Polyether amine catalyst, its preparation method and application

Abstract

The application discloses a polyether amine catalyst and a preparation method and application thereof. The polyether amine catalyst is a carbon-nitrogen doped multi-metal catalyst, and the multi-metal includes nickel, molybdenum and aluminum. The polyether amine catalyst has the advantages of high reaction conversion rate and selectivity, long service life and simple preparation process.

Description

Technical Field

[0001] This invention belongs to the field of polyetheramine technology, specifically relating to a polyetheramine catalyst, its preparation method, and its application. Background Technology

[0002] Polyetheramines, also known as amino-terminated polyethers, are a class of polyepoxyalkane chemicals with a flexible polyether backbone capped by primary and secondary amines. Due to the ease with which various groups react with the terminal amines of the polyether backbone chain, they have found numerous applications in modern chemical industries, such as ion exchange, lubricant additives, epoxy resin curing agents, plasticizers, and polyurethane (polyurea) spraying, all with good results. Catalyst research has always played a crucial role in the synthesis of polyetheramines. Among the many types of catalysts, nickel-based catalysts have long been a focus of attention. Raney nickel and nickel-based supported catalysts have been applied in actual polyetheramine production processes with some success, but certain problems also exist. For example, the catalysts are prone to deactivation, typically having a lifespan of only about six months. Furthermore, Raney nickel catalysts are prone to flash explosions, posing certain safety hazards if improperly stored.

[0003] CN110964194A discloses a method for preparing and applying a polyetheramine catalyst. The specific steps include: first, preparing potassium-based montmorillonite; then, using an equal-volume impregnation method, loading a metal salt solution containing active components and additives onto a γ-Al₂O₃ support; drying and calcining to obtain a support loaded with metal oxides; subsequently, performing a second impregnation and adding an equal volume of an organic amine solution of potassium-based montmorillonite, followed by drying and calcination; placing the resulting modified support loaded with metal oxides into a rotary furnace and reducing it with hydrogen gas to obtain the polyetheramine catalyst. This catalyst exhibits a certain degree of resistance to hydration; however, during long-term use, the active metal components of the supported catalyst are easily lost, and the content of the main active metal components is limited, meaning that both the reaction activity and lifespan are limited.

[0004] CN113045744A discloses a polyetheramine catalyst and its preparation method. The polyetheramine catalyst is prepared from a skeletal copper catalyst, a palladium salt solution, and deionized water. The skeletal copper catalyst is an aluminum-copper alloy obtained by dissolving metallic aluminum in an alkaline solution. The palladium salt solution is prepared from palladium salt, a complexing agent, a stabilizer, and water. In the preparation process, metallic aluminum in the aluminum-copper alloy is first dissolved in an alkaline solution to obtain the skeletal copper catalyst, which is then washed with deionized water until the pH of the skeletal copper catalyst is neutral. Simultaneously, a mixture of the complexing agent, stabilizer, and water is prepared, and then the palladium salt is added to the mixture and dissolved to form a palladium salt solution. Finally, the prepared skeletal copper catalyst is added to deionized water and stirred to form a suspension. The palladium salt solution is then gradually added dropwise to the suspension, stirred, and reacted. Finally, the mixture is washed with deionized water to obtain the polyetheramine catalyst. The catalyst has certain catalytic activity and selectivity. However, using the precious metal palladium as the active center of the catalyst results in a high cost. Moreover, palladium metal has poor resistance to impurity interference and is easily poisoned, meaning that the catalyst operation is very demanding. At the same time, the preparation process is complicated and not convenient for industrial production. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention provides a polyetheramine catalyst, its preparation method, and its applications. The polyetheramine catalyst provided by this invention has advantages such as high reaction conversion and selectivity, long service life, and simple preparation process.

[0006] The first aspect of the present invention provides a polyetheramine catalyst, wherein the polyetheramine catalyst is a carbon-nitrogen-doped multi-metal catalyst, wherein the multi-metal includes nickel, molybdenum and aluminum.

[0007] Furthermore, in the polyetheramine catalyst, the total content of the multi-metals nickel, molybdenum, and aluminum and the doped carbon and nitrogen is 100% by elemental mass, wherein the nickel content is 80% to 90%, the molybdenum content is 3% to 5%, the aluminum content is 4% to 10%, the carbon content is 1% to 5%, and the nitrogen content is 0.5% to 2.5%.

[0008] Furthermore, in the carbon-nitrogen doping, nitrogen atoms form an NC=N structure with the carbon layer.

[0009] Furthermore, the specific surface area of ​​the polyetheramine catalyst is 50 m². 2 / g~85m 2 / g, pore volume 0.56cm 3 / g~0.79cm 3 / g, with a mesoporous content of 30%–46%.

[0010] Further, preferably, the specific surface area of ​​the polyetheramine catalyst is 60 m². 2 / g~85m 2 / g, pore volume 0.65cm 3 / g~0.79cm 3 / g, with a mesoporous content of 35%–46%.

[0011] Furthermore, the total acidity of the polyetheramine catalyst is 0.21 mmol / g to 0.52 mmol / g, and the ratio of B acid to L acid (B / L) is 2.9 to 6.8.

[0012] Further, preferably, the total acidity of the polyetheramine catalyst is 0.27 mmol / g to 0.43 mmol / g, and the ratio of B acid to L acid (B / L) is 3.5 to 5.7.

