Cyclohexanol dehydrogenation cyclohexanone catalyst and preparation method thereof

Abstract

The invention discloses a catalyst for preparing cyclohexanone through cyclohexanol dehydrogenation. The catalyst comprises an active component, a carrier and an auxiliary agent, the content of the active component is 1%-50%, the content of the carrier is 50%-98%, and the content of the auxiliary agent is 0.2%-1% based on the mass percentage of the catalyst; the active component comprises copper oxide, and the carrier is purified Na-montmorillonite modified by a silane coupling agent. The purified Na-montmorillonite modified by the silane coupling agent is used as the catalyst for preparing cyclohexanone by dehydrogenation of copper-based cyclohexanol, so that the specific surface area and thermal stability of the catalyst can be effectively improved, meanwhile, the activity of the catalyst with low active component content is improved, and the utilization rate of the active component is improved. When the loading amount of the active component of the catalyst is lower than 10%, the catalyst still has relatively high activity and cyclohexanone selectivity, and relatively high thermal stability.

Description

Technical Field

[0001] The invention belongs to the technical field of catalysts, and particularly relates to a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol and a preparation method thereof. Background Art

[0002] Cyclohexanone is an important organic chemical raw material and a key intermediate for the synthesis of caprolactam and adipic acid. It is currently mainly prepared by cyclohexanol oxidation and dehydrogenation in industry. Among them, dehydrogenation is widely used in the industrial production of cyclohexanone due to relatively few by-products, simple operation, high yield, and process safety. The catalytic performance of the catalyst in the process of preparing cyclohexanone by cyclohexanol dehydrogenation has a crucial impact on the conversion rate of cyclohexanol and the selectivity of cyclohexanone. The conventional catalyst type used in the prior art is a copper-based catalyst, and the preparation process of such catalysts is generally to load the active component on a carrier of an oxide or a composite oxide. For example, the patent number CN 109331826 A discloses a catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol, its preparation method and application, the catalyst comprises: ZnAl2O4 carrier, CuO active component and ZnO active component, La2O3 auxiliary agent, wherein the content of CuO is 10-15wt%, the content of ZnO is 20-25wt%, and the content of La2O3 auxiliary agent is 2-5wt% based on the mass of the catalyst. The patent number CN 111036230 A discloses a catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol and its preparation method, characterized in that the active components of the catalyst are Cu2O and ZnO, MgO is used as the main body of the carrier, and a carrier structure auxiliary agent is added; the mass percentage of the active component Cu2O of the catalyst is 30%-40%, the mass percentage of ZnO is 10%-15%; the mass percentage of MgO in the carrier is 40%-50%; the mass percentage of the carrier structure auxiliary agent is 5%-10%. However, when using oxides or composite oxides as carriers to prepare catalysts for cyclohexanol dehydrogenation to cyclohexanone, there are generally problems such as high active metal component content, low active component utilization, low active specific surface area, and general high temperature stability, which cannot meet people's needs. Summary of the invention

[0003] The invention aims to solve the technical problems in the prior art that the catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol has high content of active metal components, low utilization rate of active components, low active specific surface area and general high-temperature stability. The invention provides a catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol and a preparation method thereof, so as to effectively improve the specific surface area and thermal stability of the catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol, improve the activity of the catalyst with low content of active components and improve the utilization rate of active components.

[0004] In order to achieve the above object, the present invention adopts the following technical scheme:

[0005] A catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol, comprising an active component, a carrier and an auxiliary agent;

[0006] In terms of mass percentage of the catalyst, the active ingredient content is 1% to 50%, the carrier content is 50% to 98%, and the additive content is 0.2% to 1%;

[0007] The active ingredient includes copper oxide, and the carrier is purified sodium-based montmorillonite modified by a silane coupling agent.

[0008] Furthermore, the silane coupling agent is one of n-alkyltrimethoxysilane, γ-aminopropyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane, wherein n=12, 14, or 16.

