Preparation method of supported nickel-based catalyst and preparation of polyether amine by using same

Abstract

The application belongs to the technical field of fine chemical synthesis, and discloses a preparation method of a supported nickel-based catalyst and polyether amine prepared by using the same. The preparation method comprises the following steps: S1, using a first active metal source, aluminum hydroxide dry gel powder, a extrusion aid, a hole expanding agent and silica sol as raw materials, and adopting a kneading forming mode, an alumina carrier containing an active metal component is prepared; S2, an impregnation solution is prepared by using a second active metal source, then the alumina carrier prepared in the step S1 is impregnated, and then is calcined, so that a supported nickel-based catalyst is prepared; the first active metal source and the second active metal source both comprise a nickel source, a platinum source, a copper source and a cobalt source. The supported nickel-based catalyst prepared by the application has the characteristics of large pore volume, large specific surface area and uniform active component distribution; the polyether amine prepared by using the same can significantly improve polyol ether conversion rate and primary amine selectivity, and reduce the generation of by-products.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of fine chemical synthesis, and particularly relates to a preparation method of a supported nickel-based catalyst and preparation of polyetheramine by using the same. BACKGROUND

[0002] Polyetheramine (PEA) is a kind of compound with a soft polyether skeleton and an amino or amine group (generally a secondary amine group, a primary amine group or a polyamine group containing active hydrogen) at one end. As a functional chemical, it has important uses in many fields such as chemical industry and medicine. At present, the synthesis methods of polyetheramine mainly include catalytic amination method, leaving group method, hydrolysis method, aminophenoxy method, aminobutyrene ester method, cyanoalkylation method and the like. The catalytic amination method has the advantages of high raw material utilization rate, small environmental pollution, high conversion rate and good selectivity, easy separation and purification of the synthesized product, and high product purity. Moreover, the method only involves one-step reaction, and the process is simple. It is the first choice for large-scale industrial continuous production of foreign chemical companies at present. At present, polyetheramine products, especially low molecular weight polyetheramine products, are relatively short in supply, which to some extent restricts the wide application of polyetheramine products.

[0003] The hydrogenation ammination fixed bed catalysts currently in mature application can be roughly divided into three categories: copper-based catalysts, noble metal catalysts and nickel-based catalysts. The preparation processes can be roughly divided into two categories: co-precipitation and impregnation. The co-precipitation method is also a widely used preparation process for polyetheramine catalysts. It is a method of adding a precipitant to a mixed metal salt solution to precipitate two or more cations in the solution together to form a precipitate mixture or solid solution precursor, and then filtering, washing and heat decomposing to obtain a composite oxide. However, the properties of the precipitate largely determine the properties of the catalyst, and various factors need to be carefully determined and strictly controlled, which requires high operating skills. A large amount of alkali is consumed during the synthesis process, and the influencing factors are complex, requiring efficient washing and filtering devices, and generating a large amount of wastewater. At the same time, when the bulk catalyst prepared by co-precipitation meets the mechanical strength requirements for use, the surface active site density is low, which cannot fully utilize the advantages of high content of active metal components, reduces the utilization rate of active metals, and increases the preparation cost of the catalyst.

[0004] Therefore, the currently used polyether amine synthesis catalyst is generally obtained by impregnation. The specific steps are mainly as follows: first, an alumina carrier is prepared, then active components such as Ni and Co are impregnated on the carrier, and finally the catalyst is obtained by drying and calcination, but the pore volume and specific surface area of the catalyst are lost to a certain extent due to the two drying and calcination (the carrier also undergoes one drying and calcination during the preparation of the shaped carrier), so that the process is relatively complex and the cost of the catalyst is relatively high. It is well known that the impregnation method is based on the impregnation of active components in the form of salt solution on the porous carrier and penetration to the inner surface. Due to the limitations of this method, the loading capacity of the active components is limited, and the activity of the catalyst cannot be improved. Industrial catalyst development should consider cost, time and energy consumption, and the coupling of the supporting process with the shaping process to prepare shaped catalysts will be a good solution to this problem. The traditional dry mixing method for preparing catalysts is to prepare catalysts by mixing, kneading, shaping, drying and calcination of active components and carrier precursors and binders. The catalysts prepared by the dry mixing method in industry generally have the problems of uneven dispersion of active components and poor catalyst strength. Therefore, it is of great significance to study new catalyst preparation technologies for reducing the production cost of catalysts and improving the activity of catalysts. SUMMARY

[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a preparation method of a supported nickel-based catalyst and the preparation of polyether amine using the same. The supported nickel-based catalyst prepared by the present application has high activity and low cost. The use of the same to prepare polyether amine can significantly improve the conversion rate of polyol ether and the selectivity of primary amine, and reduce the production of by-products.

