1-3 hours. In the present invention, the second calcination is preferably carried out in nitrogen or an inert gas. During the second calcination, the second nickel salt and the aluminum salt react to form a nickel-aluminum alloy.

[0041] After obtaining the Raney nickel composite material precursor, the present invention etches the Raney nickel composite material precursor to remove the hard template agent to obtain the Raney nickel composite material.

[0042] In the present invention, when the hard template is a silicon dioxide crystal, the etching is performed using a strong alkaline solution, and the concentration of the strong alkaline solution is preferably 2 to 9 mol / L, more preferably 4 to 6 mol / L. In the present invention, the strong alkaline solution preferably includes a potassium hydroxide solution or a sodium hydroxide solution, more preferably a sodium hydroxide solution. The present invention does not specifically limit the amount of the strong alkaline solution used during the etching and the etching time. The hard template and the aluminum in the nickel-aluminum alloy can be removed using a method familiar to those skilled in the art.

[0043] When the hard template is calcium carbonate and / or magnesium oxide, the etching is preferably performed with a strong alkaline solution and then with an acidic solution. The present invention does not specifically limit the amount of the strong alkaline solution and the etching time, and the aluminum in the nickel-aluminum alloy can be removed using a method well known to those skilled in the art. The present invention does not specifically limit the type, amount, and etching time of the acidic solution during the etching, and the hard template can be removed using a method well known to those skilled in the art.

[0044] When the hard template is sodium chloride, the etching is preferably performed with water followed by etching with an alkaline solution. The present invention does not specifically limit the amount of water used during the etching or the etching time, and the hard template can be removed using a method well known to those skilled in the art. The present invention does not specifically limit the amount of the strong alkaline solution used or the etching time, and the aluminum in the nickel-aluminum alloy can be removed using a method well known to those skilled in the art.

[0045] The present invention removes the hard template agent by etching to obtain a Raney nickel composite material with an inner diameter consistent with the particle size of the hard template agent.

[0046] The present invention uses silicon dioxide as a hard template to prepare a porous carbon material, and loads a nickel-aluminum alloy through a direct calcination method, and then prepares a composite material of Raney nickel loaded on porous carbon through a superalkaline etching method. The composite material has higher stability and a high specific surface area, which is beneficial to the distribution of active components and the improvement of catalytic activity.

[0047] The present invention also provides the use of the Raney nickel composite material described in the above scheme or the Raney nickel composite material prepared by the preparation method described in the above scheme as a catalyst in the hydrogenation of nitro compounds to prepare amine compounds, preferably as a catalyst in the hydrogenation of nitrobenzene to prepare aniline.

[0048] In the present invention, the preparation of aniline by hydrogenation of nitrobenzene preferably comprises the following steps:

[0049] Nitrobenzene, a Raney nickel composite material, an organic solvent and hydrogen are mixed and subjected to a hydrogenation reaction to obtain aniline.

[0050] In the present invention, the mass ratio of the nitrobenzene to the Raney nickel composite material is preferably 2 to 60:1, more preferably 10 to 50:1, and further preferably 20 to 30:1. In the present invention, the organic solvent is preferably ethanol. The volume ratio of the mass of the Raney nickel composite material to the organic solvent is preferably 10 mg:1 mL. In the present invention, the temperature of the hydrogenation reaction is preferably 40 to 120°C, more preferably 50 to 100°C, and further preferably 60 to 80°C. The pressure of the hydrogenation reaction is preferably 0.5 to 5 MPa, more preferably 1 to 4 MPa, and further preferably 2 to 3 MPa. In the present invention, the pressure is preferably provided by hydrogen.

[0051] In the present invention, the hydrogenation reaction is preferably carried out in a high-pressure reactor.

[0052] To further illustrate the present invention, the Raney nickel composite material provided by the present invention, its preparation method and application are described in detail below with reference to the examples, but they should not be construed as limiting the scope of protection of the present invention.

[0053] Example 1

[0054] 1) 5 g of phenolic resin, 1.3 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0055] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0056] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.2 wt %, the content of B element is 3 wt %; and the molar ratio of B element to N element is 1:3.7;

[0057] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, followed by calcination at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0058] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0059] In the Raney nickel composite material of Example 1, the content of Raney nickel is 13.1 wt %.

[0060] Application Example 1

[0061] The Raney nickel composite material obtained in Example 1 was placed in an autoclave and subjected to hydrogenation of nitrobenzene to produce aniline at 60°C, a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1 for 0.5 h using ethanol as the solution. The liquid was collected and analyzed by gas chromatography (Table 2). Stability testing is shown in Table 3.

