Method for synthesizing hexamethyleneimine from 1, 6-hexanediol through direct hydrogen ammoniation

Abstract

The method comprises the following steps: filling a high-pressure fixed bed reactor with a certain amount of a catalyst, reducing the catalyst by hydrogen in advance, enabling raw materials 1, 6-hexanediol, a solvent, liquid ammonia and hydrogen to pass through a bed layer filled with the catalyst, controlling the temperature of the catalyst bed layer, the reaction pressure and the weight hourly space velocity of the materials, and carrying out direct hydrogenation ammoniation on the raw materials to synthesize cycloheximine. Carrying out selective hydrogen ammonification on 1, 6-hexanediol to continuously prepare cycloheximine; the cheap transition metal supported catalyst comprises a main catalytic active component and a carrier. The method has the advantages of production process simplification, wide raw material source, production and separation cost reduction, resource utilization rate improvement, and solving of the problems of catalyst deactivation, reactant intermolecular condensation, and the like. And the technical problems that the yield of hexamethyleneimine is low, the process flow is complicated, the product quality is not high, the catalyst is easy to inactivate, and environmental pollution is easy to generate after-treatment of the product in China at present can be solved.

Description

Technical Field

[0001] The present invention relates to a method for synthesizing cyclohexylimine, and in particular to a method for directly hydroaminating 1,6 - hexanediol to synthesize cyclohexylimine. Background Art

[0002] Cyclohexylimine is a typical alicyclic amine organic amine, a transparent liquid with an ammonia - like odor. It is an important fine - chemical synthesis intermediate and is widely used in industries such as medicine, pesticides, rubber, and three - waste treatment. It can also be directly used to prepare soda ash, photographic developers, rubber vulcanizing agents, resin additives, rust inhibitors, petroleum product additives, etc.

[0003] US3198786A discloses an internally absorbed selective and highly effective herbicide - molinate, which is prepared by a phosgene method, a carbon disulfide method or a carbonyl sulfide method using cyclohexylimine as a raw material and is widely used worldwide. In addition, Zha et al. (G.F. Zha, K.P. Rakesh, H.M. Manukumar, et al. Pharmaceutical significance of azepane based motifs for drug discovery: A critical review. Eur. J. Med. Chem. 2019, 162, 465 - 494.) reviewed 62 drug patents derived from cyclohexylimine as a parent. These approved drugs include: antihistamines (amisidone, cetirizine), cannabinoid receptors (cannabidiol), antidiabetic drugs (glibepide, tolazamide, glyclopyramide, piremecillin), vasodilators (cetiedil), etc. In recent years, researchers have also developed other uses of cyclohexylimine, such as: combining with alkylaluminum to form metal - organic compounds, ionic liquids with imine - containing nitrogen heterocycles as cations, and template agents for titanium - silicon molecular sieves or silicon - aluminum molecular sieves. The continuous development of these downstream products brings great development opportunities to cyclohexylimine, and its demand increases year by year.

[0004] At present, there are mainly three ways to industrially obtain cyclohexylamine. One is to recover it as a by-product in the process of synthesizing hexamethylenediamine. The other two are the 1,6-hexanediamine method and the caprolactam method. Among them, the recovery route as a by-product in the hexamethylenediamine process has been used until now. CN117945922A and CN117945924A disclose a method of separating and recycling cyclohexylamine-containing materials after ammoniating 1,6-hexanediol with ammonia to adjust the co-production of hexamethylenediamine and cyclohexylamine. However, this method still cannot efficiently obtain cyclohexylamine, and the highest yield is only 14.6%. In the early 19th century, a method of preparing cyclohexylamine by hydrogenation dehydrogenation cyclization reduction of 1,6-hexanediamine was also developed. US4001213A discloses a method of catalytically reacting 1,6-hexanediamine in the gas phase using nickel, copper, cobalt, and iron as catalysts to prepare cyclohexylamine; EP372492A3 discloses a method of preparing cyclohexylamine from a gas-phase mixture of 1,6-hexanediamine, water, and hydrogen under the catalysis of solid palladium. However, a key technical problem faced by this route is to inhibit intermolecular condensation. The polyamine generated by intermolecular condensation will, on the one hand, adsorb on the catalyst, resulting in a decrease in activity and a shortening of the service life, and on the other hand, it will also reduce the product selectivity. No breakthrough progress has been made on this route in recent years. Currently, industrial production of cyclohexylamine mainly uses the caprolactam reduction method. BASF discloses in US4786727A that ε-caprolactam is directly hydrogenated under atmospheric pressure in a fixed-bed reactor using a copper catalyst supported on alumina, and cyclohexylamine is separated by a multi-stage cooling method, obtaining a 67% conversion rate of ε-caprolactam and a 97%-98% selectivity of cyclohexylamine. Although the source of ε-caprolactam is stable and abundant, catalytic reduction of amides will still produce inevitable side reactions, including ring cleavage, polymerization of amides to form polyamides, and the generated 6-aminocaproic acid is likely to poison the catalyst, resulting in serious deactivation of the catalyst. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art, especially the deficiencies of low cyclohexylamine yield, complex process flow, and easy deactivation of the catalyst in the prior art, and provide a method for directly synthesizing cyclohexylamine by catalytic hydroamination of 1,6-hexanediol with a relatively high cyclohexylamine yield and a relatively simple process flow, using a cheap transition metal-supported catalyst, and at the same time, the problem of catalyst deactivation can also be solved.

