Process for the catalytic aminolysis of bis(hexamethylene)triamine

Abstract

This invention relates to the field of organic catalysis and discloses a method for catalyzing the ammonolysis of bis(hexamethylene)triamine. The catalyst comprises a support and a main active component and an auxiliary agent supported on the support. The main active component is Ni, the auxiliary agent includes La, and the support comprises alumina, with the alumina content being 50-80 wt% of the total weight of the support. Using the method of this invention, high conversion and selectivity can be obtained when catalyzing the ammonolysis of bis(hexamethylene)triamine, and the catalyst also exhibits high stability.

Description

Technical Field

[0001] This invention relates to the field of organic catalysis, and more specifically to a method for catalyzing the ammonolysis of bis(hexamethylene)triamine. Background Technology

[0002] Hexamethylenediamine, with the molecular formula C6H 16 N2, possessing a hexane carbon chain backbone and amino functional groups at both ends, is a colorless solid with a strong ammonia odor, similar to piperidine. It is mainly used in the production of polyamides, such as nylon 66 and nylon 610; it is also used in the synthesis of diisocyanate (HDI); and can be used as a curing agent and organic crosslinking agent in urea-formaldehyde resins and epoxy resins. Hexamethylenediamine is mostly prepared by hydrogenating adiponitrile. The synthesis technology and industrial production of adiponitrile and hexamethylenediamine have always been of great concern both domestically and internationally, representing a bottleneck technology. Due to foreign technological blockades, domestic production capacity of adiponitrile and hexamethylenediamine is low, and the market is heavily reliant on imports.

[0003] CN1270543A uses a complex catalyst of zero-valent nickel and at least one phosphonic acid ligand for the hydrocyanation of butadiene, producing a highly selective mononitrile. This catalytic system can be mixed with excess hydrogen cyanide, resulting in a higher catalyst cycle rate and longer lifespan. CN106397476A uses mixed phenols to prepare monodentate phosphorus ligands in the hydrocyanation of butadiene. Compared with catalysts prepared from single phenols, this method reduces production costs, increases activity, and eliminates the need for Lewis acid promoters in isomerization reactions. Furthermore, it effectively inhibits catalyst poisoning and organophosphorus ligand degradation in secondary hydrocyanation reactions. CN112794948A developed a multiphase reaction for the hydrocyanation of butadiene using porous polymers. The porous polymers have a pore volume of 0.5-2.0 ml / g, a pore volume ratio of 2-6 nm pores to pore volumes greater than 20 nm of 2-8:1, and a phosphorus content of 1.7-3.9 mmol / g. A porous polymer-nickel catalyst was then prepared, which significantly increased water resistance, eliminated the need for dehydration of the raw materials, and exhibited high catalytic activity, high reaction selectivity, and high linearity in the hydrocyanation reaction. The catalyst is also easily recyclable.

[0004] The earliest proposed and implemented method for the electrolytic dimerization of acrylonitrile was by Monsanto in the United States. US3497429 developed an emulsion process for adiponitrile production, where the electrolyte contains 55% acrylonitrile, 28% isopropanol, and 1% quaternary ammonium salt. Isopropanol is added to prevent acrylonitrile and quaternary ammonium salt oxidation at the anode, maintain electrolyte pH stability, and act as a co-solvent. Additionally, a trace amount of polyvinyl alcohol is added to the catholyte as an emulsifier. US4789442, based on Monsanto's technology, developed an emulsion process for adiponitrile production. Acrylonitrile, with the aid of an emulsifier, emulsifies with the electrolyte in the catholyte, with the oil phase comprising 15-25%. The anolyte is a dilute sulfuric acid solution, and the electrolytic dimerization reaction takes place. CN111228941A studied the process for producing adiponitrile through acrylonitrile dimerization. This process uses a circulating carrier, and the material exiting the electrolytic reactor includes the circulating carrier, the product oil phase, and the gas phase, which are mostly separated using a three-phase separator.

[0005] CN108821997A reacts adipic acid with ammonia at 155-200℃ to produce ammonium adipate, which is then dehydrated under the catalysis of phosphoric acid or ammonium phosphate to produce adiponitrile. This avoids the formation of byproducts and coking of adipic acid at high temperatures, increases the yield by 3-5%, extends the operating cycle by 30-60 days, and increases the catalyst throughput.

[0006] Besides the hydrogenation of adiponitrile, other methods for preparing hexamethylenediamine include the amination and dehydration of caprolactam to prepare 6-aminohexanonitrile followed by hydrogenation, and the direct amination of hexanediol. US20160326092A1 provides a method for preparing hexamethylenediamine, in which 1,6-hexanediol is catalytically aminationed to obtain hexamethylenediamine. The fraction rich in cycloheximine obtained after separation of the amination product is recycled to the amination process. The amination feedstock contains 20–35% cycloheximine and 65–80% hexanediol, with cycloheximine used as a solvent. Aminohexanol and hexamethylenediamine have very similar vapor pressures; the mixture of aminohexanol and hexamethylenediamine obtained by distillation is recycled for amination to obtain pure hexamethylenediamine.

[0007] Cycloheximine (HMI) is also an important chemical intermediate and a highly technical organic fine chemical. However, due to the difficulty in selecting catalysts for its synthesis, only a few countries in the world are capable of producing it. US4035353 describes a method using impregnation, co-precipitation, or mixing of an aqueous solution containing molybdenum and rhenium compounds with a pre-precipitated cobalt salt to tightly bind several catalyst components together. This is followed by thorough drying at 80–120°C and reduction at 350–600°C for several hours in a reducing atmosphere to obtain cobalt-molybdenum, cobalt-rhenium, or cobalt-molybdenum-rhenium bimetallic or trimetallic catalysts. Using this catalyst, coupled with a self-developed continuous process, can significantly reduce byproducts and extend catalyst life. However, caprolactam polymerizes readily, has a low conversion rate, and currently exhibits short catalyst life and low selectivity.

