Catalyst for synthesis of hexamethylene diamine from hexamethylene imine, process for the preparation thereof and process for the synthesis of hexamethylene diamine

Abstract

The present disclosure relates to a catalyst for synthesizing hexamethylenediamine from hexamethyleneimine, a preparation method of the catalyst and a method for synthesizing hexamethylenediamine. The catalyst comprises 5-98 wt% of a titanium-containing carrier, 2-30 wt% of vanadium oxide, 0-30 wt% of metal M oxide and / or 0-10 wt% of inorganic oxide, based on dry basis and the total weight of the catalyst; wherein the titanium-containing carrier comprises titanium dioxide and a titanium-containing molecular sieve; the metal M is selected from one or more of the group consisting of a VB element, a VIB element, a VIII element and a lanthanum element, and the inorganic oxide is selected from one or both of Al2O3 and SiO2. The catalyst and the synthesis method provided by the present disclosure achieve higher raw material conversion rate and target product selectivity.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of hexanediamine preparation, in particular, a catalyst for synthesizing hexanediamine from hexamethyleneimine and a preparation method thereof and a method for synthesizing hexanediamine. BACKGROUND

[0002] Hexanediamine is an important chemical raw material, which is often used to synthesize nylon 66, nylon 610, HDI and other important industrial products. All industrial hexanediamine is prepared by hydrogenation of adiponitrile.

[0003] The synthesis of hexanediamine from caprolactam is a new route. Caprolactam and ammonia undergo ammoniation and dehydration reaction under the catalysis of phosphate catalyst to generate aminocapronitrile; then aminocapronitrile undergoes catalytic hydrogenation reaction to obtain hexanediamine. Compared with the traditional production route, the caprolactam method avoids the use of hydrocyanic acid, adiponitrile and other toxic raw materials, has the characteristics of environmental friendliness, simple and safe operation, no special equipment requirement, easy industrialization production, etc., and is a green production route of hexanediamine. However, the process is still limited by raw materials, the production scale is very small, the annual production capacity is only 6000 tons, and the product is only used for the company's downstream products.

[0004] In recent years, with the rapid growth of caprolactam production capacity in China, the source problem of upstream raw material caprolactam has been solved from the source. The process of preparing hexanediamine from caprolactam was first reported by US2234566 and US2181140 patents of DuPont Company in the 1940s. The process is divided into three steps. The first step is that caprolactam and ammonia undergo ammoniation ring-opening reaction under the action of catalyst to generate 6-aminocaproyl amide, 6-aminocaproyl amide is dehydrated to remove oxygen atom to generate 6-aminocapronitrile, and then 6-aminocapronitrile is hydrogenated to obtain hexanediamine. This process was industrialized by Japan Toray in 1965, and is mainly used for the recycling of caprolactam substandard or waste nylon and other waste raw materials recovered from nylon 6 plant. Therefore, this process has not been economically viable.

[0005] US2234566 discloses a process for synthesizing 6-aminocapronitrile from caprolactam using copper supported on silica as a dehydration catalyst, and the caprolactam conversion rate is 21.7%, the 6-aminocapronitrile yield is 25%, and the patent does not disclose the yield of hexamethylenediamine. US3855267 discloses a process for synthesizing 6-aminocapronitrile from caprolactam and ammonia gas by passing the mixed gas through an aluminum phosphate catalyst, and the 6-aminocapronitrile selectivity is 87% when the ammonia / caprolactam molar ratio is 75-100. The above two methods for preparing 6-aminocapronitrile have the disadvantages of low catalyst activity and high energy consumption. CN107739318A discloses a process and device for preparing 6-aminocapronitrile from caprolactam in a liquid phase, which uses phosphoric acid or a phosphoric acid salt as a catalyst, and the yield is not high, which is about 50% according to the examples. This method has the disadvantages of complex catalyst and solvent separation, high energy consumption, and low caprolactam conversion rate. The process for synthesizing 6-aminocapronitrile from caprolactam disclosed in CN107602416A is similar to US2234566, and the reaction temperature for preparing 6-aminocapronitrile from caprolactam in a gas phase is about 350°C, and the contact time between caprolactam and ammonia gas is less than 1 second, which is difficult to control.

[0006] In summary, the existing process for synthesizing hexamethylenediamine from caprolactam amination to generate 6-aminocapronitrile and then hydrogenation of 6-aminocapronitrile to obtain hexamethylenediamine has the problems of low raw material conversion rate and low catalyst activity. SUMMARY

[0007] The purpose of the present disclosure is to provide a catalyst for synthesizing hexamethylenediamine from hexamethyleneimine, a preparation method thereof, and a method for synthesizing hexamethylenediamine, which can catalyze the synthesis of hexamethylenediamine from hexamethyleneimine, has a higher raw material conversion rate and target product selectivity, and has good catalyst stability.

[0008] To achieve the above purpose, the first aspect of the present disclosure provides a catalyst for synthesizing hexamethylenediamine from hexamethyleneimine, which comprises 5-98% by weight of a titanium-containing carrier, 2-30% by weight of vanadium oxide, 0-30% by weight of metal M oxide, and / or 0-10% by weight of inorganic oxide, based on the total weight of the catalyst; wherein the content of the titanium-containing carrier is based on the total amount of titanium dioxide; the metal M is selected from one or more of the group consisting of group VB elements, group VIB elements, group VIII elements, and lanthanum elements, and the inorganic oxide is selected from one or both of Al2O3 and SiO2.

[0009] Optionally, the catalyst comprises 20-95 wt% of the titanium-containing support, 3-20 wt% of the vanadium oxide, 0.5-10 wt% of the metal M oxide and / or 0.2-6 wt% of the inorganic oxide, based on dry basis and based on the total weight of the catalyst.

[0010] Optionally, the titanium-containing support comprises TiO2 and a titanium-containing molecular sieve; preferably, the titanium-containing molecular sieve comprises a titanium silicalite molecular sieve; the titanium silicalite molecular sieve is selected from one or more of HTS, TS-1 molecular sieve, TS-2 molecular sieve and TS-48 molecular sieve.

[0011] Preferably, the metal M is selected from one or more of tungsten, molybdenum, chromium, zinc, manganese, lanthanum and iron.

[0012] Optionally, the catalyst has a BET specific surface area of 10-200 m2 / g, a total pore volume of 0.02-0.3 mL / g and a micropore volume of 0.01-0.1 mL / g. 2 Optionally, the catalyst has a BET specific surface area of 10-200 m2 / g, a total pore volume of 0.02-0.3 mL / g and a micropore volume of 0.01-0.1 mL / g.