[0006] The technical solution adopted by the present invention to solve its technical problem is a method for directly synthesizing cyclohexylamine by catalytic hydroamination of 1,6-hexanediol. Using 1,6-hexanediol as a raw material and a cheap transition metal-supported catalyst, 1,6-hexanediol is directly aminated in one step to synthesize cyclohexylamine through ammonia and hydrogen.

[0007] Furthermore, the object of the present invention is achieved in the following manner: A certain amount of catalyst is filled in a high-pressure fixed-bed reactor. After the catalyst is pre-reduced with hydrogen, raw materials 1,6-hexanediol, solvent, liquid ammonia and hydrogen are passed through the bed layer filled with the above-mentioned catalyst, and the temperature of the catalyst bed layer, reaction pressure, and weight hourly space velocity of the material are controlled to continuously prepare cyclohexylimine by selective hydroamination of 1,6-hexanediol.

[0008] Furthermore, the operation of pre-reducing the catalyst with hydrogen is as follows: The catalyst is heated up and reduced with hydrogen for more than 2 h. More preferably, the temperature for pre-reducing the catalyst with hydrogen is 150 - 500 °C, but preferably 300 - 500 °C. The volume ratio of the hydrogen flow rate required for catalyst reduction to the catalyst volume can be 5 - 45 min -1 , but preferably 15 - 30 min -1 .

[0009] Furthermore, the solvent is preferably 1,4-dioxane.

[0010] Furthermore, the reaction temperature can be 100 - 450 °C, and preferably the reaction is carried out between 200 - 300 °C. At the same time, the reaction time for the catalyst to maintain its activity can be more than 0.1 h, and can be 0.1 - 3000 h, but preferably 1 - 2500 h, more preferably 2 - 48 h. The reaction pressure is from atmospheric pressure to 8 MPa, but preferably 1 MPa - 3 MPa. The weight hourly space velocity of the material can be 0.1 - 10 h -1 , but preferably 0.5 - 5 h -1 .

[0011] Furthermore, the flow rate ratio of hydrogen to liquid ammonia can be 300 - 5400, but preferably 900 - 3000. The concentration of 1,6-hexanediol (concentration in the solvent) can be 0.1 - 5 mol / L, but preferably 0.5 - 2 mol / L. The reaction time for catalyst reduction can be 0.1 - 6 h, but preferably 1 - 3 h.

[0012] Furthermore, the molar ratio of 1,6-hexanediol to liquid ammonia can be 0.001 - 0.5, but preferably 0.01 - 0.1.

[0013] The cheap transition metal-supported catalyst includes a main catalytic active component and a support. A co-catalytic active component may also be included.

[0014] Furthermore, the main catalytic active component is at least one of V, Fe, Co, Ni, Cu, Zn, etc.

[0015] Furthermore, when preparing the cheap transition metal-supported catalyst, the raw materials use compounds of the main catalytic active component, specifically at least one of chlorides, bromides, nitrates, acetates, sulfates, oxalates, acetylacetonate complexes, etc. of the main catalytic active component.

[0016] Further, the carrier is Al 2 O 3 , SiO 2 , TiO 2 , ZSM-5, SBA-15, MCM-41, activated carbon, or at least one of them.

[0017] Further, the mass ratio of the main catalytic active component to the carrier is (0.1-40):1.

[0018] Further, the co-catalytic active component is a second inexpensive transition metal oxide different from the main catalytic active component, and is at least one of V, Fe, Co, Ni, Cu, Zn, etc.

[0019] Further, when preparing the inexpensive transition metal supported catalyst, the raw material uses the compound of the co-catalytic active component, specifically at least one of the chloride, bromide, nitrate, acetate, sulfate, oxalate, acetylacetonate complex of the co-catalytic active component.

[0020] Further, when the main catalytic active component of the catalyst is Cu, V 2 O 5 , Fe 2 O 3 , Fe 3 O 4 , Co 2 O 3 , NiO, ZnO and other co-catalysts are derived from the corresponding chlorides, bromides, nitrates, acetates, sulfates, oxalates and acetylacetonate complexes, and the catalyst support is Al 2 O 3 , SiO 2 , TiO 2 , ZSM-5, SBA-15, MCM-41, activated carbon, or a mixture of one or more of them.

[0021] The first preparation method of the inexpensive transition metal supported catalyst is to prepare a catalyst with a single active component by in-situ alkali precipitation method, including the following steps:

[0022] (1) Determine the mass ratio of the main catalytic active component, the carrier, and the co-catalytic active component, and name the catalyst the main catalytic active component x / carrier; x represents that the mass ratio of the main catalytic active component to the carrier is x / 100;

[0023] (2) Dissolve the compound of the main catalytic active component in water (the amount of water should be appropriate to dissolve the compound of the main catalytic active component), stir to form a transparent solution, and then add the carrier precursor; then add water to dissolve it, and raise the temperature (preferably raise the temperature to 40 - 60 °C;

[0024] (3) Stir for a period of time (preferably 10 - 20 minutes), and then dropwise add an alkaline solution to make the pH of the mixed solution 9 - 10;

[0025] (4) Age for a period of time at a certain temperature, filter, dry overnight at a certain temperature, and calcine; thus obtained.