[0062] Example 2

[0063] 1) 5 g of phenolic resin, 1.0 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0064] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0065] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.1 wt %, the content of B element is 2.4 wt %; and the molar ratio of B element to N element is 1:5;

[0066] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, and finally calcining the mixture at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0067] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0068] In the Raney nickel composite material of Example 2, the content of Raney nickel is 13.2 wt %.

[0069] Application Example 2

[0070] The Raney nickel composite material obtained in Example 2 was placed in an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60° C., a reaction pressure of 0.8 MPa hydrogen, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0071] Example 3

[0072] 1) 5 g of phenolic resin, 1.3 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0073] 2) adding 1 g of 50 nm silica crystals as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0074] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.1 wt %, the content of B element is 2.9 wt %; and the molar ratio of B element to N element is 1:3.7;

[0075] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, and finally calcining the mixture at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0076] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0077] In the Raney nickel composite material of Example 3, the content of Raney nickel is 13.2 wt %.

[0078] Application Example 3

[0079] The Raney nickel composite material obtained in Example 3 was placed in an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60°C, a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0080] Example 4

[0081] 1) 5 g of phenolic resin, 1.3 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0082] 2) adding 1 g of 500 nm silica crystals as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0083] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.2 wt %, the content of B element is 2.6 wt %; and the molar ratio of B element to N element is 1:3.7;

[0084] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, and finally calcining the mixture at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0085] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0086] In the Raney nickel composite material of Example 4, the content of Raney nickel is 13.2 wt %.

[0087] Application Example 4

[0088] The Raney nickel composite material obtained in Example 4 was placed in an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60° C., a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0089] Example 5

[0090] 1) 5 g of phenolic resin, 1.3 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0091] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0092] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 700° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.3 wt %, the content of B element is 3.4 wt %; and the molar ratio of B element to N element is 1:3.7;

[0093] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, and finally calcining the mixture at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0094] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0095] In the Raney nickel composite material of Example 5, the content of Raney nickel is 13.3 wt %.

[0096] Application Example 5

[0097] The Raney nickel composite material obtained in Example 5 was placed in an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60°C, a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0098] Example 6

[0099] 1) 5 g of phenolic resin, 1.3 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0100] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0101] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.1 wt %, the content of B element is 3.2 wt %; and the molar ratio of B element to N element is 1:3.7;

[0102] 4) adding 0.13 g of nickel chloride and 0.26 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding for 2 h, and finally calcining at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0103] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0104] In the Raney nickel composite material of Example 6, the content of Raney nickel is 12.9 wt %.

[0105] Application Example 6

[0106] The Raney nickel composite material obtained in Example 6 was placed in an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60° C., a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0107] Example 7

[0108] 1) 5 g of phenolic resin, 1.3 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0109] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0110] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.0 wt %, the content of B element is 3.1 wt %; and the molar ratio of B element to N element is 1:3.7;

[0111] 4) adding 0.13 g of nickel chloride and 0.07 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, and finally calcining the mixture at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0112] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0113] In the Raney nickel composite material of Example 7, the content of Raney nickel is 13.5 wt %.

[0114] Application Example 7

[0115] The Raney nickel composite material obtained in Example 7 was placed in an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60° C., a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0116] Example 8

[0117] 1) 5 g of phenolic resin, 1.3 g of boric acid, 1.7 g of melamine, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0118] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0119] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 6.9 wt %, the content of B element is 3.3 wt %; and the molar ratio of B element to N element is 1:3.7;

[0120] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, and finally calcining the mixture at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0121] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 1 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0122] In the Raney nickel composite material of Example 8, the content of Raney nickel is 12.8 wt %.

[0123] Application Example 8

[0124] The Raney nickel composite material obtained in Example 5 was placed in an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60°C, a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0125] Example 9

[0126] 1) Add 5 g of polyvinyl pyrrolidone, 1.3 g of boric acid, 5.1 g of urea, and 0.2 g of nickel nitrate hexahydrate to a mixed solution of 10 mL of ethanol and 20 mL of water and stir for 1 hour to obtain a uniform solution;

[0127] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0128] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 6.9 wt %, the content of B element is 2.9 wt %; and the molar ratio of B element to N element is 1:3;

[0129] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, followed by calcination at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0130] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0131] In the Raney nickel composite material of Example 9, the content of Raney nickel is 12.8 wt %.