[0013] Optionally, the catalyst has a shape selected from one or more of a spherical shape, a strip shape, a cylindrical shape, a ring shape, a trilobal shape, a quadrilobal shape, a honeycomb shape and a butterfly shape.

[0014] The second aspect of the present disclosure provides a method for preparing a catalyst for synthesizing hexamethylene diamine from hexamethylene imine, comprising the following steps:

[0015] S1, contacting a vanadium source, water and an acid for an oxidation reaction; adding a titanium-containing support and an optional metal M source to the oxidation reaction product to obtain a mixture; and performing a first drying treatment on the mixture to obtain an intermediate solid product;

[0016] S2, sequentially performing a molding treatment, a second drying treatment and a calcination treatment on the intermediate solid product.

[0017] Optionally, in step S1, the weight ratio of water: vanadium source: acid: metal M source: titanium-containing support is (0.5-2.0):(0.05-0.2):(0.05-0.5):(0-0.5):1; preferably (0.8-1.6):(0.05-0.15):(0.1-0.3):(0.01-0.3):1.

[0018] Optionally, in step S1, the vanadium source is selected from one or more of ammonium metavanadate, sodium metavanadate and divanadium pentoxide; the acid is selected from one or more of oxalic acid, citric acid and nitric acid; the metal M source is selected from one or more of nitrate, phosphate and chloride of the metal M element; preferably selected from one or more of ammonium molybdate tetrahydrate, sodium tungstate, chromium nitrate and lanthanum nitrate.

[0019] Optionally, step S1 comprises: dissolving the vanadium source in water, then adding the acid to the vanadium source solution to perform the oxidation reaction to obtain an oxidation reaction product; adding a metal M source to the oxidation reaction product to perform a first mixing to obtain a first mixture, and the conditions of the first mixing comprise: a mixing temperature of 50-100°C and a mixing time of 60-300 min; adding the titanium-containing carrier to the first mixture to perform a second mixing to obtain a second mixture, and the conditions of the second mixing comprise: a mixing temperature of 30-80°C and a mixing time of 30-300 min; performing the first drying treatment on the second mixture, and then performing grinding to obtain the intermediate solid product; and the temperature of the first drying treatment is 80-150°C.

[0020] Optionally, the forming treatment in step S2 adopts an extrusion forming process or a rolling ball forming process; optionally, the extrusion forming process comprises the following steps: extruding and mixing the intermediate solid product with a pore-expanding agent and an auxiliary agent, and then sequentially performing the forming treatment, a second drying treatment and a calcination treatment; and optionally, the rolling ball forming process comprises the following steps: mixing the intermediate solid product with an inorganic oxide source, and then sequentially performing the forming treatment, a second drying treatment and a calcination treatment.

[0021] Optionally, the conditions of the extrusion forming process comprise: based on a dry basis and taking the added weight of the titanium-containing carrier as a reference, the added amount of the pore-expanding agent is 0.5-10 wt%, preferably 1-5 wt%; and the added amount of the auxiliary agent is 0.5-4 wt%, preferably 0.5-2 wt%; preferably, the pore-expanding agent is selected from one or more of sesbania powder, paraffin, stearic acid, glycerol, starch, polyethylene glycol, polyvinyl alcohol, polyethylene oxide, polyacrylamide, cellulose methyl ether, cellulose, polyhydric alcohol and graphite; preferably, the auxiliary agent is selected from one or more of an organic acid, an inorganic acid and an inorganic base, preferably, the auxiliary agent is selected from one or more of oxalic acid, tartaric acid, citric acid, nitric acid, hydrochloric acid, acetic acid, formic acid, ammonia, sodium hydroxide and potassium hydroxide.

[0022] Optionally, the conditions of the rolling ball forming process comprise: based on a dry basis and taking the added weight of the titanium-containing carrier as a reference, the added amount of the inorganic oxide source is 0.1-5 wt%, preferably 0.1-2.0 wt%; optionally, the added form of the inorganic oxide source comprises an inorganic oxide or an inorganic oxide precursor; preferably, the inorganic oxide is selected from one or both of Al2O3 and SiO2; and preferably, the inorganic oxide precursor is selected from one or more of an aluminum sol, a silicon sol and water glass.

[0023] Optionally, in step S2, the conditions of the second drying treatment include: a drying temperature of 80-200°C, preferably 100-150°C; a drying time of 1-10h, preferably 2-4h; and the conditions of the calcination include: a calcination temperature of 200-900°C, preferably 500-800°C; and a post-calcination time of 0.5-10h, preferably 2-4h.

[0024] The third aspect of the present disclosure provides a catalyst prepared by the method according to the second aspect of the present disclosure.

[0025] The fourth aspect of the present disclosure provides a method for synthesizing hexamethylenediamine from hexamethyleneimine amination, comprising: contacting hexamethyleneimine raw material, an amination catalyst, and ammonia gas in a reactor to perform an amination reaction; the amination catalyst comprises the catalyst according to the first aspect or the third aspect of the present disclosure.

[0026] Optionally, the conditions of the amination reaction include: a reaction temperature of 200-500°C, a weight ratio of ammonia gas to hexamethyleneimine raw material of (0.1-20):1, an ammonia gas partial pressure of 0.1-8.0MPa, and a hexamethyleneimine raw material weight hourly space velocity of 0.2-100h-1. -1 Optionally, the reactor is a fixed bed reactor; the fixed bed reactor comprises a packing layer, and the packing layer comprises the catalyst; optionally, the hexamethyleneimine raw material comprises caprolactam hydrogenation liquid; preferably, the caprolactam hydrogenation liquid comprises 10-80wt% of hexamethyleneimine and 20-90wt% of water.

[0027] By the above technical solution, the present disclosure provides a catalyst for synthesizing hexamethylenediamine from hexamethyleneimine, a preparation method of the catalyst, and a method for synthesizing hexamethylenediamine. The catalyst has high catalytic activity for the amination reaction of hexamethyleneimine raw material, can obtain high conversion rate of the hexamethyleneimine raw material and selectivity of hexamethylenediamine, and has high stability in the amination reaction and can still have high catalytic activity under long-time reaction conditions. The inorganic oxide added in the catalyst can improve the strength of the catalyst, thereby improving the service life of the catalyst; the metal M oxide added in the catalyst can further improve the conversion rate of the raw material and the selectivity of the target product when the catalyst is used to prepare hexamethylenediamine from hexamethyleneimine amination, and reduce the generation of by-products.