[0026] Furthermore, in step (2), the carrier precursors corresponding to each carrier are: Al 2 O 3 The corresponding carrier precursor is at least one of aluminum sulfate, aluminum nitrate, aluminum chloride, and sodium metaaluminate; SiO 2 The corresponding carrier precursor is tetrabutyl orthosilicate; TiO 2 The corresponding carrier precursor is tetrabutyl titanate; the carrier precursor corresponding to ZSM - 5 is a commercially available ZSM - 5 product, the carrier precursor corresponding to SBA - 15 is a commercially available SBA - 15 product, the carrier precursor corresponding to MCM - 41 is a commercially available MCM - 41 product, and the carrier precursor corresponding to activated carbon is a commercially available activated carbon product. The addition amount of the carrier precursor is determined according to the amount of the carrier in the catalyst.

[0027] Furthermore, in step (3), the alkaline solution is preferably at least one of sodium carbonate solution, potassium carbonate solution, and ammonia water. The concentration of the alkaline solution is preferably 1 - 3 mol / L.

[0028] Furthermore, in step (4), the aging time is 2 - 15 hours, dry overnight at 40 - 180 °C, and calcine at 300 - 1000 °C for 1 - 20 hours. It is preferably aged at 40 - 60 °C for 6 - 8 h, filtered and dried overnight at 60 - 70 °C, and calcined at 450 - 550 °C for 4 - 10 h.

[0029] The second preparation method of the cheap transition metal - supported catalyst is to prepare a catalyst with two active components by in - situ alkali precipitation method, including the following steps:

[0030] (1) Determine the mass ratio of the main catalytic active component, the co - catalytic active component, and the carrier, and name the catalyst as the main catalytic active component x co - catalytic active component y / carrier; x represents the mass ratio of the main catalytic active component to the carrier as x / 100; y represents the mass ratio of the co - catalytic active component to the carrier as y / 100;

[0031] (2) Dissolve the compound of the main catalytic active component and the compound of the co-catalytic active component in water (the amount of water should be appropriate to dissolve the compound of the main catalytic active component and the compound of the co-catalytic active component), stir to form a transparent solution, and then add the carrier precursor; add water again to dissolve it, and raise the temperature (preferably raise the temperature to 40 - 60 °C);

[0032] (3) Stir for a period of time (preferably 10 - 20 minutes), and then dropwise add an alkaline solution to make the pH of the mixed solution 9 - 10;

[0033] (4) Age for a period of time at a certain temperature, filter, dry overnight at a certain temperature, and calcine; thus obtained.

[0034] Furthermore, in step (2), the carrier precursors corresponding to each carrier are: Al 2 O 3 The corresponding carrier precursors are at least one of aluminum sulfate, aluminum nitrate, aluminum chloride, and sodium meta-aluminate; SiO 2 The corresponding carrier precursor is tetrabutyl orthosilicate; TiO 2 The corresponding carrier precursor is tetrabutyl titanate; the carrier precursor corresponding to ZSM-5 is a commercially available ZSM-5 product, the carrier precursor corresponding to SBA-15 is a commercially available SBA-15 product, the carrier precursor corresponding to MCM-41 is a commercially available MCM-41 product, and the carrier precursor corresponding to activated carbon is a commercially available activated carbon product. The addition amount of the carrier precursor is determined according to the amount of the carrier in the catalyst.

[0035] Furthermore, in step (3), the alkaline solution is preferably at least one of sodium carbonate solution, potassium carbonate solution, and ammonia water. The concentration of the alkaline solution is preferably 1 - 3 mol / L.

[0036] Furthermore, in step (4), the aging time is 2 - 15 hours, dry overnight at 40 - 180 °C, and calcine at 300 - 1000 °C for 1 - 20 hours. It is preferably aged at 40 - 60 °C for 6 - 8 h, filtered and dried overnight at 60 - 70 °C, and calcined at 450 - 550 °C for 4 - 10 h.

[0037] Specifically, a method for preparing a single transition metal catalyst by in-situ alkali precipitation method, taking Cu as an example, includes the following steps: a) Dissolve a certain mass of copper acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add tetrabutyl titanate (calculate the titanium content according to the amount of titanium dioxide). b) Add ultrapure water again to dissolve it and then raise the temperature; c) Stir, and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter and dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to Cu, TiO 2The mass ratio is used to name the catalyst as Cu x / TiO 2 。x represents the mass ratio of Cu and TiO 2 is x / 100.

[0038] Specifically, a method for preparing a catalyst containing a promoter by in-situ alkali precipitation method, taking Cu and NiO as examples, includes the following steps: a) Dissolve copper acetate and nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add tetrabutyl titanate. b) Add ultrapure water again and then raise the temperature to 50 °C. c) Stir, and then dropwise add 1 mol / L Na 2 CO 3 aqueous solution to make the pH of the mixed solution 9-10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to the mass ratio of Cu, NiO, and TiO 2 the catalyst is named Cu x Ni y / TiO 2 。x represents the mass ratio of Cu and TiO 2 is x / 100. y represents the mass ratio of NiO and TiO 2 is y / 100.