[0008] However, the current processes for producing hexamethylenediamine and cycloheximine are generally plagued by harsh reaction conditions, poor reaction selectivity, low conversion rate, and poor stability, requiring further optimization of the processes. Summary of the Invention

[0009] The purpose of this invention is to overcome the aforementioned problems in the prior art and provide a method for catalytic ammonolysis of bis(hexamethylene)triamine. When using the method of this invention to catalyze ammonolysis of bis(hexamethylene)triamine, a high conversion rate can be obtained, and the prepared hexamethylenediamine and cycloheximine have high selectivity. Furthermore, the catalyst has high stability and its performance will not significantly decrease with long-term use.

[0010] To achieve the above objectives, the present invention provides a method for catalytic ammonolysis of bis(hexamethylene)triamine, the method comprising: in an atmosphere of ammonia and hydrogen, in the presence of a catalyst, causing bis(hexamethylene)triamine to undergo an ammonolysis reaction;

[0011] The catalyst comprises a support and a main active component and an auxiliary agent supported on the support. The main active component is Ni, the auxiliary agent includes La, and the support comprises alumina, with the alumina content being 50-80 wt% of the total weight of the support.

[0012] The method provided by this invention can efficiently catalyze the ammonolysis of bis(hexamethylene)triamine, resulting in a high conversion rate and high selectivity for the target products hexamethylenediamine and cycloheximine, demonstrating strong catalytic performance. Furthermore, the catalyst exhibits strong stability, with no significant performance degradation over long-term use. Detailed Implementation

[0013] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0014] In a first aspect, the present invention provides a method for catalytic ammonolysis of bis(hexamethylene)triamine, characterized in that the method comprises: in an atmosphere of ammonia and hydrogen, in the presence of a catalyst, causing bis(hexamethylene)triamine to undergo an ammonolysis reaction;

[0015] The catalyst comprises a support and a main active component and an auxiliary agent supported on the support. The main active component is Ni, the auxiliary agent includes La, and the support comprises alumina, with the alumina content being 50-80 wt% of the total weight of the support.

[0016] The main active component Ni and the auxiliary elements mentioned above can exist on the catalyst in a reduced state (such as elemental form) and in oxide form, wherein at least a portion of Ni exists on the catalyst in a reduced state. Before use, the catalyst can be activated to ensure that at least a portion of Ni exists in a reduced state.

[0017] The inventors of this invention discovered in their research that the catalyst described above possesses suitable surface acidity and basicity, exhibiting high catalytic activity and selectivity when applied to the catalytic ammonolysis reaction. In particular, it demonstrates high conversion rate in the catalytic ammonolysis reaction of bis(hexamethylene)triamine, and can yield cycloheximine and hexamethylenediamine with high selectivity. Furthermore, the catalyst exhibits strong stability, and its performance does not significantly change with long-term use.

[0018] According to the present invention, preferably, the Ni content is 10-40 wt% based on the total weight of the catalyst, more preferably 12-35 wt% (e.g., it can be 12 wt%, 15 wt%, 18 wt%, 20 wt%, 22 wt%, 25 wt%, 28 wt%, 30 wt%, 32 wt%, 35 wt%).

[0019] According to the present invention, preferably, the total content of the auxiliary elements is 1-10 wt% (e.g., 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%) based on the total weight of the catalyst.

[0020] According to the present invention, preferably, the content of each auxiliary element is 0.1-10 wt% based on the total weight of the catalyst, more preferably 0.3-6 wt% (e.g., it can be 0.3 wt%, 0.5 wt%, 0.7 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%).

[0021] Within the aforementioned preferred range, the catalyst's hydrogenation, dehydrogenation, ammoniation, and adsorption capabilities are further balanced and improved, resulting in better conversion rates and selectivity of the catalytic reaction.

[0022] According to the present invention, preferably, the adjuvant further includes at least one element selected from Group IIIB, Group VIB, Group VIIB and Group IIIA.

[0023] According to the present invention, preferably, the auxiliary agent is selected from at least one of Ce, Nd, Mo, W, Mn, Re, B, Ga and In, more preferably at least one of B and In.

[0024] According to the present invention, preferably, the additives are La, B and In, and the elemental weight ratio of Ni, La, In and B is 100:(3-30):(0-15):(0-2).

[0025] By selecting the above-mentioned auxiliaries, or by meeting the above-mentioned mass ratios, side reactions can be further reduced and the selectivity of hexamethylenediamine and cycloheximine can be further improved.

[0026] According to the present invention, preferably, the alumina content is 52-75 wt% of the total weight of the carrier (for example, it can be 52 wt%, 55 wt%, 58 wt%, 60 wt%, 62 wt%, 64 wt%, 66 wt%, 68 wt%, 70 wt%, 72 wt%, 74 wt%, 75 wt%).

[0027] According to the present invention, preferably, the support further includes at least one selected from silica, molecular sieve, aluminum silicate, hydroxyapatite, and calcium oxide. More preferably, the support further includes silica and calcium oxide.

[0028] Under the conditions of the above content and carrier components, the dispersion of the main active component and the auxiliary agent on the carrier can be further enhanced, and the strength of the carrier can also be further improved.

[0029] According to the present invention, preferably, the ammonia adsorption capacity of the catalyst is 0.05-0.3 mmol / g. Within this range, the number of acidic and basic sites on the support is more suitable, avoiding the problems of insufficient adsorption of adsorbate species, insufficient catalytic activation capacity, and difficulty in forming an active activated state. It also avoids the problems of competitive adsorption mismatch caused by unreasonable acid-base site distribution, resulting in excessively strong catalytic activation capacity and more side reactions. Within the above range, the acid-base site distribution is more reasonable. The ammonia adsorption capacity of the support can be determined by first saturating the support with ammonia, then using a programmed temperature increase to desorb the ammonia from the support, and detecting the amount of desorbed ammonia to obtain the ammonia adsorption capacity.