[0028] Other features and advantages of the present disclosure will be described in detail in the following specific implementation manner. DETAILED DESCRIPTION

[0029] The specific implementation manner of the present disclosure is described in detail below. It should be understood that the specific implementation manner described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0030] The first aspect of the present disclosure provides a catalyst for synthesizing hexamethylenediamine from hexamethyleneimine, the catalyst comprising 5-98 wt% of a titanium-containing carrier, 2-30 wt% of vanadium oxide, 0-30 wt% of metal M oxide and / or 0-10 wt% of inorganic oxide, based on dry basis and the total weight of the catalyst; wherein the titanium-containing carrier comprises titanium dioxide and a titanium-containing molecular sieve; the metal M is selected from one or more of the group consisting of the elements of group VB, the elements of group VIB, the elements of group VIII and the lanthanum elements; and the inorganic oxide is selected from one or both of Al2O3 and SiO2.

[0031] The catalyst provided by the present disclosure has high catalytic activity for the ammoniation reaction of hexamethyleneimine raw material, and can obtain high conversion rate of hexamethyleneimine raw material and selectivity of hexamethylenediamine. Moreover, the catalyst has high stability in the ammoniation reaction and can still have high catalytic activity under long-time reaction conditions. The inorganic oxide added in the catalyst can improve the strength of the catalyst, thereby improving the service life of the catalyst. The metal M oxide added in the catalyst can further improve the conversion rate of raw material and the selectivity of target product when the catalyst is used for preparing hexamethylenediamine from hexamethyleneimine, and reduce the generation of by-products.

[0032] According to the present disclosure, the hexamethyleneimine raw material can come from caprolactam hydrogenation liquid, which is obtained by hydrogenation of caprolactam by a method known in the art and mainly contains hexamethyleneimine. The content of hexamethyleneimine in the caprolactam hydrogenation liquid is more than 10 wt%, and the rest can be water.

[0033] In a preferred embodiment, the catalyst comprises 20-95 wt% of a titanium-containing carrier, 3-20 wt% of vanadium oxide, 0.5-10 wt% of metal M oxide and / or 0.2-6 wt% of inorganic oxide, based on dry basis and the total weight of the catalyst. When the content of each component of the catalyst meets the range in the present embodiment, the conversion rate and the selectivity of target product when the catalyst is used for preparing hexamethylenediamine from hexamethyleneimine can be further improved.

[0034] In the present disclosure, the content of each component in the catalyst is determined by an X-ray fluorescence spectrometer. The content of the titanium-containing carrier in the catalyst of the present disclosure is calculated according to the total Ti element oxide obtained by XRF testing.

[0035] In an embodiment, the titanium-containing carrier comprises TiO2 and a titanium-containing molecular sieve; and the weight ratio of TiO2 to the titanium-containing molecular sieve in the titanium-containing carrier is 1:(0.01-10), preferably 1:(0.001-5), based on dry basis. In the present disclosure, the weight ratio of TiO2 to the titanium-containing molecular sieve is calculated according to the mass ratio of the two raw materials added in the preparation process.

[0036] According to the present disclosure, TiO2 is well known to those skilled in the art, and when applied to a support of a catalytic material, rutile and anatase titanium dioxide can be used, preferably rutile. Titanium-containing molecular sieves are well known to those skilled in the art, and preferably include titanium silicalite molecular sieves; the titanium silicalite molecular sieves are selected from one or more of HTS, TS-1, TS-2 and TS-48 molecular sieves.

[0037] In one embodiment, the metal M is selected from one or more of tungsten, molybdenum, chromium, zinc, manganese, lanthanum and iron; preferably from one or more of tungsten, molybdenum and chromium, and further preferably from one or both of molybdenum and tungsten.

[0038] In one embodiment, the BET specific surface area of the catalyst is 10-200 m 2 / g, preferably 20-150 m 2 / g; the total pore volume is 0.02-0.3 mL / g, preferably 0.05-0.2 mL / g; and the micropore volume is 0.01-0.1 mL / g, preferably 0.03-0.1 mL / g.

[0039] In one embodiment, the catalyst is a granular shaped catalyst, and the shape of the catalyst is selected from one or more of a sphere, a rod, a cylinder, a ring, a trilobal shape, a quadrilobal shape, a honeycomb shape and a butterfly shape. Preferably, the catalyst is in the shape of a rod or a small ball with a diameter of 0.5-5.0 mm.

[0040] The catalyst in the present disclosure can be used in various reactors, such as a fixed bed reactor, a moving bed reactor or a fluidized bed reactor.

[0041] The second aspect of the present disclosure provides a method for preparing a catalyst for synthesizing hexamethylene diamine from hexamethylene imine, comprising the following steps:

[0042] S1, contacting a vanadium source, water and an acid to perform an oxidation reaction; adding a metal M source and a titanium-containing support to the oxidation reaction product to obtain a mixture; and performing a first drying treatment on the mixture to obtain an intermediate solid product;

[0043] S2, sequentially performing a shaping treatment, a second drying treatment and a calcination treatment on the intermediate solid product.

[0044] The present disclosure first performs an oxidation reaction on a vanadium source with an acid to obtain an oxidation product (for example, an oxidation reaction on a vanadium source with oxalic acid to obtain vanadyl oxalate), and then mixes the oxidation product with a metal M source and a titanium-containing support, and removes water by drying, so that the vanadyl oxalate and the metal M source are loaded on the titanium-containing support to obtain an intermediate solid product.

[0045] In one embodiment, in step S1, the weight ratio of water: vanadium source: acid: metal M source: titanium-containing carrier is (0.5-2.0):(0.05-0.2):(0.05-0.5):(0-0.5):1. In one preferred embodiment, the weight ratio of water: vanadium source: acid: metal M source: titanium-containing carrier is (0.8-1.6):(0.05-0.15):(0.1-0.3):(0.01-0.3):1. The catalyst prepared using the preferred raw material mass ratio provided in the present disclosure has higher reaction activity, achieving higher raw material conversion and target product selectivity. The titanium-containing carrier is based on the total weight of TiO2 added and the titanium-containing molecular sieve.

[0046] In one embodiment, in step S1, the vanadium source is selected from one or more of ammonium metavanadate, sodium metavanadate and di vanadium pentoxide;

[0047] The acid is selected from one or more of oxalic acid, citric acid and nitric acid;

[0048] The metal M source is selected from one or more of nitrate, phosphate and chloride salts of the metal M element; preferably one or more of ammonium molybdate tetrahydrate, sodium tungstate, chromium nitrate and lanthanum nitrate.