[0039] The present invention uses inexpensive transition metals as the main catalytic active components, Al 2 O 3 , SiO 2 , TiO 2 , ZSM-5, SBA-15, MCM-41, activated carbon, etc. as carriers, and uses the second inexpensive transition metal oxide as the promoter catalytic active component to regulate the electron flow interaction between the main catalytic active component and the carrier, obtaining a supported multi-phase catalyst containing an inexpensive transition metal or a copper-based metal, which is used for the method of catalytic hydroamination for directly synthesizing cyclohexylimine from 1,6-hexanediol.

[0040] If the catalytic active center is a single inexpensive transition metal, the active center precursor components are at least one of chlorides, bromides, nitrates, acetates, sulfates, oxalates, and acetylacetonate complexes of V, Fe, Co, Ni, Cu, and Zn. If the main active center is Cu, the active center precursor components are at least one of chlorides, bromides, nitrates, acetates, sulfates, oxalates, and acetylacetonate complexes of Cu, preferably at least one of acetates, oxalates, and acetylacetonate complexes; V that regulates the electron flow interaction between the metal and the carrier 2 O 5 , Fe 2 O 3 , Fe 3 O 4 , Co2 O 3 、 NiO, ZnO and other cocatalysts are derived from corresponding chlorides, bromides, nitrates, acetates, sulfates, oxalates, acetylacetonate complexes, preferably acetates, oxalates, acetylacetonate complexes; the catalyst support is Al 2 O 3 、 SiO 2 、 TiO 2 、 ZSM-5, SBA-15, MCM-41 and activated carbon, or a mixture of one or more of them. Among them, the ZSM-5, SBA-15, and MCM-41 supports are activated in a muffle furnace before use, preferably at 400-800 °C (more preferably 600 °C) for 2-8 h (more preferably 4 h).

[0041] The present invention relates to a method for preparing a series of supported heterogeneous catalysts containing inexpensive transition metals or copper-based main metals by in-situ alkali precipitation method, using inexpensive transition metals as the main catalytic active components, and Al 2 O 3 、 SiO 2 、 TiO 2 、 ZSM-5, SBA-15, MCM-41 and activated carbon as supports, and using the second inexpensive transition metal oxide as the cocatalytic active component to regulate the electron flow interaction between the main catalytic active component and the support, for the method of catalytic hydroamination of 1,6-hexanediol to directly synthesize cyclohexylimine.

[0042] The present invention uses widely sourced 1,6-hexanediol and ammonia as raw materials, and uses inexpensive transition metals as catalysts under gas-phase conditions to selectively catalytically synthesize cyclohexylimine, which is an economical and green process. It can solve the technical problems of low production of cyclohexylimine in China at present, complex process flow, low product quality, easy deactivation of catalysts, and environmental pollution easily generated in product post-treatment. The present invention uses 1,6-hexanediol and ammonia as raw materials to develop a green technical route for catalytic hydroamination of 1,6-hexanediol and ammonia to highly selectively prepare cyclohexylimine, which can simplify the production process, has wide raw material sources, reduce production and separation costs, improve resource utilization rate, and at the same time can also solve problems such as catalyst deactivation and intermolecular condensation of reactants. Detailed implementation mode

[0043] The following further elaborates on the present invention with specific examples.

[0044] Example 1: The catalyst Cu 20 / TiO 2Charge the reaction tube, heat it up to 300 °C, and reduce it with hydrogen at 30 mL / min for 2 h. Subsequently, 1,6-hexanediol (concentration 0.5 mol / L) completely dissolved in 1,4-dioxane was continuously injected by a double-plunger micro pump (WHSV (weight hourly space velocity) was 1.1 h -1 ), liquid ammonia was continuously injected by another double-plunger micro pump (3 mL / h), and the molar ratio of 1,6-hexanediol to liquid ammonia was 0.01; after mixing, it was vaporized through the preheating section and entered the Cu 20 / TiO 2 catalyst bed for reaction. The reaction temperature was 220 °C, the reaction hydrogen flow rate was 90 mL / min, the pressure was 2 MPa, and the product was condensed by a water bath and entered the collection bottle. After the reaction started, samples of the product were taken every 2 h to analyze the product composition. The average conversion rate of 1,6-hexanediol was 92.6% and the average selectivity for cyclohexylamine was 71.1% when the reaction time was 20 h as determined by gas chromatography analysis.

[0045] Cu 20 / TiO 2 Preparation method of the catalyst, comprising the following steps: a) Dissolve 2.5 g of copper acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 15.34 g of tetrabutyl titanate. b) Add ultrapure water to dissolve it and then heat it up to 60 °C; c) Stir and add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) Name the catalyst Cu 2 / TiO 20 according to the mass ratio of Cu and TiO 2 . 20 indicates that the mass ratio of Cu to TiO 2 is 20 / 100.