[0030] The preparation method of the catalyst is not particularly limited, as long as the active component and auxiliary agent can be loaded onto the support to obtain a catalyst with the above composition. The specific operation of the preparation process is also not particularly limited; for example, the loading method can employ commonly used methods in the art, such as precipitation or impregnation.

[0031] Furthermore, the catalyst of this invention can be used in any form, such as extruded strips or tablets, or in powder form. The support can be pre-formed and then impregnated with a solution containing the main active component precursor and auxiliary precursor; alternatively, the support can be kneaded together or precipitated together with a metal compound and then formed; or it can be impregnated and then formed into the desired shape, such as clover, four-leaf clover, cylinder, toothed ball, hollow strip, hollow sphere, etc. In continuous ammoniation reactions, shaped catalysts (catalysts obtained by extrusion or tableting) are generally required.

[0032] For example, the preparation method of the above catalyst may include:

[0033] (1) A mixture containing an alumina precursor and optionally other carrier precursors is sequentially subjected to molding, first drying and first calcination, wherein the other carrier precursors include at least one of silica precursor, molecular sieve precursor, aluminum silicate precursor, hydroxyapatite precursor and calcium oxide precursor.

[0034] (2) The product after the first calcination is immersed in an immersion solution containing the main active component precursor and the auxiliary agent precursor;

[0035] Preferably, the impregnation is carried out in multiple stages, and after each impregnation, the material is subjected to a second drying and a second roasting.

[0036] (3) The material obtained after impregnation is reduced.

[0037] Other carrier precursors can be prepared into an aqueous solution first, and then mixed with the alumina precursor in a kneader. Kneading aids (such as nitric acid, phosphoric acid, hydrofluoric acid, acetic acid, the amount of which can be conventionally selected in the field, such as 2-15g of kneading aid relative to 100g of alumina precursor) can be added together to carry out subsequent molding (such as extrusion) and other steps.

[0038] It is understandable that the amount of each substance in step (1) is determined to satisfy the content of each component on the catalyst.

[0039] The alumina precursor can be boehmite, and the specific surface area of ​​the boehmite can be 280-330 m². 2 / g, with a pore volume of 0.9-1.3 ml / g. The pseudoboehmite can be prepared by at least one of the following methods: carbonization, organoaluminum hydrolysis, aluminum sulfate, and nitric acid. Other carrier precursors, i.e., substances that can be converted into other carrier components or contain other carrier components, such as silica sol as a silica precursor and calcium nitrate (tetrahydrate) as a calcium oxide precursor. The conditions for the first drying and the first calcination can also be conventionally selected in the art. The temperature for the first drying can be 70-140℃. The time for the first drying can be 3-7 h. The first calcination can be carried out at 800-1000℃ for 3-8 h.

[0040] In step (2), the precursor of the main active component and the precursor of the auxiliary agent can each be independently selected from at least one of their nitrates, sulfates, nitrates, and oxalates. Using the above-described method of loading the main active component and auxiliary agent by impregnation, each salt is preferably used in the form of a salt solution. It is understood that in practical applications, the salts can be the corresponding hydrated salts; for example, nickel sulfate can be nickel sulfate hexahydrate. The solvent for the salt solution can be water or other organic solvents, such as ethanol. The impregnation of the carrier with the metal salt solution can be carried out in any desired order, or it can be carried out continuously with multiple solutions containing one or more metal salts. All or a single impregnation step can be carried out in several steps, and the impregnation order can also be changed. A suitable concentration of the metal salt solution is selected to load a predetermined amount of metal onto the carrier. The specific impregnation method can be the equal-volume impregnation method commonly used in the art. Furthermore, other substances can be artificially added to the impregnation solution to adjust the acidic and basic sites of the carrier itself, for example, boron-containing compounds, fluorine-containing compounds, phosphorus-containing compounds, sulfur-containing compounds, or selenium-containing compounds. The aforementioned compounds can also be added during the carrier molding process or catalyst molding process for modification. Alternatively, these compounds or other forms of the corresponding elements can be introduced during the production of the carrier raw materials. These methods of carrier modification are merely illustrative and are not limited to these methods; other methods can be used.

[0041] The conditions for the second drying and second calcination can also be conventionally chosen in the field. The second drying should be based on the premise that the moisture content after drying does not affect subsequent decomposition, and the required drying time can be set according to the specific temperature, catalyst quantity, and equipment performance. For example, the temperature for each second drying can be independently set at 60-150℃, particularly 100-130℃; the time can be independently set at 2-8 hours, particularly 3-7 hours. The temperature for each second calcination can be independently set at 150-600℃, particularly 300-500℃; the time can be independently set at 2-8 hours, particularly 3-6 hours. It is understood that the second calcination can decompose the metal salt supported on the carrier into metal oxides.

[0042] The reduction conditions may include: in the presence of reducing gas, heating the material in the first stage to 130-160°C and maintaining the temperature for 2-8 hours; then heating the material in the second stage to 400-500°C and maintaining the temperature for 4-6 hours.

[0043] The heating rates of the first and second stages of heating can be independent, ranging from 5 to 50 °C / h, preferably from 10 to 20 °C / h. The heating rates of the first and second stages can be the same or different, but are preferably the same.

[0044] The reducing gas can be a nitrogen-hydrogen mixture, in which the hydrogen content can be 0.8-55% by volume, and the space velocity of the nitrogen-hydrogen mixture can be 500-5000 m / s. 3 / (m 3 ·h -1 ).

