High-entropy alloy material, preparation method and application thereof, and regeneration method

Abstract

The application provides a high-entropy alloy material and a preparation method and application and a regeneration method thereof, and belongs to the technical field of alloy materials.The carrier, non-ionic surfactant, metal salt and ionic liquid type reducing agent are mixed to carry out a reduction reaction to obtain the high-entropy alloy material; the reduction reaction comprises repeatedly carrying out heating and cooling; the heating is heating to 500-3500 DEG C, and the heating rate is 20-60 DEG C / min; the cooling is cooling to -30-40 DEG C, and the cooling rate is 20-60 DEG C / min; and the time of the reduction reaction is 1-15 h.Through controlling the heating and cooling rates, the degree of disorder of the high-entropy alloy material is improved, the mixing of the metal elements is more uniform, the simple crystal structure between the metal elements is promoted, and the catalytic activity of the high-entropy alloy material can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of alloy materials, and particularly relates to a high-entropy alloy material and a preparation method, application and regeneration method thereof. BACKGROUND

[0002] High-entropy alloys (HEAs) are a multi-component alloy system based on the composition design of new alloys maximizing entropy. Compared with traditional alloys, they have a series of unique mechanical properties. Recent studies have shown that HEAs have very high thermal stability, excellent fatigue resistance, wear resistance and corrosion resistance, and higher hardness, as well as excellent high-temperature and low-temperature performance compared with traditional alloys. However, the preparation process of the high-entropy alloy is complex at present, which is not suitable for industrialization popularization and application, and the catalytic performance is limited; and the high-entropy alloy catalyst in the prior art still contains a large amount of noble metal components, and the price is still high, and the cost cannot be effectively controlled. SUMMARY

[0003] Therefore, the purpose of the present application is to provide a high-entropy alloy material and a preparation method, application and regeneration method thereof. The preparation method provided by the present application is simple, and the high-entropy alloy material prepared by the method has high catalytic activity and low cost when used as a catalyst for catalyzing the hydrogenation of nitrobenzene to aniline.

[0004] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0005] The present application provides a preparation method of a high-entropy alloy material, comprising the following steps:

[0006] mixing the carrier, the non-ionic surfactant, the metal salt and the ionic liquid type reducing agent to perform a reduction reaction to obtain the high-entropy alloy material;

[0007] The metal elements in the metal salt include five or more of Ru, Co, Mo, Ni, Cu, In, Sn and Ga;

[0008] The reduction reaction comprises repeatedly raising and lowering the temperature; the temperature is raised to 500-3500 DEG C, and the rate of the temperature raising is 20-60 DEG C / min; the temperature is lowered to -30-40 DEG C, and the rate of the temperature lowering is 20-60 DEG C / min; and the time of the reduction reaction is 1-15 h.

[0009] Preferably, the carrier comprises cordierite; the non-ionic surfactant comprises polyethylene glycol, polyvinylpyrrolidone, an adduct of polypropylene glycol and ethylene oxide, or a polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer; and the ionic liquid type reducing agent comprises a quaternary ammonium salt ionic liquid or an imidazole salt ionic liquid.

[0010] Preferably, the quaternary ammonium salt ionic liquid comprises hexadecyl trimethyl ammonium bromide, didecyl dimethyl ammonium bromide or dioctyl dimethyl ammonium bromide; the imidazole salt ionic liquid comprises 1-butyl-3-methyl imidazole proline salt, 1-alkyl-3-methyl imidazole threonine salt, 1-alkyl-3-methyl imidazole methionine salt, 1-hexyl-3-methyl imidazole tryptophan or 1-alkyl-3-methyl imidazole tetrafluoroborate.

[0011] Preferably, the mass ratio of the carrier to the non-ionic surfactant is 1:(1-10); the mass ratio of the total mass of the carrier and the non-ionic surfactant to the metal salt is 1:(0.1-3); the mass ratio of the ionic liquid reducing agent to the total mass of the carrier, the non-ionic surfactant and the metal salt is 1:(1-9).

[0012] Preferably, when the metal salt contains Ru element, the mole fraction of Ru element is 1 part; when containing Co element, the mole fraction of Co element is 1-9 parts; when containing Mo element, the mole fraction of Mo element is 1-9 parts; when containing Ni element, the mole fraction of Ni element is 1-9 parts; when containing Cu element, the mole fraction of Cu element is 1-9 parts; when containing In element, the mole fraction of In element is 1 part; when containing Sn element, the mole fraction of Sn element is 1-9 parts; when containing Ga element, the mole fraction of Ga element is 1-9 parts.

[0013] The application provides a high-entropy alloy material prepared by the preparation method, which comprises a carrier and a high-entropy alloy dispersed in the carrier, and the high-entropy alloy comprises five or more alloy elements selected from Ru, Co, Mo, Ni, Cu, In, Sn and Ga.

[0014] The application provides an application of the high-entropy alloy material as a catalyst in catalyzing nitrobenzene hydrogenation to prepare aniline.

[0015] The application provides a regeneration method of the high-entropy alloy material, which comprises the following steps:

[0016] The quaternary ammonium salt ionic liquid or the imidazole salt ionic liquid is mixed with the deactivated high-entropy alloy material, calcination is carried out, and then reduction is carried out in a hydrogen atmosphere.