[0049] In one specific embodiment, step S1 comprises:

[0050] The vanadium source is dissolved in water, and then the acid is added to the vanadium source solution to perform the oxidation reaction, obtaining an oxidation reaction product;

[0051] The metal M source is added to the oxidation reaction product to perform a first mixing, obtaining a first mixture. Optionally, the temperature of the first mixing is 50-120°C, and the time is 60-500 min;

[0052] The titanium-containing carrier is added to the first mixture to perform a second mixing, obtaining a second mixture. Optionally, the temperature of the second mixing is 30-100°C, and the time is 60-500 min;

[0053] The second mixture is subjected to the first drying treatment, and the obtained product is ground to obtain the intermediate solid product. Optionally, the temperature of the first drying treatment is 70-160°C. Optionally, the grinding can be performed to a maximum particle size of 30 μm or less. The particle size is determined using a laser particle size analyzer.

[0054] According to the present disclosure, in step S2, the shaping treatment uses one of an extrusion molding process and a rolling ball molding process.

[0055] In one embodiment, when extrusion molding is used, step S2 further comprises: mixing the intermediate solid product with a pore-expanding agent and an auxiliary agent, and then sequentially performing the molding treatment, the second drying treatment and the calcination treatment.

[0056] In one preferred embodiment, the pore-expanding agent is added in an amount of 0.5-10% by weight, preferably 1-5% by weight, based on the dry basis and the added weight of the titanium-containing carrier; and the auxiliary agent is added in an amount of 0.5-4% by weight, preferably 0.5-2% by weight, based on the dry basis and the added weight of the titanium-containing carrier.

[0057] In one specific embodiment, the pore-expanding agent is selected from one or more of sesbania powder, paraffin, stearic acid, glycerol, starch, polyethylene glycol, polyvinyl alcohol, polyethylene oxide, polyacrylamide, cellulose methyl ether, cellulose, polyhydric alcohol and graphite.

[0058] The auxiliary agent is selected from one or more of oxalic acid, tartaric acid, citric acid, nitric acid, hydrochloric acid, acetic acid, formic acid, ammonia, sodium hydroxide and potassium hydroxide. The addition of the pore-expanding agent and the auxiliary agent in step S2 of the present disclosure facilitates the basic molding treatment of the catalyst and increases the pores of the catalyst.

[0059] In another embodiment, when roll ball molding is used, step S2 further comprises: mixing the intermediate solid product with an inorganic oxide source, and then sequentially performing the molding treatment, the second drying treatment and the calcination treatment.

[0060] According to the present disclosure, the inorganic oxide acts as a binder to bond the titanium-containing carrier and the vanadium oxide and metal M oxide powder particles together during extrusion, thereby improving the strength and service life of the catalyst.

[0061] In one preferred embodiment, the inorganic oxide source is added in an amount of 0.1-5% by weight, preferably 0.1-2.0% by weight, based on the dry basis and the added weight of the titanium-containing carrier. The present disclosure adds an appropriate amount of the inorganic oxide source to avoid the phenomenon that an insufficient amount of the inorganic oxide source makes the catalyst difficult to be molded, and even if the catalyst is forced to be molded, it will break when leaving the molding machine; and to avoid the phenomenon that an excessive amount of the inorganic oxide source makes the spherical product soft and sticky.

[0062] According to the present disclosure, the inorganic oxide in the catalyst can be added in the form of an inorganic oxide or in the form of a precursor thereof, and the inorganic oxide is selected from one or both of Al2O3 and SiO2.

[0063] The inorganic oxide precursor is selected from one or more of an aluminum sol, a silicon sol and water glass.

[0064] In the present disclosure, the inorganic oxide as the inert substance can resist the corrosion of strong acid and strong base, so that the shaped particles are not crushed during the alkaline extraction process.

[0065] In further embodiments, if the silica sol is used as the binder, it can be acidic or alkaline, and can be commercially available or prepared according to any prior art. Other inorganic oxide precursors known to those skilled in the art for binding can also be added during the preparation of the composite catalyst.

[0066] In one embodiment, in step S2, the conditions of the second drying treatment include: a drying temperature of 80-200°C, preferably 100-150°C; and a drying time of 1-10h, preferably 2-4h.

[0067] The conditions of the calcination include: a calcination temperature of 200-900°C, preferably 500-800°C; and a calcination time of 0.5-10h, preferably 2-4h. According to the present disclosure, the drying treatment and calcination treatment after the shaping treatment can improve the strength of the catalyst.

[0068] The third aspect of the present disclosure provides a catalyst prepared according to the method of the second aspect.

[0069] The fourth aspect of the present disclosure provides a method for the amination of hexamethyleneimine to prepare 6-aminocapronitrile, comprising: contacting a hexamethyleneimine raw material, an amination catalyst, and ammonia gas in a reactor to perform an amination reaction; the amination catalyst comprising the catalyst of the first aspect or the third aspect of the present disclosure.

[0070] In one embodiment, the conditions of the amination reaction include: a reaction temperature of 200-500°C, a weight ratio of ammonia gas to hexamethyleneimine raw material of (0.1-20):1, an ammonia gas partial pressure of 0.1-8.0MPa, and a hexamethyleneimine raw material weight hourly space velocity of 0.2-100h -1 ; preferably, a reaction temperature of 220-350°C, a weight ratio of ammonia gas to hexamethyleneimine raw material of (0.5-10):1, an ammonia gas partial pressure of 0.5-3MPa, and a hexamethyleneimine raw material weight hourly space velocity of 0.5-5h -1 . According to the present disclosure, the reactor is a fixed bed reactor; the fixed bed reactor comprises a packing layer, and the packing layer comprises the amination catalyst.

[0071] According to the present disclosure, in the raw material gas mixture, an inert gas such as nitrogen can be used for dilution. The reaction is usually carried out at normal pressure, and the reactant gas is discharged from the bottom of the fixed bed reactor and enters the absorption tower through a cooler to obtain a solid reaction product.

[0072] According to the present disclosure, the hexamethyleneimine raw material comprises a caprolactam hydrogenation liquid; the caprolactam hydrogenation liquid comprises 10-80 wt% of hexamethyleneimine and 20-90 wt% of water. The caprolactam hydrogenation liquid can be prepared according to a known caprolactam hydrogenation reaction.

[0073] With the catalyst and the amination process provided by the present disclosure, the reaction temperature is low, the molar ratio of the hexamethyleneimine raw material to ammonia is small, the raw material conversion rate is high, and the selectivity of the target product is high.

[0074] The specific embodiments of the present disclosure are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure.

[0075] In the following examples, unless otherwise specified, the reagents used are commercially available reagents.

[0076] In the following examples and comparative examples, unless otherwise specified, the pressure is gauge pressure.

[0077] The crushing strength of the catalyst is measured according to the RIPP-25-90 method in Petroleum Chemical Industry Analysis Method (Yang Cuiding et al., Science Press, 1990) on a particle strength tester QCY-602.

[0078] In the following examples, the content of each component in the catalyst is measured by an X-ray fluorescence spectrometer.