[0045] It is understood that reduction can reduce at least part of a metal oxide to a catalytically active elemental metal; this process can also be called activation. During reduction, the reducing gas can be hydrogen or a mixture of hydrogen and nitrogen. The hydrogen content in the hydrogen-nitrogen mixture can be arbitrary; a mixture with a high hydrogen content can be used. If a mixture with a high hydrogen content is used, or if reduction is performed with pure hydrogen, the heating rate needs to be strictly controlled, and the heating process should be slow. Therefore, it is preferable to perform reduction using a nitrogen-hydrogen mixture with a slightly lower hydrogen content, as this makes the reduction process easier to control, especially the temperature, and prevents the catalyst bed from overheating. Under the aforementioned higher space velocity conditions, the heat generated by the reaction can also be quickly removed in a timely manner, maintaining a stable catalyst bed temperature and preventing overheating that could damage the catalyst. Those skilled in the art will understand that the specific operating conditions of the above reduction process can be adjusted according to the circumstances, as long as reduction can be achieved.

[0046] After the aforementioned isothermal stage, the material can be slowly cooled to room temperature, for example, at a rate of 5-20°C / hour. Once cooled to room temperature, switch to nitrogen gas and gradually mix in air, gradually increasing the air volume to increase the oxygen content in the mixture. Under oxygen-containing conditions, the elemental metal transforms into metal oxide, passivating the catalyst (by coating the catalyst surface with a thin oxide film to protect it) for storage. Before use, the oxide on the catalyst surface is reduced. The oxygen volume is adjusted according to changes in catalyst temperature to prevent the catalyst bed temperature from becoming too high, for example, not exceeding 50°C. If the catalyst is reduced in situ in the reactor, it can be used once the temperature drops to the reaction temperature after reduction.

[0047] According to the present invention, in order to further improve the conversion rate and selectivity of the reaction, the preferred conditions for the ammonolysis reaction include: a temperature of 145-265°C, more preferably 168-235°C; a pressure of 8-28 MPa, more preferably 14-24 MPa; and a feed liquid hourly space velocity of 0.005-1.5 h⁻¹ for bis(hexamethylene)triamine. -1 More preferably, it is 0.1-0.9h. -1 The molar ratio of hydrogen, ammonia, and bis(hexamethylene)triamine is (1-18):(50-165):1, more preferably (1.5-12):(70-120):1. The pressure is the pressure of the reaction system.

[0048] According to the present invention, preferably, the bis(hexamethylene)triamine is used in the form of a bis(hexamethylene)triamine solution, wherein the mass concentration of the bis(hexamethylene)triamine in the solution is 20-50 wt%. Ammonia can be used in the form of liquid ammonia.

[0049] According to the present invention, preferably, the solvent of the solution is selected from at least one of water, 1,4-epoxybutane, and 1,4-dioxane. The inventors of the present invention have also found that using the above-mentioned solvent can further improve the conversion rate of bis(hexamethylene)triamine, and the conversion rates of cycloheximine and hexamethylenediamine, reduce the amount of heavy components generated, and thereby extend the catalyst lifespan.

[0050] The present invention will be described in detail below through examples. In the following examples, the dry basis (Al2O3) content of the pseudoboehmite powder is approximately 70% by weight. The silica sol was purchased from Qingdao Ocean Chemical Plant, model JN-40.

[0051] In the following examples, the method for determining the ammonia adsorption capacity is NH3-TPD, as detailed below:

[0052] Testing instrument: Automated Catalyst Characterization System (Autochem 2920), product of Microlithics, USA.

[0053] Test conditions: Accurately weigh approximately 0.1 g of sample and place it in a sample tube. Under He gas purging conditions, raise the temperature to 600 °C at 10 °C / min, hold for 1 h, lower the temperature to 120 °C, then change the gas to a 10% NH3-He mixture, adsorb for 60 min, then switch back to He gas purging for 1 h. After the baseline stabilizes, start counting, raise the temperature to 600 °C at 10 °C / min, hold for 30 min, stop recording, and complete the experiment. Calculate the ammonia adsorption capacity by integrating the peak area.

[0054] In the following embodiments and preparation examples, the reduction method is as follows: in a nitrogen-hydrogen mixed gas atmosphere (where the hydrogen content is 20-30% by volume and the space velocity of the nitrogen-hydrogen mixed gas is 1000-2000 m / s²), the reduction method is as follows: 3 / (m 3 ·h -1 The process involves heating and reducing the temperature. First, the temperature is increased to 130-160℃ at a rate of 20-30℃ / h and held at a constant temperature for 3-6 hours. Then, the temperature is increased to 400-480℃ at a rate of 20-30℃ / h and reduced at 400℃ for 4-6 hours.

[0055] Example 1

[0056] (1) Weigh the pseudoboehmite (produced by the aluminum sulfate method, with a specific surface area of ​​320 m²).2 The mixture consisted of 106.25 g of a mixture with a pore volume of 1.25 ml / g, 45.0 g of silica sol (JN-40), and 35.79 g of calcium nitrate tetrahydrate. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 41.32 g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution consisting of 27.55 g of water, 5.33 g of nitric acid, and 3.20 g of phosphoric acid was added, and the mixture was kneaded and extruded into a clover shape. This was dried at 120°C for 4 hours, followed by calcination at 860°C in a muffle furnace for 5 hours. After cooling, the carrier was obtained.

[0057] (2) 98.53 g of nickel sulfate hexahydrate (industrial grade, 98% purity), 4.55 g of lanthanum acetate monohydrate, and 2.72 g of indium nitrate pentahydrate were added to 138.37 mL of water to prepare an aqueous solution. The solution was loaded onto the 75.2 g support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 120 °C for 4 hours and then calcined at 380 °C for 4 hours. Then, reduction was performed to obtain catalyst A-1. The ammonia adsorption capacity of the catalyst was determined to be 0.19 mmol / g using the ammonia-desorption assay method described above.