[0046] Example 2: The steps are the same as in Example 1, except that the catalyst is Ni 20 / TiO 2 , the conversion rate of 1,6-hexanediol is 20.5%, and the selectivity for cyclohexylamine is 62.0%.

[0047] The preparation method of the Ni 20 / TiO 2 catalyst, comprising the following steps: a) Dissolve 2.4 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water to dissolve it and then heat it up to 40 °C; c) Stir and add an aqueous solution of Na 2 CO 3The aqueous solution makes the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, dry overnight at 60 °C after filtration, and calcine at 450 °C for 4 h. e) According to the mass ratio of Ni and TiO 2 The catalyst is named Ni 20 / TiO 2 . 20 indicates that the mass ratio of Ni and TiO 2 is 20 / 100.

[0048] Example 3: The steps are the same as those in Example 1, except that the catalyst is Zn 20 / TiO 2 , the conversion rate of 1,6 - hexanediol is 55.4%, and the selectivity of cyclohexylimine is 67.7%.

[0049] The preparation method of the Zn 20 / TiO 2 catalyst includes the following steps: a) Dissolve 2.2 g of zinc acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, dry overnight at 60 °C after filtration, and calcine at 450 °C for 4 h. e) According to the mass ratio of Zn and TiO 2 , the catalyst is named Zn 20 / TiO 2 . 20 indicates that the mass ratio of Zn and TiO 2 is 20 / 100.

[0050] Example 4: The steps are the same as those in Example 1, except that the catalyst is Co 20 / TiO 2 , the conversion rate of 1,6 - hexanediol is 68.8%, and the selectivity of cyclohexylimine is 54.2%.

[0051] The preparation method of the Co 20 / TiO 2 catalyst includes the following steps: a) Dissolve 2.5 g of cobalt nitrate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water to dissolve it and then heat it up to 40 °C; c) Stir and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, dry overnight at 60 °C after filtration, and calcine at 450 °C for 4 h. e) According to the mass ratio of Co and TiO 2 , the catalyst is named Co 20 / TiO 2。The mass ratio of Co to TiO 2 is 20 / 100.

[0052] Example 5: The procedure is the same as in Example 1, except that the catalyst is Fe 20 / TiO 2 . The conversion rate of 1,6 - hexanediol is 54.2%, and the selectivity for cyclohexylamine is 35.1%.

[0053] The preparation method of the said Fe 20 / TiO 2 catalyst comprises the following steps: a) Dissolve 5.8 g of ferric nitrate nonahydrate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water again to dissolve it and then heat to 50 °C; c) Stir and add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) Name the catalyst as Co 2 / TiO 20 according to the mass ratio of Co to TiO 2 . The mass ratio of 20 represents that of Co to TiO 2 is 20 / 100.

[0054] Example 6: The procedure is the same as in Example 1, except that the catalyst is Cu 20 / Al 2 O 3 . The conversion rate of 1,6 - hexanediol is 81.2%, and the selectivity for cyclohexylamine is 61.5%.

[0055] The preparation method of the said Cu 20 / Al 2 O 3 catalyst comprises the following steps: a) Dissolve 2.5 g of copper acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 4 g of commercially available Al 2 O 3 ; b) Add ultrapure water again to dissolve it and then heat to 50 °C; c) Stir and add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) Name the catalyst as Cu 2 O 3 / Al 20 O 2 according to the mass ratio of Cu to Al 3 . The mass ratio of 20 represents that of Cu to Al 2 O 3The mass ratio is 20 / 100.

[0056] Example 7: The steps are the same as those in Example 1, except that the catalyst is Cu 20 / ZSM-5. The conversion rate of 1,6-hexanediol is 74.4%, and the selectivity of cyclohexylimine is 69.5%.

[0057] The described Cu 20 / ZSM-5 catalyst preparation method includes the following steps: a) Dissolve 2.5 g of copper acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 4 g of commercially available ZSM-5; b) Add ultrapure water to dissolve it and then heat it to 50 °C; c) Stir and dropwise add Na 2 CO 3 aqueous solution to make the pH of the mixed solution 9-10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) Name the catalyst Cu 20 / ZSM-5 according to the mass ratio of Cu and ZSM-5. 20 indicates that the mass ratio of Cu and ZSM-5 is 20 / 100.

[0058] Example 8: The steps are the same as those in Example 1, except that the catalyst is Cu 20 / MCM-41. The conversion rate of 1,6-hexanediol is 82.1%, and the selectivity of cyclohexylimine is 79.6%.

[0059] The described Cu 20 / MCM-41 catalyst preparation method includes the following steps: a) Dissolve 2.5 g of copper acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 4 g of commercially available MCM-41; b) Add ultrapure water to dissolve it and then heat it to 50 °C; c) Stir and dropwise add Na 2 CO 3 aqueous solution to make the pH of the mixed solution 9-10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) Name the catalyst Cu 20 / MCM-41 according to the mass ratio of Cu and MCM-41. 20 indicates that the mass ratio of Cu and MCM-41 is 20 / 100.

[0060] Example 9: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the conversion rate of 1,6-hexanediol is 100%, and the selectivity of cyclohexylimine is 80.6%.