[0009] Furthermore, in terms of mass percentage of the catalyst, the active ingredient content is 5% to 30%, the carrier content is 70% to 94%, and the auxiliary agent content is 0.2% to 1%.

[0010] Furthermore, the auxiliary agent is one of sodium oxide, potassium oxide, calcium oxide or magnesium oxide.

[0011] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0012] (1) Preparation of organic soil

[0013] Weigh sodium montmorillonite and silane coupling agent according to the weight ratio and add them into deionized water and stir evenly, adjust the pH to 6.0-6.8, heat to 70-80°C, react at a constant temperature for 2h-3h, cool to room temperature, filter, wash, dry and grind to obtain organic soil;

[0014] Wherein, the sodium-montmorillonite is 50 parts by weight, and the silane coupling agent is 5 to 20 parts by weight.

[0015] (2) Preparation of organic soil-supported copper catalyst

[0016] The organic soil obtained in step (1) is weighed by weight, added to a mixture of deionized water and methanol with a methanol volume fraction of 0% to 10%, stirred and heated to 45°C to 55°C, stirred at a constant temperature for 8min to 15min, and then an alkaline solution and an auxiliary agent are added respectively. After continuing to stir at a constant temperature for 8min to 15min, a copper salt solution is added and the pH value of the mixed solution is adjusted to 6.2 to 6.8. After continuing to stir at a constant temperature for 1h, the mixture is cooled to room temperature, filtered, washed, dried, ground and calcined in an air atmosphere at 300°C to 600°C for 3h to obtain an organic soil-supported copper catalyst;

[0017] Wherein, the organic soil is 1 part by weight, and the deionized water and methanol mixed solution is 20 to 50 parts by weight;

[0018] The organic soil-loaded copper catalyst comprises active ingredients, and the active ingredients comprise copper oxide. The active ingredients account for 1% to 50% of the mass percentage of the organic soil-loaded copper catalyst in terms of copper oxide.

[0019] Furthermore, the silane coupling agent is one of n-alkyltrimethoxysilane, γ-aminopropyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane, wherein n=12, 14, or 16.

[0020] Furthermore, the alkaline solution is one of sodium carbonate or sodium hydroxide.

[0021] Furthermore, the copper salt solution is one of a copper nitrate solution, a copper sulfate solution or a copper chloride solution with a concentration of 0.1 to 1 mol / L.

[0022] Furthermore, the amount of the copper salt solution added is calculated based on the mass percentage of the active ingredient in terms of copper oxide to the copper catalyst supported by the organic soil, and the calculation formula is as follows:

[0023]

[0024] in, is the amount of copper in the copper salt solution, m1 is the mass of the organic soil carrier, wt% is the mass percentage of copper oxide, M (CuO) is the molar mass of copper oxide.

[0025] Furthermore, the molar ratio of the alkaline solution to the copper salt solution is (1.5-2):1.

[0026] The beneficial effects of the present invention are:

[0027] The present invention adopts purified sodium-based montmorillonite modified by a silane coupling agent as a copper-based cyclohexanol dehydrogenation catalyst to prepare cyclohexanone, which can effectively improve the specific surface area and thermal stability of the catalyst, while improving the activity of the catalyst with a low active component content, and improving the utilization rate of the active component. Among them, due to the special layered structure of montmorillonite, the use of montmorillonite as a carrier of the catalyst can provide a higher specific surface area for catalysis, and due to the presence of silicon-oxygen bonds on the organic montmorillonite modified by the silane coupling agent, a stable Si-O-Cu bond is formed in the process of loading the copper-based catalyst, which plays a fixing role on copper, thereby improving the catalytic stability of the catalyst. At the same time, the Si-O-Cu bond will limit the change of the copper valence state before the catalytic reaction occurs, making the copper species more single, thereby improving the selectivity of the catalyst during the catalytic reaction. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be described more clearly and completely below. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meaning understood by people with general skills in the field to which the present invention belongs.