[0079] The BET specific surface area, total pore volume and micropore volume of the catalyst are measured by a Micromeritics ASAP-2020 automatic adsorption instrument, the specific surface area is calculated using the two-parameter BET equation, the BJH method is used to calculate the pore distribution, and the t method is used to calculate the micropore specific surface area and pore volume.

[0080] The particle size is measured by a Mastersizer 2000 laser particle size analyzer.

[0081] The preparation examples are used to provide a catalyst for synthesizing hexanediamine from hexamethyleneimine.

[0082] Preparation Example 1

[0083] Preparation of vanadyl oxalate: 60 g of ammonium metavanadate was dissolved in 700 g of water and heated in a water bath, 130 g of oxalic acid crystals were slowly added under stirring, and the oxidation reaction was carried out at 80°C for 120 min until the color of the slurry changed from yellow to purple, and the heating on the water bath was continued for 30 min to prepare a vanadyl oxalate solution.

[0084] The above solution was continuously stirred at 70°C, and 500 g of TiO2(DuPont R900) and 50 g of titanium silicalite (Hunan Jianchang product, HTS-3 molecular sieve) were added to the above solution under continuous stirring, and the stirring was continued for 4 h of aging. The resulting product was dried in an oven at 110°C for 4 h to remove water. The dried material was added to a grinder and ground for 30 min to obtain an intermediate solid product (maximum particle size less than 30 microns).

[0085] In the above step, the weight ratio of water: vanadium source: acid: metal M source: titanium-containing carrier was 1.273:0.109:0.236:0:1.

[0086] To the intermediate solid product, 15 g of sesbania powder (purchased from Lankao Plant Gum Factory) and 20 g of 20 wt% nitric acid aqueous solution (4 g of nitric acid) were continuously added and mixed thoroughly, wherein the amount of sesbania powder added was 2.7 wt% based on the total weight of the titanium-containing carrier on a dry basis, and the amount of nitric acid added was 0.73 wt%; then the catalyst was extruded into a strip-shaped catalyst with a diameter of 2.5 mm by using an extruder, and then dried at 120°C for 4 h, and then calcined at 750°C for 8 h to obtain a strip-shaped catalyst, which is denoted as catalyst A1.

[0087] After the catalyst A1 was dried, the strength was measured by using a strength tester and the strength was 30 N / cm.

[0088] The composition of the catalyst A1 was 91.8 wt% TiO2, 7.8 wt% V2O5, and 0.4 wt% SiO2.

[0089] Preparation Example 2

[0090] Preparation of vanadyl oxalate: 50 g of ammonium metavanadate was dissolved in 600 g of water, and heated in a water bath, and 110 g of oxalic acid crystals were slowly added under stirring, and the oxidation reaction was carried out at 80°C for 120 min until the color of the slurry changed from yellow to purple, to obtain a vanadyl oxalate solution.

[0091] Then 30 g of ammonium molybdate tetrahydrate was added, and the heating was continued on the water bath for 30 min to obtain an aqueous solution containing vanadyl oxalate and ammonium molybdate.

[0092] The above solution was continuously stirred at 70°C, and 500 g of TiO2(DuPont R900) and 50 g of titanium silicalite (Hunan Jianchang product, HTS-3 molecular sieve) were added to the above solution under continuous stirring, and the stirring was continued for 4 h of aging. The resulting product was dried in an oven at 110°C for 4 h to remove water. The dried material was added to a grinder and ground for 30 min to obtain an intermediate solid product (maximum particle size less than 30 microns).

[0093] The weight ratio of water:vanadium source:acid:metal M source:titanium-containing support in the above step is 1.091:0.091:0.2:0.055:1.

[0094] Then 20 g of aluminum sol (Hunan Jianchang product) was added to the intermediate solid product and mixed well, wherein the amount of aluminum sol added was 3.6% by weight based on the dry basis and based on the added weight of the titanium-containing support; then the obtained catalyst was rolled into small balls in a ball-rolling machine, and small balls with a diameter of 2.0-3.0 mm were screened out, and then the obtained small balls were dried at 120°C for 4 h, and then calcined at 750°C for 8 h to obtain a small ball catalyst, which is recorded as catalyst A2.

[0095] The strength of the dried catalyst A2 was measured by a strength tester and was greater than 60 N / ball.

[0096] The composition of catalyst A2 was 88.8% by weight of TiO2, 6.3% by weight of V2O5, 4.0% by weight of MoO3, 0.4% by weight of SiO2, and 0.5% by weight of Al2O3.

[0097] Preparation Example 3

[0098] Preparation of vanadyl oxalate: 50 g of ammonium metavanadate was dissolved in 600 g of water, and heated in a water bath, and 110 g of oxalic acid crystals were slowly added under stirring, and the oxidation reaction was carried out at 80°C for 120 min until the color of the slurry changed from yellow to purple, to obtain a vanadyl oxalate solution.

[0099] Then 12 g of sodium tungstate was continuously added and heated on a water bath for 30 min to obtain an aqueous solution containing vanadyl oxalate and sodium tungstate.

[0100] The above solution was continuously stirred at 70°C, and 500 g of TiO2 (DuPont R900) and 50 g of titanium silicalite (Hunan Jianchang product, HTS-3 molecular sieve) were added to the above solution under continuous stirring, and the stirring was continued for 4 h. The obtained product was dried in an oven at 110°C for 4 h to remove water. The dried material was added to a grinding machine and ground for 30 min to obtain an intermediate solid product (the maximum particle size was less than 40 microns).

[0101] The weight ratio of water:vanadium source:acid:metal M source:titanium-containing support in the above step is 1.091:0.091:0.2:0.022:1.

[0102] To the intermediate solid product, 15 g of sesbania powder (purchased from LanKao Plant Gum Factory) and 20 g of 2.0 wt% nitric acid aqueous solution (0.4 g of nitric acid) were continuously added and mixed thoroughly, wherein the amount of sesbania powder added was 2.7 wt% based on dry basis and the total weight of the titanium-containing support, and the amount of nitric acid added was 0.073 wt% based on the total weight of the titanium-containing support; then the catalyst was extruded into a strip-shaped catalyst with a diameter of 2.5 mm by using an extruder, and then dried at 120 °C for 4 h, and then calcined at 600 °C for 8 h to obtain a strip-shaped catalyst, which is denoted as catalyst A3.

[0103] After the catalyst A3 was dried, the strength was measured by using a strength tester, and the strength was 38 N / cm.

[0104] The catalyst A3 had a composition of 91.5 wt% of Ti02, 6.5 wt% of V205, 1.6 wt% of W03, and 0.4 wt% of Si02.