[0006] The present application provides a preparation method of a supported nickel-based catalyst.

[0007] Specifically, the present application provides a preparation method of a supported nickel-based catalyst, which comprises the following steps:

[0008] S1, using a first active metal source, aluminum hydroxide dry gel powder, a extrusion aid, a pore expanding agent and silica sol as raw materials, an alumina carrier containing active metal components is prepared by kneading and shaping;

[0009] S2, an impregnation solution is prepared by using a second active metal source, then the alumina carrier prepared in step (1) is impregnated, and then calcined to obtain a supported nickel-based catalyst;

[0010] In steps S1 and S2, the first active metal source and the second active metal source both include a nickel source, a platinum source, a copper source and a cobalt source. The first active metal source and the second active metal source include but are not limited to nitrate, sulfate, organic salt, chloride and the like of the above-mentioned metals, and are preferably nitrate of the above-mentioned metals.

[0011] Preferably, in the first active metal source, the molar ratio of nickel, platinum, copper, cobalt in the nickel source, the platinum source, the copper source and the cobalt source is 1:(0.0008-0.002):(0.06-0.08):(0.05-0.2).

[0012] Preferably, in the second active metal source, the molar ratio of nickel, platinum, copper, cobalt in the nickel source, the platinum source, the copper source and the cobalt source is 1:(0.0008-0.002):(0.06-0.08):(0.05-0.2).

[0013] In steps S1 and S2, the first active metal source and the second active metal source also independently comprise at least one of a zirconium source, a lanthanum source, a rhenium source.

[0014] The preparation process of step S1 includes any one of the following two ways:

[0015] (1) Dissolve the first active metal source in water to prepare a kneading solution; take the aluminum hydroxide dry gel powder, add a extrusion aid, a pore-expanding agent and a silica sol, mix uniformly, then add the kneading solution for kneading, and then prepare an alumina carrier containing an active metal component through molding, drying and calcination;

[0016] (2) Dissolve the first active metal source in water, add a silica sol to prepare a kneading solution; take the aluminum hydroxide dry gel powder, add an extrusion aid and a pore-expanding agent, mix uniformly, then add the kneading solution for kneading, and then prepare an alumina carrier containing an active metal component through molding, drying and calcination.

[0017] In the process of kneading and molding, the silica sol can be added in two ways: one is to first add the silica sol to the aluminum hydroxide dry gel powder mixed with the extrusion aid and the pore-expanding agent, mix uniformly, and then add the kneading solution; the second method is to first mix and dissolve the silica sol with the first active metal source, and then add the aluminum hydroxide dry gel powder mixed with the extrusion aid and the pore-expanding agent. From the effect, the carrier prepared by the first way has more excellent pore structure.

[0018] Preferably, the silica sol includes an alkaline silica sol or an acidic silica sol.

[0019] Preferably, the extrusion aid includes at least one of pearl millet powder, starch, cellulose, carbon powder.

[0020] Preferably, the amount of the extrusion aid added is 1%-30% of the mass of the aluminum hydroxide dry gel powder; further preferably, the amount of the extrusion aid added is 3%-15% of the mass of the aluminum hydroxide dry gel powder, 5%, 6%, 8%, 10%, 12%, etc.

[0021] Preferably, the pore-expanding agent is carbon black. In the process of shaping, the carbon black as pore-expanding agent is beneficial to the pore-expanding of the carrier and the improvement of the pore distribution concentration.

[0022] Preferably, the pore-expanding agent is added in an amount of 1% to 30% by mass of the aluminum hydroxide dry gel powder; further preferably, the pore-expanding agent is added in an amount of 3% to 15% by mass of the aluminum hydroxide dry gel powder, 5%, 6%, 8%, 10%, 12%, etc.

[0023] In the process (1) or the process (2), a peptizing agent is further added when the kneading solution is prepared, the peptizing agent being selected from at least one of inorganic acid, organic acid, and strongly acidic anion aluminum salt. For example, nitric acid, hydrochloric acid, oxalic acid, formic acid, acetic acid, citric acid, aluminum nitrate, etc., or a combination of several peptizing agents. The addition of the peptizing agent is beneficial to the kneading and shaping of the carrier.

[0024] In the process (1) or the process (2), the drying process is carried out at 100-130°C for 2-12 hours, and then the carrier is calcined at 400-500°C for 2-8 hours.