[0029] The words "first", "second" and similar words used in the patent application specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "one", "an" or "the" and similar words do not indicate a quantitative limitation, but indicate the existence of at least one. Words such as "include" or "comprise" mean that the elements or objects appearing before "include" or "comprise" cover the features, wholes, steps, operations, elements and / or components listed after "include" or "comprise", and do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0030] Example 1

[0031] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0032] (1) Preparation of organic soil

[0033] Weigh 50g of sodium montmorillonite and 10g of hexadecyltrimethoxysilane, add the weighed sodium montmorillonite and hexadecyltrimethoxysilane into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0034] (2) Preparation of organic soil-supported copper catalyst

[0035] Weigh 45g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 10% in terms of copper oxide, recorded as 1#.

[0036] Example 2

[0037] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0038] (1) Preparation of organic soil

[0039] Weigh 50g of sodium montmorillonite and 10g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH550 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0040] (2) Preparation of organic soil-supported copper catalyst

[0041] Weigh 45g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200 mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 10% in terms of copper oxide, recorded as 2#.

[0042] Example 3

[0043] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0044] (1) Preparation of organic soil

[0045] Weigh 50g of sodium montmorillonite and 10g of silane coupling agent KH570, add the weighed sodium montmorillonite and silane coupling agent KH570 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0046] (2) Preparation of organic soil-supported copper catalyst

[0047] Weigh 45g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in a 90°C oven for 8h, grind it into powder, pass it through a 200 mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 10% in terms of copper oxide, recorded as 3#.

[0048] Example 4

[0049] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0050] (1) Preparation of organic soil

[0051] Weigh 100g of sodium montmorillonite and 20g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH570 into 2000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0052] (2) Preparation of organic soil-supported copper catalyst

[0053] Weigh 95g of the organic soil obtained in step (1), add it to a mixture of 1950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in a 90°C oven for 8h, grind it into powder, pass it through a 200 mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the organic soil-supported copper catalyst has an active ingredient mass percentage of 5% in terms of copper oxide, recorded as 4#.

[0054] Example 5

[0055] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0056] (1) Preparation of organic soil

[0057] Weigh 50g of sodium montmorillonite and 10g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH570 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0058] (2) Preparation of organic soil-supported copper catalyst

[0059] Weigh 40g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 250mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 250mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200 mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 20% in terms of copper oxide, recorded as 5#.

[0060] Example 6

[0061] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0062] (1) Preparation of organic soil

[0063] Weigh 50g of sodium montmorillonite and 10g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH550 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0064] (2) Preparation of organic soil-supported copper catalyst

[0065] Weigh 35g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 375mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 375mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200 mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the organic soil-supported copper catalyst has an active ingredient mass percentage of 30% in terms of copper oxide, recorded as 6#.

[0066] Example 7

[0067] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0068] (1) Preparation of organic soil

[0069] Weigh 50g of sodium montmorillonite and 10g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH550 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0070] (2) Preparation of organic soil-supported copper catalyst

[0071] Weigh 30g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 500mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 500mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 40% in terms of copper oxide, recorded as 7#.

[0072] Example 8

[0073] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0074] (1) Preparation of organic soil

[0075] Weigh 50g of sodium montmorillonite and 15g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH550 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0076] (2) Preparation of organic soil-supported copper catalyst

[0077] Weigh 45g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of a 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the organic soil-supported copper catalyst has an active ingredient mass percentage of 10% in terms of copper oxide, recorded as 8#.

[0078] Example 9

[0079] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0080] (1) Preparation of organic soil

[0081] Weigh 50g of sodium montmorillonite and 10g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH550 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0082] (2) Preparation of organic soil-supported copper catalyst

[0083] Weigh 45g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of a 0.7mol / L sodium carbonate solution and 0.5g of sodium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200 mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 10% in terms of copper oxide, recorded as 9#.