[0061] The described Cu 9 Ni 6 / TiO 2Preparation method of catalyst, comprising the following steps: a) Dissolve 1.1 g of copper acetate and 0.6 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir and add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9-10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to the mass ratio of Cu, TiO 2, NiO, TiO 2 , name the catalyst Cu 9 Ni 6 / TiO 2 . 9 means the mass ratio of Cu, TiO 2 is 9 / 100, and 6 means the mass ratio of NiO, TiO 2 is 6 / 100.

[0062] Example 10: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the reaction temperature is 215 °C, the conversion rate of 1,6-hexanediol is 100%, and the selectivity of cyclohexylimine is 89.6%.

[0063] Example 11: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the reaction temperature is 200 °C, the conversion rate of 1,6-hexanediol is 20.5%, and the selectivity of cyclohexylimine is 98.2%.

[0064] Example 12: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the reaction temperature is 215 °C, the hydrogen flow rate is 60 mL / min, the conversion rate of 1,6-hexanediol is 100%, and the selectivity of cyclohexylimine is 98.0%.

[0065] Example 13: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the reaction temperature is 215 °C, the hydrogen flow rate is 20 mL / min, the conversion rate of 1,6-hexanediol is 98.2%, and the selectivity of cyclohexylimine is 75.5%.

[0066] Example 14: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni6 / TiO 2 , with a hydrogen flow rate of 60 mL / min and a WHSV of 2.2 h -1 , the conversion rate of 1,6 - hexanediol is 100%, and the selectivity of cyclohexylimine is 94.6%.

[0067] Example 15: The steps are the same as in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , with a hydrogen flow rate of 60 mL / min and a WHSV of 0.55 h -1 , the conversion rate of 1,6 - hexanediol is 100%, and the selectivity of cyclohexylimine is 93.0%.

[0068] Example 16: The steps are the same as in Example 1, except that the catalyst is Cu 4 Ni 6 / TiO 2 , with a hydrogen flow rate of 60 mL / min, the conversion rate of 1,6 - hexanediol is 84.1%, and the selectivity of cyclohexylimine is 90.2%.

[0069] The Cu 4 Ni 6 / TiO 2 Preparation method of the catalyst, including the following steps: a) Dissolve 0.5 g of copper acetate and 0.6 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to the mass ratio of Cu, TiO 2, NiO, TiO 2 , name the catalyst Cu 4 Ni 6 / TiO 2 . 4 represents that the mass ratio of Cu, TiO 2 is 4 / 100, and 6 represents that the mass ratio of NiO, TiO 2 is 6 / 100.

[0070] Example 17: The steps are the same as in Example 1, except that the catalyst is Cu 14 Ni 6 / TiO 2 , with a hydrogen flow rate of 60 mL / min, the conversion rate of 1,6 - hexanediol is 100%, and the selectivity of cyclohexylimine is 97.9%.

[0071] The Cu14 Ni 6 / TiO 2 Preparation method of the catalyst, comprising the following steps: a) Dissolve 1.8 g of copper acetate and 0.6 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir, dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to the mass ratio of Cu, TiO 2, NiO, TiO 2 , name the catalyst Cu 14 Ni 6 / TiO 2 . 14 indicates that the mass ratio of Cu, TiO 2 is 14 / 100, and 6 indicates that the mass ratio of NiO, TiO 2 is 6 / 100.

[0072] Example 18: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 3 / TiO 2 , the hydrogen flow rate is 60 mL / min, the conversion rate of 1,6 - hexanediol is 100%, and the selectivity of cyclohexylamine is 85.4%.

[0073] The preparation method of the Cu 9 Ni 3 / TiO 2 catalyst, comprising the following steps: a) Dissolve 1.1 g of copper acetate and 0.3 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 17.0 g of tetrabutyl titanate; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir, dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to the mass ratio of Cu, TiO 2, NiO, TiO 2 , name the catalyst Cu 9 Ni 3 / TiO 2 . 9 indicates that the mass ratio of Cu, TiO 2 is 9 / 100, and 3 indicates that the mass ratio of NiO, TiO 2 is 3 / 100.

[0074] Example 19: The steps are the same as those in Example 1, except that the catalyst is Cu9 Ni 6 / SiO 2 With a hydrogen flow rate of 60 mL / min, the conversion rate of 1,6-hexanediol was 100%, and the selectivity for cyclohexylamine was 92.1%.

[0075] The described Cu 9 Ni 6 / SiO 2 The preparation method of the catalyst includes the following steps: a) Dissolve 1.1 g of copper acetate and 0.6 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 4 g of commercially available SiO 2 ; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) Name the catalyst Cu 2, NiO, SiO 2 / SiO according to the mass ratio of Cu, SiO 9 Ni 6 / SiO 2 . 9 indicates that the mass ratio of Cu, SiO 2 is 9 / 100, and 6 indicates that the mass ratio of NiO, SiO 2 is 6 / 100.

[0076] Example 20: The steps are the same as in Example 1, except that the catalyst is Cu 9 Ni 6 / activated carbon, with a hydrogen flow rate of 60 mL / min, the conversion rate of 1,6-hexanediol was 78.2%, and the selectivity for cyclohexylamine was 82.1%.