[0105] Preparation of Comparative Example 1

[0106] The same method as that of Preparation Example 3 was used, except that the following differences were made in Preparation Example 3:

[0107] 10 g of ammonium metavanadate, 20 g of oxalic acid crystals, and 10 g of sodium tungstate were used; and the rest of the process was the same as that of Preparation Example 3. The obtained product is denoted as D-1. The weight ratio of water: vanadium source: acid: metal M source: titanium-containing support was 1.091:0.018:0.036:0.018:1.

[0108] After the catalyst D-1 was dried, the strength was measured by using a strength tester, and the strength was 23 N / cm.

[0109] The catalyst D-1 had a composition of 96.8 wt% of Ti02, 1.4 wt% of V205, 1.4 wt% of W03, and 0.4 wt% of Si02.

[0110] Preparation of Example 4

[0111] Preparation of vanadyl oxalate: 50 g of ammonium metavanadate was dissolved in 600 g of water, and heated in a water bath, and 110 g of oxalic acid crystals were slowly added under stirring, and the oxidation reaction was carried out at 80 °C for 120 min, until the color of the slurry changed from yellow to purple, to obtain a vanadyl oxalate solution.

[0112] Then, 21 g of chromium nitrate was continuously added, and heating was continued on the water bath for 30 min, to obtain an aqueous solution containing vanadyl oxalate and chromium nitrate.

[0113] The above solution was continuously stirred at 70°C, and 500 g of TiO2(DuPont R900) and 50 g of titanium silicalite (Hunan Jianchang product, HTS-3 molecular sieve) were added to the above solution under continuous stirring, and the stirring was continued for aging for 4 h. The resulting product was dried in an oven at 110°C for 4 h to remove water. The dried material was added to a grinder and ground for 30 min to obtain an intermediate solid product (the maximum particle size was less than 40 microns).

[0114] In the above step, the weight ratio of water: vanadium source: acid: metal M source: titanium-containing carrier was 1.091:0.091:0.2:0.038:1.

[0115] To the intermediate solid product, 15 g of sesbania powder (purchased from Lankao Plant Gum Factory) and 20 g of 20 wt% nitric acid aqueous solution (4 g of nitric acid) were continuously added and mixed thoroughly, wherein the amount of sesbania powder added was 2.7 wt% based on the total weight of the titanium-containing carrier on a dry basis, and the amount of nitric acid added was 0.73 wt%; then the catalyst was extruded into a strip-shaped catalyst with a diameter of 2.5 mm by using an extruder, and then dried at 120°C for 4 h, and then calcined at 750°C for 8 h to obtain a strip-shaped catalyst, which was recorded as catalyst A4.

[0116] After the catalyst A4 was dried, the strength was measured by using a strength tester, and the strength was 35 N / cm.

[0117] The composition of the catalyst A4 was 91.8 wt% of TiO2, 6.5 wt% of V2O5, 1.3 wt% of Cr2O3, and 0.4 wt% of SiO2.

[0118] Preparation Example 5

[0119] Preparation of vanadyl oxalate: 50 g of ammonium metavanadate was dissolved in 600 g of water, and heated in a water bath, and 110 g of oxalic acid crystals were slowly added under stirring, and the oxidation reaction was carried out at 80°C for 120 min until the color of the slurry changed from yellow to purple, to obtain a vanadyl oxalate solution.

[0120] Then 10 g of lanthanum nitrate was added, and the heating was continued on the water bath for 30 min to obtain an aqueous solution containing vanadyl oxalate and lanthanum nitrate.

[0121] The above solution was continuously stirred at 70°C, and 500 g of TiO2(DuPont R900) and 50 g of titanium silicalite (Hunan Jianchang product, HTS-3 molecular sieve) were added to the above solution under continuous stirring, and the stirring was continued for aging for 4 h. The resulting product was dried in an oven at 110°C for 4 h to remove water. The dried material was added to a grinder and ground for 30 min to obtain an intermediate solid product (the maximum particle size was less than 40 microns).

[0122] In the above procedure, the weight ratio of water:vanadium source:acid:metal M source:titanium-containing support was 1.091 :0.091 :0.2:0.018:1.

[0123] To the intermediate solid product, 15 g of sesbania powder (purchased from LanKao Plant Gum Factory) and 20 g of 20 wt% nitric acid aqueous solution (4 g of nitric acid) were added and mixed thoroughly, wherein the amount of sesbania powder added was 2.7 wt% and the amount of nitric acid added was 0.73 wt% based on the total weight of the titanium-containing support on a dry basis; the catalyst was then extruded into a 2.5 mm diameter strip shape using an extruder, and then dried at 120°C for 4 h, and then calcined at 750°C for 8 h to obtain a strip-shaped catalyst, which was labeled as catalyst A5.

[0124] After drying, the strength of catalyst A5 was measured to be 36 N / cm using a strength tester.

[0125] Catalyst A5 had a composition of 92.3 wt% TiO2, 6.5 wt% V2O5, 0.8 wt% La2O3, and 0.4 wt% SiO2.

[0126] Preparation Example 6

[0127] Preparation of vanadyl oxalate: 80 g of ammonium metavanadate was dissolved in 600 g of water and heated in a water bath, and 140 g of oxalic acid crystals were slowly added while stirring, and the oxidation reaction was carried out at 80°C for 120 min until the color of the slurry changed from yellow to purple, to obtain a vanadyl oxalate solution.

[0128] Then 40 g of ammonium molybdate was added and heated on a water bath for 30 min to obtain an aqueous solution containing vanadyl oxalate and ammonium molybdate.

[0129] The above solution was continuously stirred at 70°C, and 500 g of TiO2(DuPont R900) and 50 g of titanium silicalite (Hunan Jianchang Product HTS-3 molecular sieve) were added to the above solution while continuously stirring, and the stirring was continued for 4 h. The resulting product was dried in an oven at 110°C for 4 h to remove water. The dried material was ground in a grinder for 30 min to obtain an intermediate solid product (with a maximum particle size of less than 40 microns).

[0130] In the above procedure, the weight ratio of water:vanadium source:acid:metal M source:titanium-containing support was 1.091 :0.145 :0.255 :0.073 :1.

[0131] Then 20 g of silica sol (purchased from Aldrich Company, trademark LUDOX AS-40) was added to the intermediate solid product and mixed well, wherein the silica sol was added in an amount of 3.6% by weight based on the dry basis and based on the added weight of the titanium-containing carrier; then the obtained catalyst was turned into small balls in a balling machine, and small balls with a diameter of 2.0-3.0 mm were screened out from the small balls, and then the obtained small balls were dried at 120°C for 4 h, and then calcined at 550°C for 8 h to obtain a small ball catalyst, which is denoted as catalyst A6.