[0084] Example 10

[0085] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0086] (1) Preparation of organic soil

[0087] Weigh 50g of sodium montmorillonite and 10g of silane coupling agent KH550, add the weighed sodium montmorillonite and silane coupling agent KH550 into 1000mL of deionized water in turn and stir evenly, adjust the pH to 6.5 with 0.1mol / L nitric acid or sodium carbonate, heat to 75°C in a water bath, react at a constant temperature for 2.5h, then cool to room temperature, filter and wash with deionized water 3 times, then place in a 90°C oven to dry for 8h, grind and sieve through a 200-mesh sieve to obtain organic soil.

[0088] (2) Preparation of organic soil-supported copper catalyst

[0089] Weigh 45g of the organic soil obtained in step (1), add it to a mixed solution of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of a 0.7mol / L sodium hydroxide solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of a 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain an organic soil-supported copper catalyst. Wherein, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 10% in terms of copper oxide, recorded as 10#.

[0090] Comparative Example 1

[0091] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0092] Weigh 45g of magnesium oxide powder, add it to a mixture of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain a magnesium oxide-supported copper catalyst. Among them, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 10% in terms of copper oxide, recorded as 11#.

[0093] The difference between this comparative example 1 and the above-mentioned example 2 is that the catalyst carrier is different.

[0094] Comparative Example 2

[0095] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0096] Weigh 95g of magnesium oxide powder, add it to a mixture of 1950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 125mL of 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 125mL of 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain a magnesium oxide-supported copper catalyst. Among them, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 5% in terms of copper oxide, recorded as 12#.

[0097] The difference between this comparative example 2 and the above-mentioned example 4 is that the catalyst carrier is different.

[0098] Comparative Example 3

[0099] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0100] Weigh 40g of magnesium oxide powder, add it to a mixture of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 250mL of 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 250mL of 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain a magnesium oxide-supported copper catalyst. Among them, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 20% in terms of copper oxide, recorded as 13#.

[0101] The difference between this comparative example 3 and the above-mentioned example 5 is that the catalyst carrier is different.

[0102] Comparative Example 4

[0103] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0104] Weigh 35g of magnesium oxide powder, add it to a mixture of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 375mL of 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 375mL of 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain a magnesium oxide-supported copper catalyst. Among them, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 30% in terms of copper oxide, recorded as 14#.

[0105] The difference between this comparative example 4 and the above-mentioned example 6 is that the catalyst carrier is different.

[0106] Comparative Example 5

[0107] A method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol comprises the following steps:

[0108] Weigh 30g of magnesium oxide powder, add it to a mixture of 950mL of deionized water and 50mL of methanol, stir and heat it in a water bath to 50°C, continue to stir in a water bath at a constant temperature for 10min, then add 500mL of 0.7mol / L sodium carbonate solution and 0.5g of potassium oxide powder in sequence, continue to stir in a water bath at a constant temperature for 10min, add 500mL of 0.5mol / L copper nitrate solution dropwise with a separatory funnel, then quickly adjust the pH to 6.5 with a small amount of 0.1mol / L nitric acid solution, continue to stir at a constant temperature for 1h, and then cool to room temperature to obtain a reaction precipitate, wash it 3 times with deionized water, filter it by suction, dry it in an oven at 90°C for 8h, grind it into powder, pass it through a 200-mesh sieve, and calcine it in an air atmosphere at 500°C for 3h to obtain a magnesium oxide-supported copper catalyst. Among them, the mass percentage of active ingredients in the organic soil-supported copper catalyst is 40% in terms of copper oxide, recorded as 15#.

[0109] The difference between this comparative example 5 and the above-mentioned example 7 is that the catalyst carrier is different.