[0077] The described Cu 9 Ni 6 / activated carbon catalyst preparation method includes the following steps: a) Dissolve 1.1 g of copper acetate and 0.6 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 4 g of commercially available activated carbon; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) Name the catalyst Cu , NiO, activated carbon according to the mass ratio of Cu, activated carbon 9 Ni 6 / activated carbon. 9 indicates that the mass ratio of Cu, activated carbon is 9 / 100, and 6 indicates that the mass ratio of NiO, activated carbon is 6 / 100.

[0078] Example 21: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the reduction time of the catalyst is 1 h, the reaction temperature is 215 °C, the hydrogen flow rate is 60 mL / min, the conversion rate of 1,6 - hexanediol is 92.2%, and the selectivity of cyclohexylimine is 96.8%.

[0079] Example 22: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the reduction temperature of the catalyst is 400 °C, the reaction temperature is 215 °C, the hydrogen flow rate is 60 mL / min, the conversion rate of 1,6 - hexanediol is 100%, and the selectivity of cyclohexylimine is 97.1%.

[0080] Example 23: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 , the reduction flow rate of the catalyst is 60 mL / min, the reaction temperature is 215 °C, the hydrogen flow rate is 60 mL / min, the conversion rate of 1,6 - hexanediol is 100%, and the selectivity of cyclohexylimine is 97.5%.

[0081] Example 23: The steps are the same as those in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 -SiO 2 , the reaction temperature is 215 °C, the hydrogen flow rate is 60 mL / min, the conversion rate of 1,6 - hexanediol is 100%, and the selectivity of cyclohexylimine is 94.2%.

[0082] The described Cu 9 Ni 6 / TiO 2 -SiO 2 Preparation method of the catalyst, including the following steps: a) Dissolve 1.1 g of copper acetate and 0.6 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 2 g of tetrabutyl titanate and 2 g of commercially available SiO 2 ; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to Cu, TiO 2 -SiO 2, NiO, TiO2 -SiO 2 mass ratio, the catalyst is named Cu 9 Ni 6 / TiO 2 -SiO 2 . 9 represents the mass ratio of Cu, TiO 2 -SiO 2 is 9 / 100, and 6 represents the mass ratio of NiO, TiO 2 -SiO 2 is 6 / 100.

[0083] Example 24: The procedure is the same as in Example 1, except that the catalyst is Cu 9 Ni 6 / TiO 2 -ZSM-5, the reaction temperature is 215 °C, the hydrogen flow rate is 60 mL / min, the conversion rate of 1,6-hexanediol is 100%, and the selectivity of cyclohexylimine is 95.4%.

[0084] The described Cu 9 Ni 6 / TiO 2 -ZSM-5 catalyst preparation method includes the following steps: a) Dissolve 1.1 g of copper acetate and 0.6 g of nickel acetate in ultrapure water, stir at room temperature to form a transparent solution, and then add 2 g of tetrabutyl titanate and 2 g of commercially available ZSM-5; b) Add ultrapure water to dissolve it and then heat it up to 50 °C; c) Stir and dropwise add an aqueous solution of Na 2 CO 3 to make the pH of the mixed solution 9 - 10. d) Age at 50 °C for 6 h, filter, dry overnight at 60 °C, and calcine at 450 °C for 4 h. e) According to the mass ratio of Cu, TiO 2 -SiO 2, NiO, TiO 2 -ZSM-5, the catalyst is named Cu 9 Ni 6 / TiO 2 -ZSM-5. 9 represents the mass ratio of Cu, TiO 2 -ZSM-5 is 9 / 100, and 6 represents the mass ratio of NiO, TiO 2 -ZSM-5 is 6 / 100.

Claims

1. A method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol, characterized in that: Using 1,6-hexanediol as raw material, using cheap transition metal supported catalyst, 1,6-hexanediol is directly aminized into cyclohexylimide in one step by ammonia and hydrogen; Specifically, the method comprises the following steps: a certain amount of catalyst is filled in a high-pressure fixed bed reactor, the catalyst is pre-reduced by hydrogen, raw materials 1,6-hexanediol, solvent, liquid ammonia and hydrogen are passed through a bed layer containing the catalyst, the catalytic reaction temperature, reaction pressure and material weight hourly space velocity are controlled, and 1,6-hexanediol is selectively hydroaminated to continuously prepare cycloheximide; The cheap transition metal supported catalyst comprises a main catalytic active component and a carrier.

2. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to claim 1, characterized in that: The operation of pre-reducing the catalyst with hydrogen is as follows: heating the catalyst and reducing it with hydrogen for more than 2 hours; and / or, the solvent is 1,4-dioxane; and / or, the catalytic reaction temperature is 100-450°C; and / or, the reaction pressure is normal pressure to 8 MPa; and / or, the material weight hourly space velocity is 0.1-10 h -1 ; and / or, the flow ratio of hydrogen to liquid ammonia is 300-5400; and / or, the concentration of 1,6-hexanediol is 0.1-5 mol / L; and / or, the catalyst reduction reaction time is 0.1-6h; and / or, the amount ratio of 1,6-hexanediol to liquid ammonia is 0.001-0.