[0058] Example 2

[0059] (1) Weigh the pseudoboehmite (produced by aluminum sulfate method, specific surface area 312m²). 2 The sample consisted of 89.86 g of pseudoboehmite (1.10 ml / g pore volume), 86.25 g of silica sol (JN-40), and 14.74 g of calcium nitrate tetrahydrate. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 28.25 g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution of 18.84 g water, 4.49 g nitric acid, and 2.7 g hydrofluoric acid was then added, and the mixture was kneaded and extruded into strips. These strips were dried at 120°C for 6 hours, followed by calcination at 930°C in a muffle furnace for 3 hours. After cooling, the carrier was obtained.

[0060] (2) 125.4 g of nickel sulfate hexahydrate (industrial grade, 98% purity), 12.51 g of lanthanum acetate monohydrate, and 4.77 g of indium nitrate pentahydrate were added to 119.78 mL of water to prepare an aqueous solution. The solution was loaded onto 65.1 g of the support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 110 °C for 4 hours and then calcined at 360 °C for 6 hours. Then, reduction was performed to obtain catalyst A-2. The ammonia adsorption capacity of the catalyst was determined to be 0.26 mmol / g using the ammonia-desorption assay method described above.

[0061] Example 3

[0062] (1) Weigh the pseudoboehmite (produced by the aluminum sulfate method, with a specific surface area of ​​308 m²). 2 The mixture consisted of 94.93 g of a mixture with a pore volume of 1.21 ml / g, 68.75 g of silica sol (JN-40), and 29.48 g of calcium nitrate tetrahydrate. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 32.21 g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution consisting of 21.47 g of water, 6.64 g of acetic acid, and 2.85 g of phosphoric acid was added, and the mixture was kneaded and extruded into a clover shape. This was dried at 120°C for 4 hours, followed by calcination at 880°C in a muffle furnace for 5 hours. After cooling, the carrier was obtained.

[0063] (2) 107.49 g of nickel sulfate hexahydrate (industrial grade, 98% purity), 2.28 g of lanthanum acetate monohydrate, and 5.11 g of indium nitrate pentahydrate were added to 135.24 mL of water to prepare an aqueous solution. The solution was loaded onto 73.5 g of the support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 120 °C for 4 hours and then calcined at 400 °C for 4 hours. Then, reduction was performed to obtain catalyst A-3. The ammonia adsorption capacity of the catalyst was determined to be 0.21 mmol / g using the ammonia-desorption assay method described above.

[0064] Example 4

[0065] (1) Weigh the pseudoboehmite (produced by carbonization method, specific surface area 289m²). 2 The mixture consisted of 103.19 g of a mixture with a pore volume of 0.98 ml / g, 59 g of silica sol (JN-40), and 21.90 g of calcium nitrate tetrahydrate. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 46.86 g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution of 31.24 g of water, 5.16 g of nitric acid, and 3.10 g of hydrofluoric acid was added, and the mixture was kneaded and extruded into a clover shape. This was dried at 120°C for 4 hours, followed by calcination at 810°C in a muffle furnace for 8 hours. After cooling, the carrier was obtained.

[0066] (2) 106.0 g of nickel acetate tetrahydrate (industrial grade, 98% purity), 7.96 g of lanthanum acetate monohydrate, 1.72 g of boric acid, and 4.08 g of indium nitrate pentahydrate were added to 128.8 mL of water to prepare an aqueous solution. The solution was loaded onto 70.0 g of the support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 120 °C for 4 hours and then calcined at 390 °C for 4 hours. Then, reduction was performed to obtain catalyst A-4. The ammonia adsorption capacity of the catalyst was determined to be 0.29 mmol / g using the ammonia-desorption assay method described above.

[0067] Example 5

[0068] (1) Weigh the pseudoboehmite (produced by the aluminum sulfate method, with a specific surface area of ​​308 m²). 2 / g, pore volume 1.21ml / g) 108.70g and silica sol (JN-40) 56.68g. The pseudoboehmite was placed in a kneader, and the weighed silica sol was added to 52.17g of water to prepare a solution. This solution was then added to the pseudoboehmite in the kneader and stirred thoroughly. Next, an aqueous solution of 31.24g water, 5.43g nitric acid, and 3.26g phosphoric acid was added, and the mixture was kneaded and extruded into a clover shape. This was dried at 120℃ for 4 hours, followed by calcination at 890℃ in a muffle furnace for 4 hours. After cooling, the carrier was obtained.

[0069] (2) 84.80 g of nickel acetate tetrahydrate (industrial grade, 98% purity), 11.38 g of lanthanum acetate monohydrate, and 6.81 g of indium nitrate pentahydrate were added to 134.32 mL of water to prepare an aqueous solution. The solution was then loaded onto the 73.0 g support obtained in step (1) using a spraying method in two separate applications. After each spraying, the support was dried at 120 °C for 4 hours and then calcined at 380 °C for 6 hours. Reduction was then performed to obtain catalyst A-5. The ammonia adsorption capacity of the catalyst was determined to be 0.16 mmol / g using the ammonia-desorption assay method described above.

[0070] Example 6

[0071] (1) Weigh the pseudoboehmite (produced by carbonization method, specific surface area 295m²). 2 / g, pore volume 0.96ml / g) 99.71g, silica sol (JN-40) 68.0g and calcium nitrate tetrahydrate 16.84g. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 35.35g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution of 23.56g water, 6.98g acetic acid, and 2.99g phosphoric acid was then added, and the mixture was kneaded and extruded into toothed spheres. These spheres were dried at 120℃ for 4 hours, then calcined in a muffle furnace at 960℃ for 3 hours. After cooling, the carrier was obtained.

[0072] (2) 127.2 g of nickel acetate tetrahydrate (industrial grade, 98% purity), 7.96 g of lanthanum acetate monohydrate, and 5.11 g of indium nitrate pentahydrate were added to 129.72 mL of water to prepare an aqueous solution. The solution was loaded onto 70.5 g of the support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 120 °C for 6 hours and then calcined at 410 °C for 3 hours. Then, reduction was performed to obtain catalyst A-6. The ammonia adsorption capacity of the catalyst was determined to be 0.15 mmol / g using the ammonia-desorption assay method described above.