[0110] Catalyst performance characterization test

[0111] The specific surface area and pore structure of the catalysts obtained in each embodiment and comparative example were measured using an American Quantachrome NOVA-2200e automatic adsorption instrument. The adsorbate was N2, the adsorption temperature was 77K, the specific surface area was calculated using the BET equation, and the pore volume and pore size were calculated using the BJH method. The characterization results of each embodiment and comparative example are shown in Table 1 below:

[0112] Table 1 Performance characterization results of the catalysts obtained in each embodiment and comparative example

[0113] serial number <![CDATA[Specific surface area (m 2 / g)]]> Pore ​​volume (mL / g) Average pore diameter (nm) 1# 307 0.29 3.13 2# 383 0.40 4.38 3# 328 0.35 3.37 4# 376 0.39 4.21 5# 354 0.37 4.03 6# 323 0.30 3.38 7# 305 0.31 3.27 8# 399 0.56 5.85 9# 368 0.39 4.18 10# 338 0.29 3.17 11# 232 0.26 3.11 12# 230 0.25 3.05 13# 228 0.27 3.07 14# 229 0.26 3.09 15# 225 0.25 3.08

[0114] From the characterization results of Examples 1-10 and Comparative Examples 1-5 in the above table, it can be seen that compared with using magnesium oxide as a carrier of a copper-based catalyst, the catalyst prepared by the method of the present invention using organic clay modified with a silane coupling agent as a carrier of a copper-based catalyst can obtain a higher specific surface area and a larger pore structure, whether it is a catalyst with a high content of active ingredients or a catalyst with a low content of active ingredients.

[0115] Performance testing

[0116] The catalysts obtained in the above embodiments and comparative examples were used for the dehydrogenation of cyclohexanol to cyclohexanone to compare the activity of the catalysts obtained in the embodiments and comparative examples. The above reaction was carried out in a fixed bed reactor with a catalyst loading of 50 mL. The catalyst was first reduced with H2 at normal pressure and 260°C for 3 h, and then the raw material cyclohexanol liquid was heated at a space velocity of 0.6 h -1, the reaction temperature was 250°C and the reaction was carried out under normal pressure. The final results are shown in Table 2 below:

[0117] Table 2 Activity test results of the catalysts obtained in each embodiment and comparative example

[0118] catalyst Cyclohexanol conversion rate / % Cyclohexanone selectivity / % Catalyst stability (hours) 1# 61.58 99.52 ≥2000 2# 69.78 99.82 ≥2000 3# 63.77 99.79 ≥2000 4# 64.58 99.81 ≥2000 5# 66.23 99.78 ≥2000 6# 68.08 99.79 ≥2000 7# 67.46 99.70 ≥2000 8# 68.68 99.73 ≥2000 9# 65.75 99.43 ≥2000 10# 63.22 99.13 ≥2000 11# 42.65 89.01 ≥1000 12# 33.77 80.20 ≥1000 13# 46.98 93.09 ≥1000 14# 50.20 97.21 ≥1000 15# 59.35 99.15 ≥1000

[0119] It can be seen from the test results of Examples 1-10 in the above table that the catalysts prepared by the method of the present invention can have excellent cyclohexanol conversion and cyclohexanone selectivity, and the catalyst activity stability is high. Even when the active component content in the catalyst is only 5% (Example 4), the cyclohexanol conversion of the catalyst can still reach 63.98%, the cyclohexanone selectivity can reach 99.81%, and the stability of the catalyst is still ≥2000.

[0120] It can be seen from the test results of Comparative Examples 1-5 that when magnesium oxide is used as the carrier of the catalyst, the content of the active ingredient in the catalyst has a significant effect on the activity of the catalyst. As shown in the results of Comparative Example 2, when the content of the active ingredient in the catalyst is 5%, the cyclohexanol conversion rate of the catalyst when used is 33.77%, and the cyclohexanone selectivity is only 80.20%. When the content of the active ingredient in the catalyst reaches 40%, although the catalyst can obtain a relatively high cyclohexanol conversion rate and cyclohexanone selectivity when used, the stability of the catalyst is still insufficient compared to the present invention.

[0121] Finally, it should be noted that these embodiments are only used to illustrate the present invention and do not limit the scope of the present invention. In addition, for those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. The obvious changes or modifications derived from them are still within the scope of protection of the present invention.