[0017] Preferably, the mass ratio of the quaternary ammonium salt ionic liquid or the imidazole salt ionic liquid to the deactivated high-entropy alloy material is 1:(1-9).

[0018] Preferably, the calcination temperature is 300-900 DEG C, and the time is 2-9 h; the reduction temperature is 100-400 DEG C, and the time is 1-6 h.

[0019] The application provides a preparation method of a high-entropy alloy material, comprising the following steps: mixing a carrier, a non-ionic surfactant, a metal salt and an ionic liquid type reducing agent, and performing a reduction reaction to obtain the high-entropy alloy material; the metal elements in the metal salt include five or more than five of Ru, Co, Mo, Ni, Cu, In, Sn and Ga; the reduction reaction comprises repeatedly performing temperature rising and temperature falling; the temperature rising is rising to 500-3500 DEG C, and the temperature rising rate is 20-60 DEG C / min; the temperature falling is falling to-30-40 DEG C, and the temperature falling rate is 20-60 DEG C / min; and the time of the reduction reaction is 1-15 h. The application controls the temperature rising and temperature falling rates, improves the confusion degree of the high-entropy alloy material, makes the metal mixing more uniform, promotes the formation of simple crystal structures among the metal elements, and can improve the catalytic activity of the high-entropy alloy material.

[0020] The preparation method provided by the application is simple and easy to realize industrial production. The preparation method provided by the application does not need to add too much noble metal component, and therefore the cost is low.

[0021] The high-entropy alloy material provided by the application has high catalytic activity and high target product selectivity in catalyzing the hydrogenation of nitrobenzene to aniline, and the catalytic process does not need to add sulfuric acid solution, and therefore the problem of large waste liquid amount does not exist.

[0022] The application provides a regeneration method of a high-entropy alloy material, comprising the following steps: mixing a quaternary ammonium salt type ionic liquid or an imidazole salt type ionic liquid with the deactivated high-entropy alloy material, performing calcination, and then reducing in a hydrogen atmosphere. The application removes the poisoned substances in the high-entropy alloy through calcination, and then activates the high-entropy alloy by passing hydrogen, so that the high-entropy alloy material restores the activity. DETAILED DESCRIPTION

[0023] The application provides a preparation method of a high-entropy alloy material, comprising the following steps:

[0024] Mixing a carrier, a non-ionic surfactant, a metal salt and an ionic liquid type reducing agent, and performing a reduction reaction to obtain the high-entropy alloy material.

[0025] In the present application, the metal elements in the metal salt include five or more of Ru, Co, Mo, Ni, Cu, In, Sn and Ga; in specific embodiments of the present application, specifically Ru, Co, Mo, Ni and Sn; Ru, Co, Mo, Ni and Cu; In, Co, Ga, Ni and Sn. In the present application, when the metal salt contains Ru element, the mole fraction of Ru element is preferably 1 part; when it contains Co element, the mole fraction of Co element is preferably 1-9 parts, further preferably 1-5 parts, more preferably 1.5-4 parts; when it contains Mo element, the mole fraction of Mo element is preferably 1-9 parts, further preferably 1-5 parts, more preferably 1.5-4 parts; when it contains Ni element, the mole fraction of Ni element is preferably 1-9 parts, further preferably 1-5 parts, more preferably 1.5-4 parts; when it contains Cu element, the mole fraction of Cu element is preferably 1-9 parts, further preferably 1-5 parts, more preferably 1.5-4 parts; when it contains In element, the mole fraction of In element is preferably 1 part; when it contains Sn element, the mole fraction of Sn element is preferably 1-9 parts, further preferably 1-5 parts, more preferably 1.5-4 parts; when it contains Ga element, the mole fraction of Ga element is preferably 1-9 parts, further preferably 1-5 parts, more preferably 1.5-4 parts.

[0026] In the present application, when the metal elements in the metal salt include Ru, the metal salt preferably includes ruthenium trichloride, ruthenium iodide or ammonium chlororuthenate; when the metal elements in the metal salt include Co, the metal salt preferably includes cobalt nitrate or cobalt acetate; when the metal elements in the metal salt include Mo, the metal salt preferably includes ammonium molybdate, molybdenum pentachloride or lithium molybdate; when the metal elements in the metal salt include Ni, the metal salt preferably includes nickel acetate, nickel chloride or nickel ammonium sulfate; when the metal elements in the metal salt include Cu, the metal salt preferably includes copper nitrate, copper chloride or copper sulfate; when the metal elements in the metal salt include In, the metal salt preferably includes indium chlorate or indium nitrate; when the metal elements in the metal salt include Sn, the metal salt preferably includes stannous sulfate or stannous chloride; when the metal elements in the metal salt include Ga, the metal salt preferably includes gallium nitrate, gallium chloride or gallium sulfate.

[0027] In the present application, the carrier preferably comprises cordierite; the non-ionic surfactant preferably comprises polyethylene glycol, polyvinylpyrrolidone (PVP), polypropylene glycol and ethylene oxide adduct (F127), or polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer (P123). In the present application, the ionic liquid reducing agent preferably comprises quaternary ammonium salt ionic liquid or imidazole salt ionic liquid; the quaternary ammonium salt ionic liquid preferably comprises cetyltrimethylammonium bromide, didecyldimethylammonium bromide, or dioctyl dimethyl ammonium bromide; the imidazole salt ionic liquid preferably comprises 1-butyl-3-methyl imidazole proline salt, 1-alkyl-3-methyl imidazole threonine salt, 1-alkyl-3-methyl imidazole methionine salt, 1-hexyl-3-methyl imidazole tryptophan, or 1-alkyl-3-methyl imidazole tetrafluoroborate.