[0025] In the process (1) or the process (2), the calcination process is carried out at 400-500°C for 2-8 hours.

[0026] In the process (1) or the process (2), the shaping process is carried out by extruding the kneaded material into a strip shape on an extruder. The shape of the carrier can be adjusted by replacing the extruder hole plate, and the shape can be cylindrical or special-shaped (such as clover, four-leaf clover, five-toothed ball).

[0027] Preferably, in step S2, the impregnation process is carried out by placing the alumina carrier in the impregnation solution and rotating at 35-45°C for 20-60 min.

[0028] Preferably, in step S2, the impregnation is carried out 1-5 times; further preferably, in step S2, the impregnation is carried out 2-3 times. When the impregnation is carried out more than 1 time, the process is carried out by impregnating the alumina carrier once and calcining once, using the calcined catalyst carrier as the carrier again, impregnating the impregnation solution again and calcining until the number of impregnation reaches the desired number.

[0029] Preferably, in step S2, the calcination process is carried out at 400-500°C for 3-8 hours.

[0030] Preferably, the inert gas is selected from one of nitrogen, helium, neon, argon, or krypton. When a mixed gas atmosphere of inert gas and hydrogen is used, the volume percentage of the inert gas is 5% to 95%.

[0031] Preferably, after the roasting process in step S2, the process further comprises a reduction treatment and a passivation treatment. The reduction treatment is performed at 300-550 DEG C for 40-70 hours in a pure hydrogen atmosphere or a mixed atmosphere of inert gas and hydrogen. The passivation treatment is performed by surface passivation using an oxidizing gas, including one or more of oxygen, water vapor, carbon dioxide, and air, for 6-18 hours.

[0032] The application also provides a preparation method of polyether amine.

[0033] Specifically, the application provides a preparation method of polyether amine, which uses the supported nickel-based catalyst prepared by the above preparation method to synthesize polyether amine.

[0034] In the traditional impregnation method for preparing the catalyst, a metal salt solution is used to impregnate the carrier after roasting, and the carrier is subjected to collapse of the pore channel, reduction of the specific surface area, and reduction of the pore volume after roasting. In addition, the active component on the surface and in the pore channel of the carrier after impregnation is decomposed into an oxide through drying and roasting, and part of the pore channel of the carrier is blocked by the active component, resulting in loss of the inner surface area and uneven dispersion of the active component.

[0035] The application first uses the kneading method to add the active metal salt into the raw material to prepare the carrier through one-time molding, drying, and roasting, and the decomposition and dispersion of the active metal salt are simultaneously performed with the decomposition of the raw material in the roasting process of the carrier, and the active metal is retained in the pore channel of the carrier, thereby supporting the structure of the catalyst. The molding is improved by the carbon black pore expander, a part of the metal component is loaded by kneading, and another part of the metal component is loaded by coupling the impregnation method, thereby ensuring the pore structure of the catalyst and improving the metal loading amount.

[0036] Compared with the prior art, the application has the following beneficial effects:

[0037] (1) The supported nickel-based catalyst provided by the application improves the metal loading amount of the catalyst by adding a certain amount of active metal component in the molding process of the alumina carrier in the form of kneading, and maintains the pore structure of the catalyst in a relatively stable stage by modifying the pore expander, so that the carrier containing the active metal component can significantly improve the activity of the catalyst after impregnation by the metal solution.

[0038] (2) The application uses a new kneading method to prepare the carrier containing the active metal, and then uses the impregnation method to improve the active metal loading amount. The catalyst prepared by the method has the characteristics of large pore volume, large specific surface area, and uniform distribution of the active component, and the use of the catalyst to prepare polyether amine can significantly improve the conversion rate of polyol ether and the selectivity of primary amine, and reduce the generation of by-products.

[0039] (3) Compared with the co-precipitation method, the preparation method provided by the application has low production cost, simple process and is easier to realize industrialization. DETAILED DESCRIPTION

[0040] In order to make the skilled in the art more clearly understand the technical solutions described in the application, the following examples are listed for illustration. It should be pointed out that the following examples do not constitute a limitation on the scope of protection required by the application.

[0041] The raw materials, reagents or devices used in the following examples and comparative examples are commercially available or can be obtained by known methods unless otherwise specified.

[0042] Example 1

[0043] A preparation method of a supported nickel-based catalyst, comprising the following steps:

[0044] (1) Preparation of kneading solution: weigh 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, 0.1 g of chloroplatinic acid (39% Pt), 5 g of nitric acid and dissolve them in 90 g of deionized water, stir and mix to prepare a kneading solution.