Claims

1. A catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol, comprising an active ingredient, a carrier and an auxiliary agent; characterized in that: In terms of mass percentage of the catalyst, the active ingredient content is 1% to 50%, the carrier content is 50% to 98%, and the additive content is 0.2% to 1%; The active ingredient includes copper oxide, and the carrier is purified sodium-based montmorillonite modified by a silane coupling agent.

2. The catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol according to claim 1, characterized in that: The silane coupling agent is one of n-alkyl trimethoxysilane, γ-aminopropyl triethoxysilane and γ-methacryloxypropyl trimethoxysilane, wherein n=12, 14 or 16.

3. The catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol according to claim 1, characterized in that: Calculated by mass percentage of the catalyst, the content of the active ingredient is 5% to 30%, the content of the carrier is 70% to 94%, and the content of the auxiliary agent is 0.2% to 1%.

4. The catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol according to claim 1, characterized in that: The auxiliary agent is one of sodium oxide, potassium oxide, calcium oxide or magnesium oxide.

5. A method for preparing a catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol, characterized in that: The steps include: (1) Preparation of organic soil Weigh sodium montmorillonite and silane coupling agent according to the weight ratio and add them into deionized water and stir evenly, adjust the pH to 6.0-6.8, heat to 70-80°C, react at a constant temperature for 2h-3h, cool to room temperature, filter, wash, dry and grind to obtain organic soil; Wherein, the sodium montmorillonite is 50 parts by weight, and the silane coupling agent is 5 to 20 parts by weight; (2) Preparation of organic soil-supported copper catalyst The organic soil obtained in step (1) is weighed by weight, added to a mixture of deionized water and methanol with a methanol volume fraction of 0% to 10%, stirred and heated to 45°C to 55°C, stirred at a constant temperature for 8min to 15min, and then an alkaline solution and an auxiliary agent are added respectively. After continuing to stir at a constant temperature for 8min to 15min, a copper salt solution is added and the pH value of the mixed solution is adjusted to 6.2 to 6.

8. After continuing to stir at a constant temperature for 1h, the mixture is cooled to room temperature, filtered, washed, dried, ground and calcined in an air atmosphere at 300°C to 600°C for 3h to obtain an organic soil-supported copper catalyst; Wherein, the organic soil is 1 part by weight, and the mixed solution of deionized water and methanol is 20 to 50 parts by weight; The organic soil-loaded copper catalyst comprises active ingredients, and the active ingredients comprise copper oxide. The active ingredients account for 1% to 50% of the mass percentage of the organic soil-loaded copper catalyst in terms of copper oxide.

6. The method for preparing a catalyst for preparing cyclohexanol by dehydrogenation of cyclohexanol to cyclohexanone according to claim 5, characterized in that: The silane coupling agent is one of n-alkyl trimethoxysilane, γ-aminopropyl triethoxysilane and γ-methacryloxypropyl trimethoxysilane, wherein n=12, 14 or 16.

7. The method for preparing a catalyst for preparing cyclohexanol by dehydrogenation of cyclohexanol according to claim 5, characterized in that: The alkaline solution is one of sodium carbonate or sodium hydroxide.

8. The method for preparing a catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol according to claim 5, characterized in that: The copper salt solution is one of a copper nitrate solution, a copper sulfate solution or a copper chloride solution with a concentration of 0.1 to 1 mol / L.

9. The method for preparing a catalyst for preparing cyclohexanone by dehydrogenating cyclohexanol according to claim 5, characterized in that: The amount of the copper salt solution added is calculated based on the mass percentage of the active ingredient in terms of copper oxide to the copper catalyst supported by the organic soil, and the calculation formula is as follows: in, is the amount of copper in the copper salt solution, m1 is the mass of the organic soil carrier, wt% is the mass percentage of copper oxide, M (CuO) is the molar mass of copper oxide.

10. The method for preparing a catalyst for preparing cyclohexanone by dehydrogenation of cyclohexanol according to claim 5, characterized in that: The molar ratio of the alkaline solution to the copper salt solution is (1.5-2):1.

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