[0028] In the present application, the mass ratio of the carrier to the non-ionic surfactant is preferably 1:(1-10), further preferably 1:(1-5), and more preferably 1:(1-3); the total mass of the carrier and the non-ionic surfactant to the mass of the metal salt is preferably 1:(0.1-3), further preferably 1:(0.1-1), and more preferably 1:(0.3-0.8); the mass of the ionic liquid reducing agent to the total mass of the carrier, the non-ionic surfactant, and the metal salt is preferably 1:(1-9), further preferably 1:(2-7), and more preferably 1:(3-6). In the present application, the carrier can promote the dispersion of the high-entropy alloy material and prevent its agglomeration; the non-ionic surfactant can enhance the stability of the high-entropy alloy material and promote its dispersion; the ionic liquid reducing agent of the present application also has a dispersing effect, and the reducing gas produced after heating can reduce the metal salt.

[0029] In the present application, the carrier, the non-ionic surfactant, the metal salt, and the ionic liquid reducing agent are mixed, preferably comprising mixing the carrier and the non-ionic surfactant to obtain a first mixture; mixing the first mixture and the metal salt to obtain a second mixture; mixing the second mixture and the ionic liquid reducing agent.

[0030] In the present application, the carrier and the non-ionic surfactant are mixed to obtain a first mixture.

[0031] In the present application, before mixing the carrier and the non-ionic surfactant, it is also preferable to include soaking the carrier in a hydrochloric acid solution and washing with deionized water.

[0032] In the present application, the concentration of the hydrochloric acid solution is preferably 5-35%, further preferably 15-25%, and more preferably 17-23%; the soaking time is preferably 10-80 min, further preferably 20-60 min, and more preferably 30-50 min; and the soaking temperature is preferably 20-70℃, further preferably 30-50℃, and more preferably 35-45℃. In the present application, there is no special requirement for the amount of the hydrochloric acid solution, which can only be used to immerse the carrier. In the present application, the carrier is immersed in the hydrochloric acid solution, which can clean the impurities on the surface of the carrier and increase its specific surface area and porosity.

[0033] In the present application, the washing with the deionized water is preferably performed until the pH value of the washing liquid is 7-9, and further preferably 7-8. In the present application, the pH value of the washing liquid is controlled to be 7-9, which can avoid the influence of the acidic condition on the mixing of the carrier and the metal salt.

[0034] After obtaining the first mixture, the present application mixes the first mixture with a metal salt to obtain a second mixture.

[0035] In the present application, the metal salt is preferably mixed with the first mixture in the form of a metal salt solution, and the present application has no special requirement for the concentration and preparation process of the metal salt solution, which can be prepared by using the concentration and preparation process known in the art. In the present application, when the metal salt is used in the form of a metal salt solution, the drying is further included after mixing with the first mixture. In the present application, the drying time is preferably 1-10 h, further preferably 2-8 h, and more preferably 3-6 h; and the drying temperature is preferably 50-200℃, further preferably 80-150℃, and more preferably 90-130℃.

[0036] After obtaining the second mixture, the present application mixes the second mixture with an ionic liquid-based reducing agent to perform a reduction reaction, thereby obtaining a high-entropy alloy material.

[0037] In the present application, the reduction reaction is preferably performed in a reactor filled with an inert gas; the inert gas preferably includes nitrogen or argon, and further preferably nitrogen. In the present application, the reduction reaction is preferably performed under the condition of constant oscillation; and the present application has no special requirement for the rate of the oscillation, which can be known in the art.

[0038] In the present application, the reduction reaction comprises repeatedly raising and lowering the temperature; the raising of the temperature is raising the temperature to 500-3500 DEG C, preferably 700-3000 DEG C, further preferably 1000-2500 DEG C; the rate of the raising of the temperature is 20-60 DEG C / min, preferably 25-55 DEG C / min, further preferably 30-45 DEG C / min; the lowering of the temperature is lowering the temperature to -30-40 DEG C, preferably -20-20 DEG C, further preferably -10-10 DEG C; the rate of the lowering of the temperature is 20-60 DEG C / min, preferably 25-55 DEG C / min, further preferably 30-45 DEG C / min; the time of the reduction reaction is 1-15 h, preferably 3-10 h, further preferably 4-8 h. The present application controls the rate of the raising and lowering of the temperature to improve the degree of disorder of the high-entropy alloy material, so that the metals are mixed more uniformly, promote the formation of simple crystal structures among the metal elements, and can improve the catalytic activity of the high-entropy alloy material.

[0039] The present application provides a high-entropy alloy material prepared by the preparation method described in the above scheme, comprising a carrier and a high-entropy alloy dispersed in the carrier, wherein the high-entropy alloy comprises five or more alloy elements selected from Ru, Co, Mo, Ni, Cu, In, Sn and Ga.

[0040] The present application provides an application of the high-entropy alloy material described in the above scheme as a catalyst in the catalytic hydrogenation of nitrobenzene to aniline.

[0041] In the present application, the catalytic hydrogenation of nitrobenzene to aniline preferably comprises the following steps: adding nitrobenzene and a catalyst into a reaction kettle, replacing the air in the reaction kettle with N2, then sealing the reaction kettle, introducing hydrogen, and performing catalytic hydrogenation to obtain aniline.