[0045] (2) Kneading and shaping: weigh 80 g of aluminum hydroxide dry gel powder, mix evenly after adding 5 g of hydroxymethyl cellulose and 5 g of carbon black, first add the aqueous solution of silica sol (7.7 mL of silica sol dissolved in 15 mL of water, wherein the silica sol is 30% alkaline silica sol, and the particle size of silicon dioxide is 10-30 nm) to the mixture, knead evenly to make it into a fine powder, and obtain a kneaded fine powder. Then add the kneading solution to the kneaded fine powder, knead again until a uniform paste-like plastic material is obtained, extrude into 3 mm strips on an extruder, dry in a drying oven at 110°C for 3 hours, and then calcine in a high-temperature furnace at 550°C for 4 hours to prepare an alumina carrier containing active metal components.

[0046] (3) Preparation of impregnation solution: weigh 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, and 0.1 g of chloroplatinic acid (39% Pt), and dissolve them in 30 g of deionized water.

[0047] (4) Equal volume impregnation: immerse 82 g of the alumina carrier containing active metal components prepared in step (2) into the impregnation solution prepared in step (3), rotate and immerse in a rotary evaporator with a 40°C water bath for 30 min, heat to 90°C after adsorption equilibrium, vacuum dehydration and drying, and then calcine at 400°C for 4 h; then the calcined catalyst carrier is used as the carrier again, the impregnation solution is prepared in the same proportion, and the second impregnation, adsorption and calcination are carried out; finally, the calcined catalyst in the oxidation state is reduced in a reduction furnace at a hydrogen space velocity of 400 h -1The reduction was carried out at 420°C for 60 hours. After the reduction, water vapor was introduced to passivate the catalyst surface for 10 hours to obtain a supported nickel-based catalyst.

[0048] Example 2

[0049] A method for preparing a supported nickel-based catalyst includes the following steps:

[0050] (1) Preparation of kneading solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, 0.1 g of chloroplatinic acid (39% Pt), and 5 g of nitric acid were dissolved in 90 g of deionized water, and 7.7 mL of silica sol (30% alkaline silica sol, silica particle size 10-30 nm) was added dropwise while stirring.

[0051] (2) Kneading and molding: 80 g of aluminum hydroxide dry gel powder was weighed, 5 g of hydroxymethyl cellulose and 5 g of carbon black were added, and then the above prepared solution was added to the aluminum hydroxide dry gel powder containing hydroxymethyl cellulose and carbon black. After kneading into a uniform paste, it was extruded into a 3 mm strip on an extruder, dried in a drying oven at 110°C for 3 hours, and then calcined at 550°C for 4 hours in a high-temperature furnace to obtain an alumina carrier containing active metal components.

[0052] (3) Preparation of impregnation solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, and 0.1 g of chloroplatinic acid (39% Pt) were dissolved in 30 g of deionized water.

[0053] (4) Equal volume impregnation: 82 g of the alumina carrier containing active metal components prepared in step (2) was immersed in the impregnation solution prepared in step (3) and rotated and immersed in a rotary evaporator with a 40°C water bath for 30 minutes. After adsorption equilibrium, the temperature was increased to 90°C, vacuum dehydration and drying were performed, and then calcination was performed at 400°C for 4 hours. Then, the calcined catalyst carrier was used as a carrier again, the impregnation solution was prepared in the same proportion, and the second impregnation, adsorption, and calcination were performed. Finally, the calcined catalyst in the oxidized state was reduced in a reduction furnace at a hydrogen space velocity of 400 h-1 at 420°C for 60 hours. After the reduction was completed, water vapor was introduced to passivate the catalyst surface for 10 hours to obtain a supported nickel-based catalyst.

[0054] Example 3

[0055] A method for preparing a supported nickel-based catalyst includes the following steps:

[0056] (1) Preparation of kneading solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, 0.1 g of chloroplatinic acid (39% Pt), and 5 g of nitric acid were dissolved in 90 g of deionized water, and 7.7 mL of silica sol (30% alkaline silica sol, silica particle size 10-30 nm) was added dropwise while stirring.