[0073] Example 7

[0074] (1) Weigh the pseudoboehmite (produced by the aluminum sulfate method, with a specific surface area of ​​308 m²). 2 The mixture consisted of 76.52 g of pseudoboehmite (1.21 ml / g pore volume), 93.0 g of silica sol (JN-40), and 42.11 g of calcium nitrate tetrahydrate. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 17.02 g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution consisting of 11.35 g of water, 5.33 g of nitric acid, and 3.20 g of phosphoric acid was added, and the mixture was kneaded and extruded into a clover shape. This was dried at 120°C for 4 hours, followed by calcination at 920°C in a muffle furnace for 6 hours. After cooling, the carrier was obtained.

[0075] (2) 101.76 g of nickel acetate tetrahydrate (industrial grade, 98% purity), 9.10 g of lanthanum acetate monohydrate, and 6.13 g of indium nitrate pentahydrate were added to 129.17 mL of water to prepare an aqueous solution. The solution was loaded onto 70.2 g of the support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 120 °C for 3 hours and then calcined at 420 °C for 4 hours. Then, reduction was performed to obtain catalyst A-7. The ammonia adsorption capacity of the catalyst was determined to be 0.25 mmol / g using the ammonia-desorption assay method described above.

[0076] Example 8

[0077] (1) Weigh the pseudoboehmite (produced by aluminum sulfate method, specific surface area 312m²). 2 The mixture consisted of 119.42 g of a mixture with a pore volume of 1.10 ml / g, 25.25 g of silica sol (JN-40), and 31.58 g of calcium nitrate tetrahydrate. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 55.40 g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution consisting of 36.93 g of water, 5.33 g of nitric acid, and 3.20 g of phosphoric acid was added, and the mixture was kneaded and extruded into a clover shape. This was dried at 120°C for 4 hours, followed by calcination at 900°C in a muffle furnace for 5 hours. After cooling, the carrier was obtained.

[0078] (2) 93.28 g of nickel acetate tetrahydrate (industrial grade, 98% purity), 6.83 g of lanthanum acetate monohydrate, and 1.70 g of indium nitrate pentahydrate were added to 137.08 mL of water to prepare an aqueous solution. The solution was loaded onto the 74.5 g support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 120 °C for 4 hours and then calcined at 400 °C for 4 hours. Then, reduction was performed to obtain catalyst A-8. The ammonia adsorption capacity of the catalyst was determined to be 0.14 mmol / g using the ammonia-desorption assay method described above.

[0079] Example 9

[0080] (1) Weigh the pseudoboehmite (produced by carbonization method, specific surface area 295m²). 2 / g, pore volume 0.96ml / g) 99.71g, silica sol (JN-40) 68.0g and calcium nitrate tetrahydrate 16.84g. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 35.35g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution of 23.56g water, 6.98g acetic acid, and 2.99g phosphoric acid was then added, and the mixture was kneaded and extruded into toothed spheres. These spheres were dried at 120℃ for 4 hours, then calcined in a muffle furnace at 960℃ for 3 hours. After cooling, the carrier was obtained.

[0081] (2) 63.60 g of nickel acetate tetrahydrate (industrial grade, 98% purity), 4.55 g of lanthanum acetate monohydrate, and 4.43 g of indium nitrate pentahydrate were added to 150.33 mL of water to prepare an aqueous solution. The solution was loaded onto 81.7 g of the support obtained in step (1) using an equal-volume impregnation method in two separate applications. After each impregnation, the solution was dried at 120 °C for 4 hours and then calcined at 430 °C for 4 hours. Then, reduction was performed to obtain catalyst A-9. The ammonia adsorption capacity of the catalyst was determined to be 0.15 mmol / g using the ammonia-desorption assay method described above.

[0082] Example 10

[0083] (1) Weigh boehmite (produced by aluminum sulfate method with a specific surface area of ​​312 m²) 2 The mixture consisted of 89.86 g of pseudoboehmite (1.10 ml / g pore volume), 86.25 g of silica sol (JN-40), and 14.74 g of calcium nitrate tetrahydrate. The pseudoboehmite was placed in a kneader. The weighed silica sol and calcium nitrate tetrahydrate were added to 28.25 g of water to prepare a solution, which was then added to the pseudoboehmite in the kneader and stirred thoroughly. An aqueous solution of 18.84 g water, 4.49 g nitric acid, and 2.7 g hydrofluoric acid was added, and the mixture was kneaded and extruded into strips. These strips were dried at 120°C for 6 hours, then calcined in a muffle furnace at 930°C for 3 hours. After cooling, the carrier was obtained.

[0084] (2) 148.4 g of nickel acetate tetrahydrate (industrial grade, 98% purity) and 6.83 g of lanthanum acetate monohydrate were added to 114.08 mL of water to prepare an aqueous solution. The solution was loaded onto 62.0 g of the support obtained in step (1) in two equal-volume impregnation methods. After each impregnation, the solution was dried at 120 °C for 4 hours and then calcined at 400 °C for 4 hours. Then, reduction was performed to obtain catalyst A-10. The ammonia adsorption capacity of the catalyst was determined to be 0.26 mmol / g using the ammonia-desorption assay method described above.

[0085] Comparative Example 1

[0086] (1) Weigh the pseudoboehmite (produced by carbonization method, specific surface area 289m²). 2 The following ingredients were prepared: 103.19 g of silica sol (JN-40) (pore volume 0.98 ml / g), 59 g of silica sol, and 21.90 g of calcium nitrate tetrahydrate. The weighed silica sol and calcium nitrate tetrahydrate were added to 46.86 g of water to prepare a solution. This solution was then added to boehmite in a kneader and stirred thoroughly. An aqueous solution of 31.24 g of water, 5.16 g of nitric acid, and 3.10 g of hydrofluoric acid was added and kneaded and extruded into a clover shape. The solution was dried at 120 °C for 4 h and then calcined at 900 °C in a muffle furnace for 4 h. After cooling, the carrier was obtained.