[0042] In the present application, HPLC is preferably used for quantitative analysis. The present application does not have special requirements for the conditions of the catalytic hydrogenation reaction, and the conditions well known in the art can be used. In the specific application examples of the present application, the temperature of the catalytic hydrogenation reaction is specifically 155 DEG C, the time is 2 h, the pressure of the hydrogen is 0.5 MPa, and the volume ratio of the nitrobenzene to the mass of the catalyst is 2 mL:0.4 g. In the present application, the catalytic hydrogenation reaction is preferably performed under stirring, and the stirring speed is preferably 1000 rpm.

[0043] The present application provides a regeneration method of the high-entropy alloy material described in the above scheme, comprising the following steps:

[0044] Mixing quaternary ammonium salt ionic liquid or imidazole salt ionic liquid with deactivated high-entropy alloy material, calcining, and then reducing in a hydrogen atmosphere.

[0045] In the present application, the mass ratio of the quaternary ammonium salt ionic liquid or imidazole salt ionic liquid to the deactivated high-entropy alloy material is preferably 1:(1-9), further preferably 1:(2-7), and more preferably 1:(3-6).

[0046] In the present application, the calcination temperature is preferably 300-900℃, further preferably 500-800℃, and more preferably 600-750℃; and the calcination time is preferably 2-9h, further preferably 3-5h, and more preferably 3.5-4.5h. In the present application, the reduction temperature is preferably 100-400℃, further preferably 200-300℃, and more preferably 250-280℃; and the reduction time is preferably 1-6h, further preferably 2-4h, and more preferably 2.5-3.5h. The present application can remove the toxic substances in the high-entropy alloy by calcination, and then activate the high-entropy alloy by hydrogen, so as to restore the activity of the high-entropy alloy material.

[0047] In order to further illustrate the present application, the high-entropy alloy material, the preparation method and application thereof, and the regeneration method provided by the present application are described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present application.

[0048] Example 1

[0049] 1g of cordierite was soaked in 10mL of a 25% concentration hydrochloric acid solution, the soaking temperature was 30℃, and the soaking time was 30min, then the sample was washed with deionized water until the pH value of the washing liquid was 7, and finally 2g of polyethylene glycol was added and mixed uniformly to obtain a first mixture;

[0050] The first mixture was mixed with metal salts (RuI3, (CH3CO2)2Co, (NH4)2MoO4, H8N2NiO8S2, and SnSO4 were mixed, and the metal molar ratio was Ru:Co:Mo:Ni:Sn=1:3:2:2:3) at a mass ratio of 1:0.5, and then dried at 110℃ for 6h to obtain a second mixture;

[0051] The second mixture was placed in a nitrogen-filled reactor, 1g of dioctyl dimethyl ammonium bromide was added, and oscillation was continuously performed, the temperature was rapidly raised to 2700℃ at a rate of 40℃ / min, then rapidly lowered to -10℃ at a rate of 40℃ / min, and the temperature was repeatedly raised and lowered and oscillation was continuously performed for 9h to obtain a high-entropy alloy material.

[0052] Application Example 1

[0053] The high-entropy alloy material of Example 1 is used as a catalyst, 2 mL of nitrobenzene and 0.4 g of the high-entropy alloy catalyst are added into a reaction kettle, the reaction kettle is sealed after the air in the reaction kettle is replaced by N2, H2 pressure of 0.5 MPa is introduced, heating is performed to a reaction temperature of 155 ℃, and stirring is performed at a speed of 1000 rpm for 2 h, to obtain aniline; the conversion rate is 98.3%, and the selectivity is 99.2%.

[0054] Catalyst deactivation and regeneration: 1 g of 1-butyl-3-methylimidazolium proline is added and mixed with 5 g of the deactivated high-entropy alloy catalyst, calcination is performed at a temperature of 800 ℃ for 4 h, and hydrogen reduction is performed at 250 ℃ for 3 h.

[0055] 2 mL of nitrobenzene and 0.4 g of the regenerated high-entropy alloy catalyst are added into a reaction kettle, the reaction kettle is sealed after the air in the reaction kettle is replaced by N2, H2 pressure of 0.5 MPa is introduced, heating is performed to a reaction temperature of 155 ℃, and stirring is performed at a speed of 1000 rpm for 2 h, to obtain aniline; the conversion rate is 98.4%, and the selectivity is 99.5%.

[0056] Example 2

[0057] 1 g of cordierite is soaked in 10 mL of a hydrochloric acid solution with a concentration of 20%, the soaking temperature is 30 ℃, the soaking time is 30 min, the cordierite is washed with deionized water until the pH value of the washing liquid is 7, and finally 1 g of polyethylene glycol is added and mixed uniformly, to obtain a first mixture;

[0058] The first mixture is mixed with a metal salt (RuCl3, Co(NO3)2·6H2O, (NH4)2MoO4, NiC4H6O4·4H2O and Cu(NO3)2 are mixed, and the molar ratio of the metals is Ru:Co:Mo:Ni:Cu = 1:2:1:1:1) at a mass ratio of 1:0.5, and then dried at 110 ℃ for 6 h, to obtain a second mixture;

[0059] The second mixture is placed in a nitrogen-filled reactor, 1 g of dioctyl dimethyl ammonium bromide is added and continuously oscillated, rapid heating to 2700 ℃ is performed at a rate of 40 ℃ / min, rapid cooling to 0 ℃ is performed at a rate of 40 ℃ / min, and the heating and cooling are repeatedly performed and continuously oscillated for 5 h, to obtain a high-entropy alloy material.