[0057] (2) kneading: 80 g of aluminum hydroxide dry gel powder was weighed, 5 g of hydroxymethyl cellulose and 5 g of carbon black were added and mixed uniformly, an aqueous solution of silica sol (7.7 mL of silica sol dissolved in 15 mL of water, wherein the silica sol was 30% basic silica sol, and the particle size of the silica was 10-30 nm) was added first, and kneading was performed uniformly to make it into a fine powder, thereby obtaining a kneaded fine powder. The kneaded solution was added to the kneaded fine powder, and kneading was performed again until a uniform paste-like plastic material was obtained. The paste-like plastic material was extruded into a 3 mm strip on an extruder, dried in a drying oven at 110°C for 3 hours, and then calcined in a high-temperature furnace at 550°C for 4 hours, thereby obtaining an alumina carrier containing an active metal component.

[0058] (3) Preparation of impregnation solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, and 0.1 g of chloroplatinic acid (39% Pt) were dissolved in 30 g of deionized water.

[0059] (4) equal volume impregnation: 82 g of the alumina carrier containing an active metal component prepared in step (2) was immersed in the impregnation solution prepared in step (3), and rotary impregnation was performed in a rotary evaporator with a 40°C water bath for 30 min. After adsorption equilibrium, the temperature was increased to 90°C, vacuum dehydration and drying were performed, and then calcination was performed at 400°C for 4 h. Subsequently, the calcined catalyst carrier was used as a carrier again, the impregnation solution was prepared in the same proportion, and the second impregnation, adsorption, and calcination were performed. Finally, the oxidized catalyst after calcination was reduced in a reduction furnace at a hydrogen space velocity of 400 h -1 at 420°C for 60 h. After reduction, water vapor was introduced to passivate the surface of the catalyst for 10 h, thereby obtaining a supported nickel-based catalyst.

[0060] Example 4

[0061] A method for preparing a supported nickel-based catalyst, comprising the following steps:

[0062] (1) Preparation of kneading solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, and 0.1 g of chloroplatinic acid (39% Pt) were dissolved in 90 g of deionized water, and stirring and mixing were performed, thereby obtaining a kneading solution.

[0063] (2) Kneading: 80 g of aluminum hydroxide dry gel powder was weighed, 5 g of hydroxymethyl cellulose and 5 g of carbon black were added and mixed uniformly, and then a silicon sol aqueous solution (7.7 mL of silicon sol dissolved in 15 mL of water, wherein the silicon sol was 30% basic silicon sol, and the particle size of silicon dioxide was 10-30 nm) was added and kneaded uniformly to make it into a fine powder, thereby obtaining a kneaded fine powder. The kneaded solution was added to the kneaded fine powder, and kneading was performed again until a uniform paste was obtained. The paste was extruded into a 3 mm strip on an extruder, dried in a drying oven at 110°C for 3 hours, and then calcined in a high-temperature furnace at 550°C for 4 hours, thereby obtaining an aluminum oxide carrier containing an active metal component.

[0064] (3) Preparation of impregnation solution: 30 g of nickel nitrate hexahydrate, 3.25 g of cobalt nitrate hexahydrate, 1.95 g of copper nitrate pentahydrate, and 0.05 g of chloroplatinic acid (39% Pt) were dissolved in 15 g of deionized water.

[0065] (4) Equal volume impregnation: 82 g of the aluminum oxide carrier containing an active metal component prepared in step (2) was immersed in the impregnation solution prepared in step (3) and rotated and immersed in a rotary evaporator with a 40°C water bath for 30 min. After adsorption equilibrium, the temperature was increased to 90°C, vacuum dehydration and drying were performed, and then calcination was performed at 400°C for 4 h. Subsequently, the calcined catalyst carrier was used as a carrier again, the impregnation solution was prepared in the same proportion, and the second impregnation, adsorption, and calcination were performed. Finally, the oxidized catalyst after calcination was reduced in a reduction furnace at a hydrogen space velocity of 400 h -1 for 60 h at 420°C. After reduction, water vapor was introduced to passivate the surface of the catalyst for 10 h, thereby obtaining a nickel-based supported catalyst.

[0066] Comparative Example 1

[0067] A method for preparing an aluminum oxide carrier containing an active metal component, comprising the following steps:

[0068] (1) Preparation of kneading solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, 0.1 g of chloroplatinic acid (39% Pt), and 5 g of nitric acid were dissolved in 90 g of deionized water.

[0069] (2) Kneading: 80 g of aluminum hydroxide dry gel powder was weighed, 5 g of hydroxymethyl cellulose was added, and the kneading solution was added to the aluminum hydroxide dry gel powder containing hydroxymethyl cellulose. Kneading was performed until a uniform paste was obtained. The paste was extruded into a 3 mm strip on an extruder, dried in a drying oven at 110°C for 3 hours, and then calcined in a high-temperature furnace at 550°C for 4 hours, thereby obtaining an aluminum oxide carrier containing an active metal component.