[0087] (2) 93.28 g of nickel acetate tetrahydrate (industrial grade, 98% purity) and 8.51 g of indium nitrate pentahydrate were added to 138.92 mL of water to prepare a solution. The solution was then loaded onto the obtained 75.5 g support in two separate spraying operations. After each spraying, the support was dried at 120 °C for 4 hours and then calcined at 400 °C for 4 hours. Reduction was then performed to obtain catalyst B-1. The ammonia adsorption capacity of the catalyst was determined to be 0.27 mmol / g using the ammonia-desorption assay method described above.

[0088] Comparative Example 2

[0089] (1) Weigh the pseudoboehmite (produced by the aluminum sulfate method, with a specific surface area of ​​320 m²). 2 The following ingredients were prepared: 124.64 g of silica sol (JN-40) (pore volume 1.25 ml / g), 24.25 g of silica sol, and 18.11 g of calcium nitrate tetrahydrate. The weighed silica sol and calcium nitrate tetrahydrate were added to 58.57 g of water to prepare a solution, which was then added to boehmite in a kneader and stirred thoroughly. An aqueous solution of 39.05 g of water, 6.23 g of nitric acid, and 3.74 g of phosphoric acid was added, and the mixture was kneaded and extruded into cylindrical strips. The strips were dried at 120 °C for 4 h, and then calcined at 850 °C for 5 h in a muffle furnace. After cooling, the carrier was obtained.

[0090] (2) 110.24 g of nickel acetate tetrahydrate (industrial grade, 98% purity), 9.10 g of lanthanum acetate monohydrate, and 3.40 g of indium nitrate pentahydrate were added to 126.96 mL of water to prepare a solution. The solution was loaded onto the obtained 69.0 g support in two equal-volume impregnation methods. After each impregnation, the support was dried at 120 °C for 4 hours and then calcined at 380 °C for 4 hours. Then, reduction was performed to obtain catalyst B-2. The ammonia adsorption capacity of the catalyst was determined to be 0.44 mmol / g using the ammonia-desorption assay method described above.

[0091] Comparative Example 3

[0092] (1) Weigh boehmite (produced by aluminum sulfate method with a specific surface area of ​​312 m²) 2The following ingredients were prepared: 48.90 g of silica sol (JN-40) (pore volume 1.10 ml / g), 103.75 g of silica sol (JN-40), and 40.42 g of calcium nitrate tetrahydrate. The weighed silica sol and calcium nitrate tetrahydrate were added to 11.42 g of water to prepare a solution. The solution was then added to boehmite in a kneader and stirred thoroughly. An aqueous solution of 7.88 g of water, 3.54 g of nitric acid, and 2.13 g of phosphoric acid was added and kneaded and extruded into a clover shape. The solution was dried at 120 °C for 4 h and then calcined at 800 °C for 6 h in a muffle furnace. After cooling, the carrier was obtained.

[0093] (2) 161.23 g of nickel sulfate hexahydrate (industrial grade, 98% purity), 4.55 g of lanthanum acetate monohydrate, and 3.40 g of indium nitrate pentahydrate were added to 112.24 mL of water to prepare a solution. The solution was loaded onto the obtained 61.0 g support in two equal-volume impregnation methods. After each impregnation, the support was dried at 120 °C for 4 hours and then calcined at 400 °C for 4 hours. Then, reduction was performed to obtain catalyst B-3. The ammonia adsorption capacity of the catalyst was determined to be 0.12 mmol / g using the ammonia-desorption assay method described above.

[0094] Comparative Example 4

[0095] (1) Weigh the pseudoboehmite (produced by the aluminum sulfate method, with a specific surface area of ​​320 m²). 2 The following ingredients were prepared: 195.65 g of silica sol (JN-40) (pore volume 1.25 ml / g), 67.50 g of silica sol, and 29.48 g of calcium nitrate tetrahydrate. The weighed silica sol and calcium nitrate tetrahydrate were added to 27.35 g of water to prepare a solution, which was then added to boehmite in a kneader and stirred thoroughly. An aqueous solution of 18.23 g of water, 4.78 g of nitric acid, and 2.87 g of phosphoric acid was added, and the mixture was kneaded and extruded into a clover shape. The clover shape was dried at 120 °C for 4 h, and then calcined at 920 °C in a muffle furnace for 4 h. After cooling, the carrier was obtained.

[0096] (2) 111.96 g of nickel sulfate hexahydrate (industrial grade, 98% purity) was added to 138.0 mL of water to prepare a solution. The solution was loaded onto the obtained 75.0 g support in two equal-volume impregnation methods. After each impregnation, the support was dried at 120 °C for 4 hours and then calcined at 420 °C for 4 hours. Then, reduction was carried out to obtain catalyst B-4. The ammonia adsorption capacity of the catalyst was determined to be 0.20 mmol / g using the ammonia-desorption assay method described above.

[0097] Comparative Example 5

[0098] The procedure was carried out according to Example 1, except that in step (2), indium nitrate pentahydrate was not added, nickel sulfate hexahydrate was used in an amount of 101.22 g, and lanthanum acetate monohydrate was used in an amount of 5.01 g. Catalyst B-5 was thus prepared.

[0099] Comparative Example 6

[0100] The procedure was carried out according to Example 1, except that the silica sol and calcium nitrate tetrahydrate were replaced with boehmite (i.e., the amount of boehmite used was 144.93 g). The resulting catalyst product was designated B-6.

[0101] Test Example 1

[0102] The catalyst products prepared in the above examples and comparative examples were subjected to the following measurements:

[0103] The weights of alumina, silica, and calcium oxide, as well as the contents of doping elements in the carrier, were calculated using X-ray fluorescence analysis (XRF).