[0132] Application Example 9

[0133] The Raney nickel composite material obtained in Example 9 was placed in an autoclave, and ethanol was used as the solution. Nitrobenzene was hydrogenated to produce aniline at a temperature of 60°C, a reaction pressure of 0.8 MPa hydrogen, and a mass ratio of nitrobenzene to catalyst of 40:1 for 0.5 h. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0134] Example 10

[0135] 1) 5 g of phenolic resin, 2.6 g of phenylboric acid, 1.7 g of melamine, and 0.09 g of nickel chloride were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0136] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0137] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 6.8 wt %, the content of B element is 2.7 wt %; and the molar ratio of B element to N element is 1:3.7;

[0138] 4) adding 0.13 g of nickel chloride and 0.13 g of aluminum chloride to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, followed by calcination at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0139] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0140] In the Raney nickel composite material of Example 10, the content of Raney nickel is 13.2 wt %.

[0141] Application Example 10

[0142] The Raney nickel composite material obtained in Example 10 was placed in an autoclave, and ethanol was used as the solution. Nitrobenzene was hydrogenated to produce aniline at a temperature of 60°C, a reaction pressure of 0.8 MPa hydrogen, and a mass ratio of nitrobenzene to catalyst of 40:1 for 0.5 h. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0143] Example 11

[0144] 1) 5 g of phenolic resin, 1.3 g of boric acid, 5.1 g of urea, and 0.2 g of nickel nitrate hexahydrate were added to a mixed solution of 10 mL of ethanol and 20 mL of water and stirred for 1 hour to obtain a uniform solution;

[0145] 2) adding 1 g of silica crystals with a particle size of 100 nm as a hard template to the solution obtained in step 1) and stirring for 2 h to obtain a uniform mixture;

[0146] 3) drying the mixture obtained in step 2) at 80° C. for 8 h to obtain a hard template wrapped by a porous carbon precursor; calcining the hard template wrapped by the porous carbon precursor at 850° C. for 3 h under a nitrogen atmosphere to obtain a hard template wrapped by a porous carbon; the content of Ni element in the porous carbon is 7.0 wt %, the content of B element is 2.9 wt %; and the molar ratio of B element to N element is 1:3;

[0147] 4) adding 0.13 g of nickel chloride and 0.21 g of aluminum acetate to 0.52 g of the porous carbon-coated hard template obtained in step 3) and grinding the mixture for 2 h, followed by calcination at 300° C. under a nitrogen atmosphere for 2 h to obtain a Raney nickel composite material precursor;

[0148] 5) All the Raney nickel composite material precursors obtained in step 4) were added to a 5 mol / L sodium hydroxide solution and subjected to superalkaline etching for 12 h to obtain a Raney nickel composite material. The specific surface area results are shown in Table 1.

[0149] In the Raney nickel composite material of Example 11, the content of Raney nickel is 13.3 wt %.

[0150] Application Example 11

[0151] The Raney nickel composite material obtained in Example 11 was placed in an autoclave and subjected to hydrogenation of nitrobenzene to produce aniline at 60°C, a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1 for 0.5 h using ethanol as the solution. The liquid was collected and analyzed by gas chromatography. The results are shown in Table 2.

[0152] Comparative Example 1

[0153] Raney nickel is obtained by alloying 1 mol of pure nickel metal with 1 mol of pure aluminum metal at 1500°C and then treating with 5 mol / L sodium hydroxide. Its specific surface area is shown in Table 1.

[0154] Comparative Application Example 1

[0155] The Raney nickel obtained in Comparative Example 1 was charged into an autoclave, and ethanol was used as the solution. The reaction was carried out for 0.5 h at a temperature of 60°C, a hydrogen pressure of 0.8 MPa, and a mass ratio of nitrobenzene to catalyst of 40:1. Nitrobenzene was then hydrogenated to produce aniline. The liquid was collected and analyzed by gas chromatography, as shown in Table 2. Stability tests are shown in Table 3 (the catalyst was recovered and reused in the reaction).

[0156] Table 1 Specific surface area of ​​the Raney nickel composite materials of Examples 1 to 11 and the Raney nickel of Comparative Example 1

[0157] sample <![CDATA[Specific surface area m 2 / g]]> Comparative Example 1 98.3 Example 1 893.5 Example 2 874.7 Example 3 1012.4 Example 4 682.6 Example 5 823.8 Example 6 735.1 Example 7 683.8 Example 8 468.2 Example 9 884.6 Example 10 892.4 Example 11 902.4

[0158] As shown in Table 1, the Raney nickel with a carrier has a higher specific surface area, and a suitable silica size is beneficial to promoting the specific surface area.

[0159] Table 2 Conversion rate of nitrobenzene in Application Examples 1 to 11 and Comparative Application Example 1

[0160]

[0161]

[0162] As shown in Table 2, the catalyst with the support has a higher nitrobenzene conversion rate than pure Raney nickel (Comparative Example 1), indicating that it has better catalytic activity.