[0070] Comparative Example 2

[0071] A method for preparing an alumina support containing an active metal component, comprising the steps of:

[0072] (1) Preparing a kneading solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, 0.1 g of chloroplatinic acid (39% Pt), and 5 g of nitric acid were dissolved in 90 g of deionized water, and mixed by stirring to prepare a kneading solution.

[0073] (2) Kneading and molding: 80 g of aluminum hydroxide dry gel powder was mixed with 5 g of hydroxymethyl cellulose and 5 g of carbon black, and then 7.7 mL of a silica sol (30% basic silica sol, silica particle size 10-30 nm) was added dropwise to the mixture, and kneaded to make a fine powder. The kneading solution was added to the fine powder, and kneaded again until a uniform paste was obtained. The paste was extruded into a 3 mm strip on an extruder, and dried in a drying oven at 110°C for 3 hours. The dried product was calcined in a high-temperature furnace at 550°C for 4 hours to prepare an alumina support containing an active metal component.

[0074] Comparative Example 3

[0075] A method for preparing an alumina support containing an active metal component, comprising the steps of:

[0076] (1) Preparing a kneading solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, 0.1 g of chloroplatinic acid (39% Pt), and 5 g of nitric acid were dissolved in 90 g of deionized water, and mixed by stirring to prepare a kneading solution.

[0077] (2) Kneading and molding: 80 g of aluminum hydroxide dry gel powder was mixed with 5 g of hydroxymethyl cellulose and 5 g of carbon black, and then 7.7 mL of a silica sol (30% basic silica sol, silica particle size 10-30 nm) was added dropwise to the mixture, and kneaded to make a fine powder. The kneading solution was added to the fine powder, and kneaded again until a uniform paste was obtained. The paste was extruded into a 3 mm strip on an extruder, and dried in a drying oven at 110°C for 3 hours. The dried product was calcined in a high-temperature furnace at 550°C for 4 hours to prepare an alumina support containing an active metal component.

[0078] Comparative Example 4

[0079] A method for preparing a nickel-based supported catalyst, comprising the steps of:

[0080] (1) Preparation of pure alumina carrier: 200 g of aluminum hydroxide dry gel powder was weighed, 10 g of hydroxymethyl cellulose was added, 4 g of nitric acid was diluted in 160 mL of deionized water, and then added to the aluminum hydroxide dry gel powder containing hydroxymethyl cellulose, and then kneaded into a uniform paste, and then extruded into 3 mm strips on an extruder, and then dried in a drying oven at 110°C for 3 hours, and then calcined in a high-temperature furnace at 550°C for 4 hours to obtain a pure alumina carrier.

[0081] (2) Preparation of impregnation solution: 60 g of nickel nitrate hexahydrate, 6.5 g of cobalt nitrate hexahydrate, 3.9 g of copper nitrate pentahydrate, and 0.1 g of chloroplatinic acid (39% Pt) were dissolved in 42 g of deionized water.

[0082] (3) Equal volume impregnation: 65 g of the pure alumina carrier prepared in step (1) was immersed in the impregnation solution prepared in step (2), and rotated and immersed in a 40°C water bath for 30 min, and then heated to 90°C to remove water by vacuum drying, and then calcined at 400°C for 4 h; then the calcined catalyst carrier was used as a carrier again, and the impregnation solution was prepared in the same proportion, and the second impregnation, adsorption and calcination were carried out; finally, the oxidized catalyst was reduced in a reduction furnace at a hydrogen space velocity of 400 h -1 for 60 hours at 420°C. After reduction, water vapor was introduced for 10 h to passivate the surface of the catalyst, and a nickel-based supported catalyst was obtained.

[0083] Product effect test

[0084] (1) Physical adsorption characterization test was carried out on the nickel-based supported catalyst or alumina carrier containing active metal components prepared in Examples 1-4 and Comparative Examples 1-4, including specific surface area, pore size, and pore volume. The specific characterization data is shown in Table 1.