[0060] Application Example 2

[0061] The high-entropy alloy material of Example 2 was used as a catalyst, 2 mL of nitrobenzene and 0.4 g of the high-entropy alloy catalyst were added to a reaction kettle, the reaction kettle was sealed after being replaced with N2, H2 pressure of 0.5 MPa was introduced, heating was performed to a reaction temperature of 155 ℃, and stirring was performed at a speed of 1000 rpm for 2 h, to obtain aniline; the conversion rate was 80.9%, and the selectivity was 81.1%.

[0062] Catalyst deactivation and regeneration: 1 g of dioctyl dimethyl ammonium bromide was added and mixed with 5 g of the deactivated high-entropy alloy catalyst, calcination was performed at a temperature of 800 ℃ for 4 h, and hydrogen reduction was performed at 250 ℃ for 3 h.

[0063] 2 mL of nitrobenzene and 0.4 g of the regenerated high-entropy alloy catalyst were added to a reaction kettle, the reaction kettle was sealed after being replaced with N2, H2 pressure of 0.5 MPa was introduced, heating was performed to a reaction temperature of 155 ℃, and stirring was performed at a speed of 1000 rpm for 2 h, to obtain aniline; the conversion rate was 80.8%, and the selectivity was 81.6%.

[0064] Example 3

[0065] 1 g of cordierite was soaked in 10 mL of a 25% hydrochloric acid solution, the soaking temperature was 30 ℃, the soaking time was 30 min, deionized water was used for washing until the pH value of the washing liquid was 7, and finally 1 g of F127 was added and uniformly mixed, to obtain a first mixture;

[0066] The first mixture was mixed with a metal salt (RuI3, (CH3CO2)2Co, (NH4)2MoO4, H8N2NiO8S2 and CuSO4 were mixed, and the molar ratio of the metals was Ru:Co:Mo:Ni:Cu = 1:1:1:1:1) at a mass ratio of 1:0.5, and then dried at 110 ℃ for 6 h, to obtain a second mixture;

[0067] The second mixture was placed in a nitrogen-filled reactor, 1 g of 1-butyl-3-methyl imidazole proline salt was added, and oscillation was continuously performed, rapid heating to 2700 ℃ was performed at a rate of 40 ℃ / min, rapid cooling to -10 ℃ was performed at a rate of 40 ℃ / min, and the heating and cooling were repeatedly performed and oscillation was continuously performed for 9 h, to obtain a high-entropy alloy material.

[0068] Application Example 3

[0069] Take 2 mL of nitrobenzene, 0.4 g of high-entropy alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, and then seal the reaction kettle. The reaction kettle is connected to a hydrogen source with a pressure of 0.5 MPa. The reaction temperature is set to 155°C, and the stirring speed is set to 1000 rpm. After 2 hours of reaction, aniline is obtained. The conversion rate is 91.3%, and the selectivity is 92.2%.

[0070] Catalyst regeneration: Add 1 g of 1-butyl-3-methylimidazole proline salt to 5 g of deactivated high-entropy alloy catalyst and mix well. Calcine at 800°C for 4 hours, and then reduce at 250°C for 3 hours under hydrogen.

[0071] Take 2 mL of nitrobenzene, 0.4 g of regenerated high-entropy alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, and then seal the reaction kettle. The reaction kettle is connected to a hydrogen source with a pressure of 0.5 MPa. The reaction temperature is set to 155°C, and the stirring speed is set to 1000 rpm. After 2 hours of reaction, aniline is obtained. The conversion rate is 91.5%, and the selectivity is 91.2%.

[0072] Example 4

[0073] Soak 1 g of cordierite in 10 mL of 25% hydrochloric acid solution at 30°C for 30 minutes. Wash with deionized water until the pH of the washing solution is 7. Finally, mix 1 g of PEG evenly to obtain a first mixture.

[0074] Mix the first mixture with metal salts (mix RuI3, (CH3CO2)2Co, MoCl5, NiC4H6O4·4H2O, and Cu(NO3)2 with a metal molar ratio of Ru:Co:Mo:Ni:Cu = 1:1:2:1:1) at a mass ratio of 1:0.5. Dry at 110°C for 6 hours to obtain a second mixture.

[0075] Place the second mixture in a nitrogen-filled reactor and add 1 g of dioctyl dimethyl ammonium bromide while continuously oscillating. Rapidly heat to 2700°C at a rate of 40°C / min. Then rapidly cool to -10°C at a rate of 40°C / min. Repeat the heating and cooling and continuously oscillate for 9 hours to obtain a high-entropy alloy material.

[0076] Application Example 4

[0077] Take 2 mL of nitrobenzene, 0.4 g of regenerated high-entropy alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, then seal the reaction kettle, and then introduce H2 pressure of 0.5 MPa. Heat to a reaction temperature of 155°C, and then react for 2 h at a stirring speed of 1000 rpm. Aniline is obtained; the conversion rate is 85.3%, and the selectivity is 84.3%.