[0163] Table 3 Conversion rate of nitrobenzene in Application Example 1 and Comparative Application Example 1

[0164] Number of times catalyst is used Comparative Example 1 (Conversion Rate %) Example 1 (Conversion %) 1 64.6 99.5 2 63.4 99.1 3 65.3 99.6 4 60.1 98.9 5 53.1 99.1 6 48.1 98.6 7 40.3 99.5 8 37.5 98.5 9 30.7 98.7 10 30.1 98.8

[0165] As shown in Table 3, the stability of the catalyst with a support is better than that of the catalyst without a support. Although the above embodiment describes the present invention in detail, it is only a part of the embodiment of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without inventiveness, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A Raney nickel composite material, characterized in that The invention comprises a carrier and Raney nickel loaded on the carrier; the carrier is porous carbon co-doped with Ni, B and N; the molar ratio of B to N is 1:1-5; The preparation method of the Raney nickel composite material comprises the following steps: A carbon-containing polymer, a boron-containing compound, a nitrogen-containing compound, and a first nickel salt are loaded onto a hard template by an impregnation method to obtain a hard template wrapped with a porous carbon precursor; the ratio of the amount of the B element in the boron-containing compound to the amount of the N element in the nitrogen-containing compound is 1:1 to 8.5; and the hard template comprises one of silicon dioxide crystals, sodium chloride, calcium carbonate, and magnesium oxide; calcining the hard template wrapped by the porous carbon precursor to obtain a hard template wrapped by the porous carbon precursor; The porous carbon-wrapped hard template is mixed with a second nickel salt and an aluminum salt and then subjected to a second calcination to generate a nickel-aluminum alloy. obtaining a Raney nickel composite material precursor; The Raney nickel composite material precursor is etched to remove the hard template agent to obtain the Raney nickel composite material.

2. The Raney nickel composite material according to claim 1, characterized in that The content of Raney nickel in the Raney nickel composite material is 6-20 wt %.

3. The Raney nickel composite material according to claim 1 or 2, characterized in that The content of Ni element in the carrier is 3-15 wt%.

4. The Raney nickel composite material according to claim 1 or 2, characterized in that The content of B element in the carrier is 1-5 wt%.

5. The Raney nickel composite material according to claim 1 or 2, characterized in that The specific surface area of ​​the Raney nickel composite material is 468.2 to 1012.4 m 2 / g.

6. The method for preparing the Raney nickel composite material according to any one of claims 1 to 5, characterized in that: The following steps are involved: A carbon-containing polymer, a boron-containing compound, a nitrogen-containing compound, and a first nickel salt are loaded onto a hard template by an impregnation method to obtain a hard template wrapped with a porous carbon precursor; the ratio of the amount of the B element in the boron-containing compound to the amount of the N element in the nitrogen-containing compound is 1:1 to 8.5; and the hard template comprises one of silicon dioxide crystals, sodium chloride, calcium carbonate, and magnesium oxide; calcining the hard template wrapped by the porous carbon precursor to obtain a hard template wrapped by the porous carbon precursor; The porous carbon-wrapped hard template is mixed with a second nickel salt and an aluminum salt and then subjected to a second calcination to generate a nickel-aluminum alloy. obtaining a Raney nickel composite material precursor; The Raney nickel composite material precursor is etched to remove the hard template agent to obtain the Raney nickel composite material.

7. The preparation method according to claim 6, characterized in that The mass ratio of the boron-containing compound to the first nickel salt is 2 to 5:1; the boron-containing compound comprises one of boric acid, phenylboric acid, p-aminophenylboric acid and 2-naphthaleneboric acid; The first nickel salt comprises one of nickel nitrate hexahydrate, nickel chloride, nickel acetate, nickel phosphate and nickel acetylacetonate; The nitrogen-containing compound includes one of urea, melamine, cyanamide and dicyandiamide.

8. The preparation method according to claim 6 or 7, characterized in that The mass ratio of the carbon-containing polymer to the first nickel salt is 10 to 30:1; the carbon-containing polymer comprises one of polyether, phenolic resin and polyvinyl pyrrolidone; The mass ratio of the first nickel salt to the hard template is 0.05-0.8:

1.

9. The preparation method according to claim 6 or 7, characterized in that: The mass ratio of the porous carbon-wrapped hard template to the second nickel salt is 1 to 8:1; The second nickel salt includes one of nickel nitrate hexahydrate, nickel chloride, nickel acetate, nickel phosphate and nickel acetylacetonate.

10. Use of the Raney nickel composite material according to any one of claims 1 to 5 or the Raney nickel composite material prepared by the preparation method according to any one of claims 6 to 9 as a catalyst in the hydrogenation of nitro compounds to prepare amine compounds.

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