[0085] Table 1 Physical adsorption characterization data

[0086] Group Specific surface (m 2 / g) Pore size (nm) Pore volume (cm 3 / g) Comparative Example 4 98 6 0.34 Comparative Example 3 225 16 0.56 Comparative Example 1 216 10 0.46 Comparative Example 2 233 21 0.61 Example 1 205 17 0.36 Example 2 197 14 0.30 Example 3 209 15 0.50 Example 4 221 17 0.57

[0087] From the data in Table 1, it can be seen from Comparative Example 1 and Comparative Example 4 that the specific surface area of the alumina carrier catalyst containing active metal components prepared by the kneading method of Comparative Example 1 is higher than that of the catalyst prepared by the impregnation method of Comparative Example 4. This is because the catalyst prepared by the kneading method is prepared by adding a metal salt solution to the raw material, once forming, drying and calcining, and in the calcination process of the catalyst, the decomposition and dispersion of the active component metal salt are carried out simultaneously with the decomposition of the raw material, the active component is retained in the pores of the carrier, and the structure of the catalyst is supported, so the kneading method catalyst has a large specific surface area. The catalyst prepared by the impregnation method is prepared by impregnating the carrier after calcination with a metal salt solution, and after the carrier is calcined twice, the pore collapses, the specific surface area and pore volume decrease. In addition, the active components on the surface and in the pores of the carrier are decomposed into oxides after drying and calcination, part of the pores of the carrier are blocked by the active components, resulting in the loss of internal surface area and uneven dispersion of the active components.

[0088] From Comparative Example 1 and Comparative Example 2, it can be seen that the alumina carrier containing active metal components prepared by kneading with carbon black as a pore-expanding agent in Comparative Example 2 improves the pore structure of the catalyst compared to Comparative Example 1 without the pore-expanding agent. The pore-expanding principle of physical pore-expanding agents such as carbon black is that during calcination, the pore-expanding agent wrapped in the aluminum hydroxide dry gel powder is oxidized into gas and escapes, releasing the space originally occupied, resulting in an increase in the specific surface area, pore volume and pore size of the carrier. The pore-expanding effect of the pore-expanding agent molecules is related to the kinetic diameter of the pore-expanding agent molecules. After adding carbon black, the pore size in the carrier range increases, which is basically consistent with the particle size of the carbon black particles used, and Comparative Example 2 verifies this point.

[0089] From Comparative Example 2 and Comparative Example 3, it can be seen that the pore structure of the alumina carrier containing active metal components prepared by adding silica sol to the aluminum hydroxide dry gel powder mixed with the extrusion aid and carbon black in Comparative Example 2 is more excellent than that of the alumina carrier containing active metal components prepared by adding silica sol to the metal mixed solution in Comparative Example 3. This is because the alkaline silica sol may have undergone a neutralization reaction with the metal salt solution, resulting in uneven distribution of the silica sol and metal salt in the catalyst.

[0090] Examples 1 and 2 further impregnate the alumina carriers containing active metal components prepared in Comparative Examples 2 and 3 with a metal solution and calcine and reduce to prepare nickel-based supported catalysts. After further impregnation and calcination and reduction, the specific surface area, pore size and pore volume of the material slightly decrease.

[0091] (2) Analyze the metal elements of the nickel-based supported catalysts or alumina carriers containing active metal components prepared in Examples 1-4 and Comparative Examples 1-4. The metal element analysis data are shown in Table 2.

[0092] Table 2 Metal element analysis data

[0093] Group Ni (%) Co (%) Cu (%) Pt (%) Comparative Example 4 28.8 3.00 2.60 0.041 Comparative Example 3 15.12 1.43 1.26 0.025 Comparative Example 1 14.74 1.56 1.29 0.028 Comparative Example 2 15.01 1.49 1.32 0.024 Example 1 40.16 4.23 3.91 0.062 Example 2 39.61 4.09 4.03 0.068 Example 3 26.09 2.96 2.73 0.038 Example 4 24.15 3.45 4.18 0.043

[0094] From the data of Table 2, it can be seen from Comparative Example 4 and Example 1 that the loading of active metal can be greatly improved by coupling the loading with the shaping process to prepare shaped catalysts. The catalyst of Comparative Example 4 was prepared by impregnation, and after two drying and calcination processes, the pore structure of the catalyst collapsed, resulting in a decrease in the specific surface area and pore volume. Since the isovolume impregnation is based on impregnating the active component in the form of a salt solution onto the porous support and penetrating into the inner surface, due to the limitation of water absorption, the loading of the active component cannot be further improved by multiple impregnation. As can be seen from Comparative Examples 2 and 3 and Examples 1 and 2, by kneading the catalyst with the carbon black pore expander to load part of the metal component, and at the same time coupling the impregnation method to load another part of the metal component, the metal loading is improved while the pore structure of the catalyst is ensured.