[0132] After the catalyst A6 was dried, the strength of the catalyst was measured by a strength tester, and the strength was greater than 80 N / particle.

[0133] The catalyst A6 had a composition of 83.9% by weight of TiO2, 9.5% by weight of V2O5, 5.0% by weight of MoO3, and 1.6% by weight of SiO2.

[0134] Example 7

[0135] The same preparation method as in Example 6 was used, except that the calcination temperature was 450°C and the calcination time was 10 h, and the rest of the process was the same as in Example 6, to obtain a small ball catalyst, which is denoted as A7.

[0136] After the catalyst A7 was dried, the strength of the catalyst was measured by a strength tester, and the strength was greater than 25 N / particle.

[0137] The catalyst A7 had a composition of 83.7% by weight of TiO2, 9.7% by weight of V2O5, 5.0% by weight of MoO3, and 1.6% by weight of SiO2.

[0138] The structural and performance data of the catalyst products obtained in the above examples and comparative examples are listed in Table 1 below.

[0139] Table 1

[0140]

[0141] The following reaction examples are used to illustrate the reaction effect of the catalyst provided in the present application on the synthesis of hexamethylenediamine by hydrogenation liquid ammonia of caprolactam in a fixed bed reactor.

[0142] In the following reaction examples, the reaction devices used are devices of conventional structures in the art.

[0143] Reaction Example

[0144] 10 g of the catalyst obtained in the preparation examples or the preparation comparative examples was loaded into a fixed bed reactor The middle part of a stainless steel reactor with a jacket, both ends filled with inert quartz sand. 10 g / h (0.088 mol / h) of hexamethylene imine was mixed with 7.5 g / h (0.44 mol / h) of hot ammonia, N2 (the molar ratio of HMI, ammonia and nitrogen was 1:5:5) at 100 ℃. The hexamethylene imine was from caprolactam hydrogenation liquid (hexamethylene imine content was 20 wt%, the rest was water), the flow rate of caprolactam hydrogenation liquid was 50 g / h, the space velocity of caprolactam hydrogenation liquid was 5.0 h -1 , the reaction temperature was 300 ℃, and the reaction pressure was 1 MPa. The ammoniated reactant was deaminated, dehydrated, and then subjected to vacuum distillation to obtain hexamethylene diamine with a purity of 99.0 wt%. The conversion of hexamethylene imine and the selectivity of hexamethylene diamine were measured and calculated at 20 h and 200 h of reaction, respectively. The specific data are shown in Table 2.

[0145] The preparation method of the caprolactam hydrogenation liquid includes: continuously feeding the molten caprolactam liquid into a suspension bed reactor containing a solvent, the reaction temperature is 240 ℃, the pressure is 5.0 MPa, the solvent is dodecane, the concentration of caprolactam is 10 wt%, and excess hydrogen is introduced at the same time; continuously extracting the gas phase low boiling point substance from the reactor; the incondensable gas is sent back to the reactor together with the supplementary hydrogen, and the condensate in the distillation column is the caprolactam hydrogenation liquid.

[0146]

[0147]

[0148] Table 2

[0149]

[0150] According to Table 2 above, by comparing D-1 with A3, it can be seen that the catalyst A3 prepared by the method provided by the present disclosure can obtain higher conversion of hexamethylene imine and selectivity of hexamethylene diamine in the catalytic reaction of hexamethylene imine; and the conversion of hexamethylene imine and the selectivity of hexamethylene diamine change less at 200 h of reaction and 20 h of reaction, and the stability is higher.

[0151] Further, comparing A1 with A2-A6, it can be seen that A2-A6 satisfy the condition of "weight ratio of water: vanadium source: acid: metal M source: titanium-containing carrier is (0.8-1.6):(0.05-0.15):(0.1-0.3):(0.01-0.3):1" in the preparation process, and the catalyst composition satisfies "the catalyst comprises 20-95 wt% of the titanium-containing carrier, 3-20 wt% of vanadium oxide, 0.5-10 wt% of metal M oxide and / or 0.2-6 wt% of inorganic oxide", and A2-A6 can obtain higher hexamethyleneimine conversion rate, hexamethylene diamine selectivity and better stability in the hexamethyleneimine catalytic reaction.

[0152] Comparing A7 with A3, it can be seen that A3 satisfies the condition of "calcination temperature is 500-800℃; time after calcination is 2-8h" in the preparation process, and A3 can obtain higher hexamethyleneimine conversion rate, hexamethylene diamine selectivity and better stability in the hexamethyleneimine catalytic reaction.

[0153] The above describes the preferred embodiments of the present disclosure in detail, but the present disclosure is not limited to the specific details in the above-described embodiments, and various simple modifications can be made to the technical solutions of the present disclosure within the technical concept of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

[0154] In addition, it should be noted that each specific technical feature described in the above-described specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combination manners.

[0155] In addition, various different embodiments of the present disclosure can also be combined in any manner, as long as it does not deviate from the idea of the present disclosure, and it should also be considered as the disclosed content of the present disclosure.

Claims

1. A catalyst for the synthesis of hexamethylenediamine from hexamethyleneimine, characterized in that, The catalyst comprises 20-95 wt% of a titanium-containing carrier, 3-20 wt% of vanadium oxide, 0.5-10 wt% of metal M oxide and / or 0.2-6 wt% of inorganic oxide, based on the total weight of the catalyst; wherein the titanium-containing carrier comprises titanium dioxide and a titanium-containing molecular sieve; the metal M is selected from one or more of the group consisting of a VIB element, a VIII element and a lanthanum element; and the inorganic oxide is selected from one or both of Al2O3 and SiO2.

2. The catalyst according to claim 1, characterized in that, The titanium-containing molecular sieve comprises a titanium silicalite molecular sieve; and the titanium silicalite molecular sieve is selected from one or more of HTS, TS-1 molecular sieve, TS-2 molecular sieve and TS-48 molecular sieve.

3. The catalyst of claim 1, wherein The metal M is selected from one or more of tungsten, molybdenum, chromium, lanthanum and iron.

4. The catalyst of claim 1, wherein The BET specific surface area of the catalyst is 10-200 m 2 / g, the total pore volume is 0.02-0.3 mL / g, and the micropore volume is 0.01-0.1 mL / g.

5. The catalyst of claim 1, wherein The catalyst has a shape selected from one or more of a spherical shape, a strip shape, a cylindrical shape, a ring shape, a trilobal shape, a quadrilobal shape, a honeycomb shape and a butterfly shape.