[0104] The content of metal elements supported on the catalyst was analyzed by X-ray fluorescence analysis (XRF). The results are shown in Table 1-2.

[0105] Table 1

[0106]

[0107] Table 2

[0108]

[0109]

[0110] In the following test examples, all sampling and analysis were performed using gas chromatography. The conversion rate and selectivity were calculated as follows:

[0111] BHT conversion rate:

[0112]

[0113] The selectivity of cyclohexylimine is:

[0114]

[0115] The selectivity of hexamethylenediamine is:

[0116]

[0117] The selectivity of C12 amines is:

[0118]

[0119] The selectivity of C18 amines is:

[0120]

[0121] Test Example 2

[0122] The catalysts prepared in the above examples and comparative examples were subjected to the following experiments:

[0123] 100 mL of catalyst was measured and loaded into a fixed-bed reactor. Activation was performed with hydrogen at 230 °C for 2 hours, followed by cooling to 195 °C. The system pressure was increased to 16.0 MPa using hydrogen. Ammonia, after being metered and preheated, was introduced into the upper part of the reactor. A 25 wt% solution of 1,4-dioxane (BHT) was also metered into the upper part of the reactor. Hydrogen was introduced simultaneously via a gas mass flow meter. The molar ratio of hydrogen to ammonia to BHT was 2:90:1, and the liquid hourly space velocity (LHSV) of BHT was 0.3 h⁻¹. -1 The three substances were reacted in a catalyst bed. After the reaction stabilized, samples were taken for analysis, and the results are listed in Table 3.

[0124] Table 3

[0125]

[0126] Test Example 3

[0127] 100 mL of catalyst A-8 prepared in Example 8 was measured and placed in a fixed-bed reactor. Activation and reaction were carried out in the manner described in Test Example 2, but the temperature, pressure, molar ratio of hydrogen:ammonia:BHT, and liquid hourly space velocity of BHT were changed. The reaction sampling and analysis results are shown in Table 4.

[0128] Table 4

[0129]

[0130] Test Example 4

[0131] 100 mL of catalyst A-9 prepared in Example 9 was measured and placed in a fixed-bed reactor. It was activated with hydrogen at 230°C for 4 hours, then cooled to 185°C. The system pressure was increased to 17.5 MPa using hydrogen. Ammonia, after being metered and preheated, was introduced into the upper part of the reactor using a metering pump. A 30 wt% BHT solution of 1,4-dioxane was also metered into the upper part of the reactor. Hydrogen was introduced simultaneously via a gas mass flow meter. The molar ratio of hydrogen to ammonia to BHT was 3:95:1, and the liquid hourly space velocity (LHSV) of BHT was 0.3 h⁻¹. -1 The three substances were reacted in a catalyst bed. After the reaction stabilized, samples were taken for analysis at regular intervals. The analysis results are listed in Table 5.

[0132] Table 5

[0133]

[0134] Furthermore, the inventors of this invention have discovered that the catalysts prepared in the embodiments of this invention, particularly those prepared in Examples 1-7, also exhibit high conversion rates and selectivity under the conditions of Test Example 3. Moreover, the catalysts prepared in Examples 1-7, similar to those prepared in Example 9, also possess high stability.

[0135] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for catalytic ammonolysis of bis(hexamethylene)triamine, characterized in that, The method includes: subjecting bis(hexamethylene)triamine to ammonolysis in an atmosphere of ammonia and hydrogen in the presence of a catalyst; The catalyst comprises a support and a main active component and an auxiliary agent supported on the support. The main active component is Ni, and the auxiliary agent is La, or La and In, or La, In and B. The Ni content is 10-40 wt% by total weight of the catalyst, and the total content of the auxiliary agent elements is 1-10 wt%. The carrier is composed of alumina, silicon dioxide and calcium oxide, or alumina and silicon dioxide, with the alumina content being 50-80 wt% of the total weight of the carrier.

2. The method according to claim 1, wherein, The Ni content is 12-35 wt% based on the total weight of the catalyst.

3. The method according to claim 1 or 2, wherein, The content of each auxiliary element is 0.1-10 wt% based on the total weight of the catalyst.

4. The method according to claim 3, wherein, The content of each auxiliary element is 0.3-6 wt% based on the total weight of the catalyst.

5. The method according to claim 1, wherein, The additives are La, B and In, and the elemental weight ratio of Ni, La, In and B is 100:(3-30):(0-15):(0-2).

6. The method according to claim 1, wherein, The alumina content is 52-75 wt% of the total weight of the carrier.

7. The method according to claim 1, wherein, The ammonia adsorption capacity of the catalyst is 0.05-0.3 mmol / g.

8. The method according to claim 1, wherein, The conditions for the ammonolysis reaction include: a temperature of 145-265℃; a pressure of 8-28 MPa; and a feed liquid hourly space velocity (LHSV) of 0.005-1.5 h⁻¹ for bis(hexamethylene)amine. -1 The molar ratio of hydrogen, ammonia and bis(hexamethylene)triamine is (1-18):(50-165):

1.

9. The method according to claim 8, wherein, The conditions for the ammonolysis reaction include: a temperature of 168-235℃; a pressure of 14-24 MPa; and a feed liquid hourly space velocity (LHSV) of 0.1-0.9 h⁻¹ for bis(hexamethylene)amine. -1 The molar ratio of hydrogen, ammonia and bis(hexamethylene)triamine is (1.5-12):(70-120):

1.

10. The method according to claim 1 or 8, wherein, The bis(hexamethylene)triamine is used in the form of a bis(hexamethylene)triamine solution, wherein the mass concentration of the bis(hexamethylene)triamine in the solution is 20-50 wt%.

11. The method according to claim 10, wherein, The solvent of the solution is selected from at least one of water, 1,4-epoxybutane and 1,4-dioxane.

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