[0078] Catalyst deactivation and regeneration: 1 g of dioctyl dimethyl ammonium bromide is added and mixed with 5 g of deactivated high-entropy alloy catalyst, which is calcined at a temperature of 800°C for 4 h, and then reduced by hydrogen at 250°C for 3 h.

[0079] Take 2 mL of nitrobenzene, 0.4 g of regenerated high-entropy alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, then seal the reaction kettle, and then introduce H2 pressure of 0.5 MPa. Heat to a reaction temperature of 155°C, and then react for 2 h at a stirring speed of 1000 rpm. Aniline is obtained; the conversion rate is 85.3%, and the selectivity is 84.3%.

[0080] Example 5

[0081] Soak 1 g of cordierite in 10 mL of a 25% concentration hydrochloric acid solution, with a soaking temperature of 30°C and a soaking time of 30 min. Then wash with deionized water until the pH value of the washing liquid is 7. Finally, mix 2 g of polyethylene glycol to obtain a first mixture.

[0082] Mix the first mixture with metal salts (mix In(NO3)3, (CH3CO2)2Co, Ga2(SO4)3, H8N2NiO8S2, and SnSO4 with a metal molar ratio of In:Co:Ga:Ni:Sn = 1:3:2:2:3) at a mass ratio of 1:0.5, and then dry at 110°C for 6 h to obtain a second mixture.

[0083] Place the second mixture in a nitrogen-filled reactor, add 2 g of dioctyl dimethyl ammonium bromide, and continuously oscillate. Rapidly heat to 1500°C at a rate of 40°C / min, and then rapidly cool to -10°C at a rate of 40°C / min. Repeat the heating and cooling and continuously oscillate for 9 h to obtain a high-entropy alloy material.

[0084] Application Example 5

[0085] Take 2 mL of nitrobenzene, 0.4 g of regenerated high-entropy alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, then seal the reaction kettle, and then introduce H2 pressure of 0.5 MPa. Heat to a reaction temperature of 155°C, and then react for 2 h at a stirring speed of 1000 rpm. Aniline is obtained; the conversion rate is 85.3%, and the selectivity is 84.3%.

[0086] Catalyst regeneration after deactivation: 2 g of dioctyl dimethyl ammonium bromide was added and mixed with 5 g of the deactivated high-entropy alloy catalyst, calcination was performed at 800°C for 4 h, and then reduction was performed at 250°C for 3 h under hydrogen.

[0087] 2 mL of nitrobenzene and 0.4 g of the regenerated high-entropy alloy catalyst were added to a reaction kettle, the reaction kettle was sealed after the air in the reaction kettle was replaced with N2, H2 was introduced at a pressure of 0.5 MPa, heating was performed to a reaction temperature of 155°C, and reaction was performed at a stirring speed of 1000 rpm for 2 h, to obtain aniline; the conversion rate was 95.3%, and the selectivity was 95.2%.

[0088] Comparative Example 1

[0089] 1 g of cordierite was soaked in 10 mL of a 10% hydrochloric acid solution, the soaking temperature was 20°C, the soaking time was 60 min, then the cordierite was washed with deionized water until the pH value of the washing liquid was 7, and finally 2 g of PVP was added and mixed uniformly to obtain a first mixture;

[0090] The first mixture was mixed with a metal salt (RuCl3, NiC4H6O4·4H2O and Cu(NO3)2 were mixed, and the molar ratio of the metals was Ru:Ni:Cu = 1:1:2) at a mass ratio of 1:0.2, and then dried at 110°C for 6 h to obtain a second mixture;

[0091] The second mixture was placed in a nitrogen-filled reactor, 1 g of cetyltrimethylammonium bromide was added, and oscillation was continuously performed, rapid heating was performed to 1700°C at a rate of 40°C / min, rapid cooling was then performed to 0°C at a rate of 40°C / min, and the heating and cooling were repeatedly performed and oscillation was continuously performed for 6 h to obtain an alloy material.

[0092] Comparative Application Example 1

[0093] The alloy material of Comparative Example 1 was used as a catalyst, 2 mL of nitrobenzene and 0.4 g of the alloy catalyst were added to a reaction kettle, the reaction kettle was sealed after the air in the reaction kettle was replaced with N2, H2 was introduced at a pressure of 0.5 MPa, heating was performed to a reaction temperature of 155°C, and reaction was performed at a stirring speed of 1000 rpm for 2 h, to obtain aniline; the conversion rate was 78.4%, and the selectivity was 79.3%.

[0094] Catalyst regeneration after deactivation: 1 g of cetyltrimethylammonium bromide was added and mixed with 5 g of the deactivated alloy catalyst, calcination was performed at 800°C for 4 h, and then reduction was performed at 250°C for 3 h under hydrogen.

[0095] Take 2 mL of nitrobenzene, 0.4 g of the regenerated alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, seal the reaction kettle, and then add H2 to a pressure of 0.5 MPa. Heat to a reaction temperature of 155°C, and then react for 2 h at a stirring speed of 1000 rpm. Aniline is obtained. The conversion rate is 78.1%, and the selectivity is 78.2%.

[0096] Comparative Example 2

[0097] Soak 1 g of cordierite in 10 mL of a 30% hydrochloric acid solution at a soaking temperature of 60°C for 10 min. Then wash with deionized water until the pH value of the washing liquid is 7 to obtain treated cordierite.