6. A process for the preparation of a catalyst for the synthesis of hexamethylenediamine from hexamethyleneimine, characterized in that, The method comprises the following steps: S1, contacting a vanadium source, water and an acid to perform an oxidation reaction; adding a titanium-containing carrier and an optional metal M source to the oxidation reaction product to obtain a mixture; and performing a first drying treatment on the mixture to obtain an intermediate solid product; S2, sequentially performing a molding treatment, a second drying treatment and a calcination treatment on the intermediate solid product; The titanium-containing carrier comprises titanium dioxide and a titanium-containing molecular sieve; and the metal M is selected from one or more of the group consisting of a VIB element, a VIII element and a lanthanum element.

7. The method of claim 6, wherein, In step S1, the weight ratio of water:vanadium source:acid:metal M source:titanium-containing carrier is (0.5-2.0):(0.05-0.2):(0.05-0.5):(0-0.5):

1.

8. The method of claim 7, wherein, The weight ratio of water:vanadium source:acid:metal M source:titanium-containing carrier is (0.8-1.6):(0.05-0.15):(0.1-0.3):(0.01-0.3):

1.

9. The method of claim 6, wherein, In step S1, the vanadium source is selected from one or more of ammonium metavanadate, sodium metavanadate and divanadium pentoxide; The acid is selected from one or more of oxalic acid, citric acid and nitric acid; The metal M source is selected from one or more of a nitrate salt, a phosphate salt and a chloride salt of the metal M element.

10. The method of claim 9, wherein, The metal M source is selected from one or more of ammonium molybdate tetrahydrate, sodium tungstate, chromium nitrate and lanthanum nitrate.

11. The method of claim 6, wherein, Step S1 comprises: dissolving the vanadium source in water, and then adding the acid to the vanadium source solution to perform the oxidation reaction to obtain an oxidation reaction product; adding the metal M source to the oxidation reaction product to perform a first mixing to obtain a first mixture; adding the titanium-containing carrier to the first mixture to perform a second mixing to obtain a second mixture; performing the first drying treatment on the second mixture, and then performing a grinding to obtain the intermediate solid product.

12. The method of claim 11, wherein, The first mixing is performed at a mixing temperature of 50-100°C for a mixing time of 60-300 min.

13. The method of claim 11, wherein, The second mixing is performed at a mixing temperature of 30-80°C for a mixing time of 30-300 min.

14. The method of claim 11, wherein, The first drying treatment is performed at a temperature of 80-150°C.

15. The method of claim 6, wherein, The forming process in step S2 is an extrusion forming process or a rolling ball forming process.

16. The method of claim 15, wherein, The extrusion forming process The method comprises the following steps: mixing the intermediate solid product with a pore-expanding agent and an extrusion aid, and then sequentially performing the forming process, a second drying process and a calcination process.

17. The method of claim 15, wherein, The rolling ball forming process The method comprises the following steps: mixing the intermediate solid product with an inorganic oxide source, and then sequentially performing the forming process, a second drying process and a calcination process.

18. The method of claim 16, wherein, The conditions of the extrusion forming process include: the pore-expanding agent is added in an amount of 0.5-10% by weight based on the dry basis and the added weight of the titanium-containing carrier; and the extrusion aid is added in an amount of 0.5-4% by weight based on the dry basis and the added weight of the titanium-containing carrier.

19. The method of claim 18, wherein, The conditions of the extrusion forming process include: the pore-expanding agent is added in an amount of 0.5-10% by weight based on the dry basis and the added weight of the titanium-containing carrier; and the extrusion aid is added in an amount of 0.5-4% by weight based on the dry basis and the added weight of the titanium-containing carrier.

20. The method of claim 16, wherein, The pore-expanding agent is selected from one or more of sesbania gum, paraffin wax, stearic acid, glycerol, starch, polyvinyl alcohol, polyethylene oxide, polyacrylamide, cellulose methyl ether, cellulose, polyhydric alcohol and graphite.

21. The method of claim 16, wherein, The extrusion aid is selected from one or more of an organic acid, an inorganic acid and an inorganic base.

22. The method of claim 21, wherein, The extrusion aid is selected from one or more of oxalic acid, tartaric acid, citric acid, nitric acid, hydrochloric acid, acetic acid, formic acid, aqueous ammonia, sodium hydroxide and potassium hydroxide.

23. The method of claim 17, wherein, The conditions of the rolling ball forming process include: the inorganic oxide source is added in an amount of 0.1-5% by weight based on the dry basis and the added weight of the titanium-containing carrier.

24. The method of claim 23, wherein, The conditions of the rolling ball forming process include: the inorganic oxide source is added in an amount of 0.1-5% by weight based on the dry basis and the added weight of the titanium-containing carrier.

25. The method of claim 17, wherein, The inorganic oxide source is added in the form of an inorganic oxide or an inorganic oxide precursor.

26. The method of claim 25, wherein, The inorganic oxide is selected from one or both of Al2O3 and SiO2.

27. The method of claim 25, wherein, The inorganic oxide precursor is selected from one or more of an aluminum sol, a silicon sol and water glass.

28. The method of claim 6, wherein, The conditions of the second drying process in step S2 include: a drying temperature of 80-200°C; and a drying time of 1-10h. The conditions of the calcination include: a calcination temperature of 200-900°C; and a post-calcination time of 0.5-10h.

29. The method of claim 28, wherein, The conditions of the second drying process include: a drying temperature of 100-150°C; and a drying time of 2-4h.

30. The method of claim 28, wherein, The conditions of the calcination include: a calcination temperature of 500-800°C; and a post-calcination time of 2-8h.

31. A catalyst prepared by the method of any one of claims 6-30.

32. A method of synthesizing hexamethylenediamine from hexamethyleneimine by amination, characterized in that, The method comprises: contacting a hexamethyleneimine raw material, an ammoniation catalyst and ammonia gas in a reactor to perform an ammoniation reaction; The ammoniation catalyst comprises the catalyst of any one of claims 1-5 and claim 31.

33. The method of claim 32, wherein, The conditions of the amination reaction include: reaction temperature of 200-500℃, weight ratio of ammonia to hexamethyleneimine raw material of (0.1-20):1, ammonia partial pressure of 0.1-8.0MPa, and weight hourly space velocity of hexamethyleneimine raw material of 0.2-100h -1 .

34. The method of claim 32, wherein, The reactor is a fixed bed reactor; the fixed bed reactor comprises a packing layer, and the packing layer comprises the ammoniation catalyst.

35. The method of claim 32, wherein, The hexamethyleneimine raw material comprises a caprolactam hydrogenation liquid.

36. The method of claim 35, wherein, The caprolactam hydrogenation liquid comprises 10-80% by weight of hexamethyleneimine and 20-90% by weight of water.

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