5.

3. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to claim 2, characterized in that: The temperature of the hydrogen pre-reduction catalyst is 150-500°C; and / or the ratio of the hydrogen flow rate to the catalyst volume required for catalyst reduction is 5-45min -1 ; and / or, the reaction temperature is 200-300°C; and / or, the reaction pressure is 1MPa-3MPa; and / or, the material weight hourly space velocity is 0.5-5h -1 ; and / or, the flow ratio of hydrogen to liquid ammonia is 900-3000; and / or, the concentration of 1,6-hexanediol is 0.5-2 mol / L; and / or, the catalyst reduction reaction time is 1-3h; and / or, the amount ratio of 1,6-hexanediol to liquid ammonia is 0.01-0.

1.

4. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to claim 1 or 2, characterized in that: The cheap transition metal supported catalyst also includes a catalytically active component.

5. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to any one of claims 1 to 4, characterized in that: The main catalytic active component is at least one of V, Fe, Co, Ni, Cu, and Zn; and / or, when preparing a cheap transition metal supported catalyst, the raw material is at least one of the chloride, bromide, nitrate, acetate, sulfate, oxalate, and acetylacetone complex of the main catalytic active component; and / or, the carrier is at least one of Al2O3, SiO2, TiO2, ZSM-5, SBA-15, MCM-41, and activated carbon.

6. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to claim 5, characterized in that: The mass ratio of the main catalytic active component to the carrier is (0.1-40):

1.

7. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to claim 4, characterized in that: The co-catalytic active component is a second cheap transition metal oxide different from the main catalytic active component, which is at least one of V, Fe, Co, Ni, Cu, and Zn; and / or, when preparing a cheap transition metal supported catalyst, the raw material is at least one of the chloride, bromide, nitrate, acetate, sulfate, oxalate, and acetylacetone complex of the co-catalytic active component.

8. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to claim 5, characterized in that: When the main catalytic active component of the catalyst is Cu, the V2O5, Fe2O3, Fe3O4, Co2O3, NiO, and ZnO co-catalysts that regulate the interaction of electron flow between metal Cu and the carrier are derived from corresponding chlorides, bromides, nitrates, acetates, sulfates, oxalates, and acetylacetone complexes, and the catalyst cross-section is a mixture of one or more of Al2O3, SiO2, TiO2, ZSM-5, SBA-15, MCM-41, and activated carbon.

9. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to any one of claims 1 to 8, characterized in that: The first method for preparing the cheap transition metal supported catalyst is to prepare a catalyst with a single active component by an in-situ alkali precipitation method, comprising the following steps: (1) Determine the mass ratio of the main catalytic active component and the carrier, and name the catalyst as the main catalytic active component x / carrier; x represents the mass ratio of the main catalytic active component to the carrier is x / 100; (2) adding water to dissolve the compound of the main catalytic active component, stirring to form a transparent solution, and then adding the carrier precursor; then adding water to dissolve it and heating it; (3) Stirring for a period of time, and then adding alkaline solution dropwise to adjust the pH of the mixed solution to 9-10; (4) aging for a period of time at a certain temperature, filtering, drying overnight at a certain temperature, and calcining; The second method for preparing the cheap transition metal supported catalyst is to prepare the catalyst of two active components by in-situ alkali precipitation method, which comprises the following steps: (1) Determine the mass ratio of the main catalytic active component, the co-catalytic active component, and the carrier, and name the catalyst the main catalytic active component x Catalytically active components y / carrier; x represents the mass ratio of the main catalytic active component to the carrier is x / 100; y represents the mass ratio of the auxiliary catalytic active component to the carrier is y / 100; (2) adding water to dissolve the compound of the main catalytic active component and the compound of the auxiliary catalytic active component, stirring to form a transparent solution, and then adding a carrier precursor; further adding water to dissolve it and heating it; (3) Stirring for a period of time, and then adding alkaline solution dropwise to adjust the pH of the mixed solution to 9-10; (4) aging for a period of time at a certain temperature, filtering, drying overnight at a certain temperature, and calcining; the product is obtained.

10. The method for synthesizing cycloheximide by direct hydroamination of 1,6-hexanediol according to claim 9, characterized in that: In step (2), the carrier precursors corresponding to each carrier are: the carrier precursor corresponding to Al2O3 is at least one of aluminum sulfate, aluminum nitrate, aluminum chloride, and sodium aluminate; the carrier precursor corresponding to SiO2 is n-butyl silicate; the carrier precursor corresponding to TiO2 is n-butyl titanate; the carrier precursor corresponding to ZSM-5 is a commercially available ZSM-5 product, the carrier precursor corresponding to SBA-15 is a commercially available SBA-15 product, the carrier precursor corresponding to MCM-41 is a commercially available MCM-41 product, and the carrier precursor corresponding to activated carbon is a commercially available activated carbon product; and / or, in step (3), the alkaline solution is at least one of sodium carbonate solution, potassium carbonate solution, and ammonia water; and / or, in step (4), the aging time is 2 to 15 hours, dried overnight at 40 to 180°C, and calcined at 300 to 1000°C for 1 to 20 hours.