[0098] Mix the treated cordierite with a metal salt (mix RuI3 and (CH3CO2)2Co, with a metal molar ratio of Ru:Co = 1:2) at a mass ratio of 1:0.5, and then dry at 110°C for 6 h to obtain a metal salt-cordierite mixture.

[0099] Place the metal salt-cordierite mixture in a nitrogen-filled reactor, add 1 g of dioctyl dimethyl ammonium bromide, and continuously oscillate. Rapidly heat to 1600°C at a heating rate of 40°C / min, and then rapidly cool to 10°C at a cooling rate of 40°C / min. Repeat the heating and cooling and continuously oscillate for 11 h to obtain an alloy material.

[0100] Comparative Example 2

[0101] Take 2 mL of nitrobenzene, 0.4 g of the alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, seal the reaction kettle, and then add H2 to a pressure of 0.5 MPa. Heat to a reaction temperature of 155°C, and then react for 2 h at a stirring speed of 1000 rpm. Aniline is obtained. The conversion rate is 66.9%, and the selectivity is 73.4%.

[0102] Catalyst deactivation and regeneration: mix 1 g of dioctyl dimethyl ammonium bromide with 5 g of the deactivated alloy catalyst, and then calcine at a temperature of 800°C for 4 h, and then reduce at a hydrogen gas temperature of 250°C for 3 h.

[0103] Take 2 mL of nitrobenzene, 0.4 g of the regenerated alloy catalyst into the reaction kettle, replace the air in the reaction kettle with N2, seal the reaction kettle, and then add H2 to a pressure of 0.5 MPa. Heat to a reaction temperature of 155°C, and then react for 2 h at a stirring speed of 1000 rpm. Aniline is obtained. The conversion rate is 60.2%, and the selectivity is 69.4%.

[0104] Comparative Example 3

[0105] 1 g of cordierite was soaked in 10 mL of 20% hydrochloric acid solution, the soaking temperature was 30°C, the soaking time was 30 min, and then the treated cordierite was washed with deionized water until the pH value of the washing liquid was 7;

[0106] The treated cordierite was mixed with metal salt (MoCl5, Cl2Ni and Cu(NO3)2 were mixed, and the molar ratio of metals was Mo:Ni:Cu = 1:2:2) at a mass ratio of 1:1.5, and then dried at 110°C for 6 h to obtain a metal salt-cordierite mixture;

[0107] The metal salt-cordierite mixture was placed in a nitrogen-filled reactor with 1 g of dioctyl dimethyl ammonium bromide and continuously oscillated, and then rapidly heated to 1800°C at a rate of 40°C / min, and then rapidly cooled to 0°C at a rate of 40°C / min. The heating and cooling were repeated and continuously oscillated for 5 h to obtain an alloy material.

[0108] Comparative Example 3

[0109] The alloy material of Comparative Example 3 was used as a catalyst, 2 mL of nitrobenzene and 0.4 g of the alloy catalyst were added to a reaction kettle, the reaction kettle was sealed after replacing the air in the reaction kettle with N2, H2 was introduced at a pressure of 0.5 MPa, and the temperature was heated to 155°C. After stirring at a speed of 1000 rpm for 2 h, aniline was obtained; the conversion rate was 79.9%, and the selectivity was 62.4%.

[0110] Catalyst deactivation and regeneration: 1 g of dioctyl dimethyl ammonium bromide was mixed with 5 g of deactivated alloy catalyst, and calcination was carried out at 800°C for 4 h, and then hydrogen reduction was carried out at 250°C for 3 h.

[0111] 2 mL of nitrobenzene and 0.4 g of the regenerated alloy catalyst were added to a reaction kettle, the reaction kettle was sealed after replacing the air in the reaction kettle with N2, H2 was introduced at a pressure of 0.5 MPa, and the temperature was heated to 155°C. After stirring at a speed of 1000 rpm for 2 h, aniline was obtained; the conversion rate was 77.9%, and the selectivity was 61.4%.

[0112] Comparative Example 4

[0113] 1 g of cordierite was soaked in 10 mL of 30% hydrochloric acid solution, the soaking temperature was 20°C, and the soaking time was 10 min, and then the treated cordierite was washed with deionized water until the pH value of the washing liquid was 7;

[0114] The treated cordierite was mixed with metal salt (NiC4H6O4·4H2O) at a mass ratio of 1:1, and then dried at 110°C for 6 h to obtain a metal salt-cordierite mixture;

[0115] The metal salt-coptis mixture is placed in a nitrogen-filled reactor, 1 g of cetyltrimethylammonium bromide is added and continuously shaken, and then rapidly heated to 1700°C at a rate of 40°C / min; then rapidly cooled to 0°C at a rate of 40°C / min; the heating and cooling are repeated and continuously shaken for 6 h to obtain a metal material.

[0116] Comparative Example 4

[0117] The metal material of Comparative Example 4 is used as a catalyst, 2 mL of nitrobenzene and 0.4 g of the metal catalyst are added to a reaction kettle, the reaction kettle is sealed after replacing the air in the reaction kettle with N2, H2 is introduced at a pressure of 0.5 MPa, heated to a reaction temperature of 155°C, and reacted for 2 h at a stirring speed of 1000 rpm to obtain aniline; the conversion rate is 68.4% and the selectivity is 55.2%.

[0118] Catalyst deactivation and regeneration: 1 g of cetyltrimethylammonium bromide is mixed with 5 g of the deactivated metal catalyst, calcined at a temperature of 800°C for 4 h, and then reduced at 250°C for 3 h.