[0095] (3) Catalyst performance evaluation

[0096] The nickel-based supported catalysts or alumina carriers containing active metal components prepared in Examples 1-4 and Comparative Examples 1-4 were evaluated for catalytic performance. Polyoxypropylene-based diamines (D-230) were synthesized using each group of nickel-based supported catalysts or alumina carriers containing active metal components, according to the following process: A fixed bed reactor was loaded with 30 mL of catalyst or alumina carrier in a bulk volume, and was reduced at 250°C using a mixture of 10% hydrogen and 90% nitrogen for 12 hours. After reduction, the temperature was lowered to 200°C, the system pressure was raised to 15 MPa, and the feed was started. The PPG-230 (polypropylene glycol ether) space velocity was 0.5 h-1, the liquid ammonia / PPG-230 molar ratio was 8:1, and the hydrogen / PPG-230 molar ratio was 0.8:1. Excess ammonia and water were removed by distillation, and the reaction products were analyzed by gas chromatography. Samples were taken for analysis after 60 hours. -1

[0097] The total amine value was determined by titration of the product with 0.5 mol / L hydrochloric acid solution, and the total amine value of the product was calculated from the amount of hydrochloric acid consumed.

[0098] The secondary / tertiary amine value was determined by mixing the product with an equal amount of salicylaldehyde and stirring for 2 hours, then titrating the product with 0.5 mol / L hydrochloric acid solution, and calculating the sum of the secondary and tertiary amine values of the product from the amount of hydrochloric acid consumed.

[0099] The primary amine selectivity = (total amine value - secondary / tertiary amine value) / total amine value x 100%.

[0100] The alcohol conversion rate = total amine value of product / total hydroxyl value of raw material x 100%.

[0101] The results of the activity evaluation of each group of catalysts are shown in Table 3.​

[0102] The results of the evaluation of the activity of the catalysts of each group in Table 3

[0103]

[0104] From the data in Table 3, it can be seen that the overall activity of the catalysts prepared in Examples 1-4 of the present application is significantly better than that of the catalyst of Comparative Example 4. The nickel-based supported catalyst prepared in the present application significantly improves the conversion rate of PPG-230 and the primary amine selectivity, meaning that the level of hydrogenolysis by-products is low. The nickel-based supported catalyst prepared in the present application is an ideal catalyst for the synthesis of polyether amines.

[0105] The above-described examples only express several embodiments of the present application, and the description is relatively specific and detailed, but it should not be understood as limiting the scope of the patent of the present application. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A process for the preparation of a supported nickel-based catalyst, characterized in that, The method comprises the following steps: S1, dissolving a first active metal source in water to prepare a kneading solution; taking aluminum hydroxide dry gel powder, adding a extrusion aid, a pore-expanding agent and a silica sol, mixing uniformly, then adding the kneading solution for kneading, and then forming, drying and calcining to prepare an alumina carrier containing an active metal component; S2, preparing an impregnation solution by using a second active metal source, then impregnating the alumina carrier prepared in step S1, and then calcining to prepare a supported nickel-based catalyst; In step S1 and step S2, the first active metal source and the second active metal source both comprise a nickel source, a platinum source, a copper source and a cobalt source; the first active metal source and the second active metal source are the same; In the first active metal source, the molar ratio of nickel, platinum, copper and cobalt in the nickel source, the platinum source, the copper source and the cobalt source is 1:(0.0008-0.002):(0.06-0.08):(0.05-0.2); The pore-expanding agent is carbon black.

2. The production method according to claim 1, characterized by, The silica sol comprises an alkaline silica sol or an acidic silica sol.

3. The production method according to claim 1 or 2, characterized by, The extrusion aid comprises at least one of amaranth powder, starch, cellulose and carbon powder.

4. The method of claim 1, wherein, In step S1, when the kneading solution is prepared, a peptizing agent is also added; the peptizing agent is selected from at least one of inorganic acid, organic acid and strong acidic anion aluminum salt.

5. The preparation method according to claim 1, characterized in that, In step S1, the calcination process is calcination at 400-500°C for 2-8 hours.

6. The method of claim 1, wherein, In step S2, the impregnation process is that the alumina carrier is placed in the impregnation solution, impregnated at 35-45°C in a rotating state for 20-60 min.

7. The preparation method according to claim 1, characterized in that, In step S2, the calcination process is calcination at 400-500°C for 3-8 hours.

8. A process for the preparation of a polyetheramine, characterized in that, The supported nickel-based catalyst prepared by the preparation method in any one of claims 1-7 is used for synthesizing polyether amine.

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