[0119] 2 mL of nitrobenzene and 0.4 g of the regenerated metal catalyst are added to a reaction kettle, the reaction kettle is sealed after replacing the air in the reaction kettle with N2, H2 is introduced at a pressure of 0.5 MPa, heated to a reaction temperature of 155°C, and reacted for 2 h at a stirring speed of 1000 rpm to obtain aniline; the conversion rate is 55.4% and the selectivity is 53.2%. Table 1 is a summary of the conversion rate and selectivity data of the catalysts prepared in the examples and comparative examples.

[0120] Table 1 is a summary of the conversion rate and selectivity data of the catalysts prepared in the examples and comparative examples.

[0121]

[0122]

[0123] As can be seen from Table 1, the high-entropy alloy material prepared in the present application has high catalytic activity as a catalyst for the hydrogenation of nitrobenzene to aniline. Comparative Examples 1-4 do not meet the requirements of high-entropy alloy preparation because the number of metal types prepared does not reach five or more, so the conversion rate and selectivity of the catalyst prepared by simply adding one or two metals are low and the catalyst is easily deactivated. Examples 1-5 are deactivated after 8-10 uses; Comparative Example 1 is deactivated after 5 uses; Comparative Example 2 is deactivated after 5 uses; Comparative Example 3 is deactivated after 4 uses; and Comparative Example 4 is deactivated after 4 uses. The deactivation criterion is that the conversion rate or selectivity decreases to below 40%, which is considered to be deactivated.

[0124] Although the above embodiments have been described in detail, it should be understood that these are only some embodiments of the present application, but not all embodiments. Other embodiments can be obtained on the basis of the above embodiments without creativity, and these embodiments all belong to the protection scope of the present application.

Claims

1. A method for preparing a high-entropy alloy material, characterized in that, Includes the following steps: A high-entropy alloy material is obtained by mixing a carrier, a nonionic surfactant, a metal salt, and an ionic liquid reducing agent to carry out a reduction reaction. The metal salt contains five or more of the following metal elements: Ru, Co, Mo, Ni, Cu, In, Sn, and Ga. The reduction reaction includes: repeated heating and cooling; the heating is to raise the temperature to 500~3500℃ at a rate of 20~60℃ / min; the cooling is to lower the temperature to -30~40℃ at a rate of 20~60℃ / min; the reduction reaction takes 1~15 hours. The carrier includes cordierite; the nonionic surfactant includes polyethylene glycol, polyvinylpyrrolidone, an addition polymer of polypropylene glycol and ethylene oxide, or a poly(ethylene oxide-poly(propylene oxide-poly(ethylene oxide)) triblock copolymer. The ionic liquid reducing agents include quaternary ammonium salt ionic liquids or imidazole salt ionic liquids; The quaternary ammonium salt ionic liquids include hexadecyltrimethylammonium bromide, didecyldimethylammonium bromide, or dioctyldimethylammonium bromide; the imidazole salt ionic liquids include 1-butyl-3-methylimidazolium proline, 1-alkyl-3-methylimidazolium threonine, 1-alkyl-3-methylserine, 1-hexyl-3-methylimidazolium tryptophan, or 1-alkyl-3-methylimidazolium tetrafluoroborate.

2. The preparation method according to claim 1, characterized in that, The mass ratio of the carrier to the nonionic surfactant is 1:(1~10); the mass ratio of the total mass of the carrier and the nonionic surfactant to the metal salt is 1:(0.1~3); the mass ratio of the ionic liquid reducing agent to the total mass of the carrier, the nonionic surfactant and the metal salt is 1:(1~9).

3. The preparation method according to claim 1, characterized in that, When the metal salt contains Ru, the molar amount of Ru is 1 part; when it contains Co, the molar amount of Co is 1 to 9 parts; when it contains Mo, the molar amount of Mo is 1 to 9 parts; when it contains Ni, the molar amount of Ni is 1 to 9 parts; when it contains Cu, the molar amount of Cu is 1 to 9 parts; when it contains In, the molar amount of In is 1 part; when it contains Sn, the molar amount of Sn is 1 to 9 parts; when it contains Ga, the molar amount of Ga is 1 to 9 parts.

4. The high-entropy alloy material prepared by the preparation method according to any one of claims 1 to 3, characterized in that, It includes a support and a high-entropy alloy dispersed in the support, the high-entropy alloy including five or more alloying elements selected from Ru, Co, Mo, Ni, Cu, In, Sn and Ga.

5. The application of the high-entropy alloy material as described in claim 4 as a catalyst in the catalytic hydrogenation of nitrobenzene to aniline.

6. The method for regenerating high-entropy alloy materials according to claim 4, characterized in that, Includes the following steps: Quaternary ammonium salt ionic liquids or imidazole salt ionic liquids are mixed with deactivated high-entropy alloy materials, calcined, and then reduced in a hydrogen atmosphere.

7. The regeneration method according to claim 6, characterized in that, The mass ratio of the quaternary ammonium salt ionic liquid or imidazole salt ionic liquid to the deactivated high-entropy alloy material is 1:(1~9).

8. The regeneration method according to claim 6 or 7, characterized in that, The calcination temperature is 300~900℃ and the time is 2~9h; the reduction temperature is 100~400℃ and the time is 1~6h.

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