[0013] A second aspect of the present invention provides a method for preparing the above-mentioned polyetheramine catalyst, comprising the following steps:

[0014] (1) Weigh out nickel salt, molybdenum salt, amino-functionalized modified aluminum-based hydrated salt and water and mix them to prepare a mixed metal salt solution;

[0015] (2) Add the mixed metal salt solution and precipitant from step (1) dropwise to the alkaline buffer solution, heat to react, and then age.

[0016] (3) The aged material is washed, dried, and calcined in an inert atmosphere to obtain a polyetheramine catalyst.

[0017] Further, the amino-functionalized modified aluminum-based hydrated salt in step (1) is modified by amine-aldehyde condensation of pretreated chitosan and aldehydes on the aluminum-based hydrated salt.

[0018] Furthermore, the method for preparing the pretreated chitosan includes: mixing chitosan powder containing 85% to 95% deacetylation with an aqueous solution of acetic acid with a mass concentration of 1% to 5%, stirring and reacting to obtain the pretreated chitosan.

[0019] Furthermore, in the method for preparing the pretreated chitosan, the stirring reaction is carried out at 200 rpm to 400 rpm and 20°C to 30°C for 8 to 15 hours.

[0020] Furthermore, in the method for preparing the pretreated chitosan, the mass ratio of chitosan to aqueous acetic acid is 1:(75-125); the mass ratio of chitosan to aluminum-based hydrated salt is 1:(0.5-4.5); and the mass ratio of chitosan to aqueous aldehyde solution is 1:(2.5-9.5).

[0021] Furthermore, the amino-functionalized modified aluminum-based hydrated salt is preferably prepared by first mixing and stirring the pretreated chitosan with the aluminum-based hydrated salt to carry out a first reaction, and then adding aldehydes to carry out a second reaction.

[0022] Furthermore, the aldehydes are added in the form of an aqueous aldehyde solution with a mass concentration of 5% to 15%.

[0023] Furthermore, the aldehydes are selected from at least one of glutaraldehyde, glucose diacetaldehyde, and adipaldehyde.

[0024] Furthermore, the conditions for the first reaction are to continuously stir for 1 to 4 hours at 80 rpm to 120 rpm and 20°C to 30°C; the conditions for the second reaction are to stir for 10 to 30 hours at 80 rpm to 120 rpm and 20°C to 30°C.

[0025] Furthermore, after the second reaction is complete, conventional processes in this field, such as filtration, washing, and drying, can be performed.

[0026] Furthermore, the aluminum-based hydrated salt is preferably boehmite monohydrate.

[0027] Furthermore, in step (1), the nickel salt is preferably nickel nitrate hexahydrate.

[0028] Furthermore, in step (1), the molybdenum salt is preferably molybdenum chloride pentahydrate.

[0029] Further, in step (1), the mass ratio of the nickel salt, molybdenum salt, amino-functionalized modified aluminum-based hydrated salt and water is 1:(0.008-0.045):(0.195-0.624):(1-10), preferably 1:(0.014-0.026):(0.286-0.448):(3-6).

[0030] Further, in step (1), the mixture is stirred at a speed of 200 rpm to 400 rpm for 15 min to 25 min.

[0031] Further, in step (2), the precipitant is an ammonia solution, wherein the mass concentration of the ammonia solution is 2.5% to 8.5%, preferably 4.5% to 7.0%.

[0032] Further, in step (2), the alkaline buffer solution includes sodium carbonate, sodium bicarbonate and water; wherein the mass ratio of sodium carbonate, sodium bicarbonate and water is 1:(0.85~1.86):(150~260), preferably 1:(1.17~1.56):(180~220).

[0033] Furthermore, in step (2), the pH range of the alkaline buffer solution is 8 to 11.5, preferably 9 to 10.

[0034] Further, in step (2), the mass ratio of the mixed metal salt solution, precipitant and alkaline buffer solution is 1:(0.65-1.27):(0.25-0.95), preferably 1:(0.85-1.06):(0.38-0.62).

[0035] Furthermore, in step (2), the stirring speed during the dripping stage is 300 rpm to 1000 rpm, preferably 500 rpm to 700 rpm.

[0036] Further, in step (2), the dropping rate is 1g alkaline buffer solution: (0.5mL / min to 10mL / min) mixed metal salt solution and precipitant, preferably 1g alkaline buffer solution: (2mL / min to 6.5mL / min) mixed metal salt solution and precipitant.

[0037] Furthermore, in step (2), the heating reaction time is 10 min to 60 min, preferably 25 min to 40 min.

[0038] Furthermore, in step (2), the temperature of the heating reaction is 90℃~140℃, preferably 105℃~120℃.

[0039] Furthermore, in step (2), the aging time is 0.5h to 6.5h, preferably 2.5h to 4.5h.

[0040] Further, in step (3), the washing and drying are performed using conventional methods in the art. For example, washing is performed by centrifugation, and the product is washed with deionized water until neutral. The drying temperature is 60℃~120℃, preferably 85℃~100℃, and the drying time is 2h~12h, preferably 5h~8h. Preferably, the product is pulverized after drying, and the particle size of the pulverized product is 10 mesh~100 mesh, preferably 40 mesh~60 mesh.

[0041] Further, in step (3), the calcination temperature is 350℃~800℃, preferably 450℃~650℃, and the time is 3h~10h, preferably 5h~7h. The inert atmosphere is an oxygen-free atmosphere, preferably nitrogen and / or helium.

[0042] A third aspect of the present invention provides the application of the above-mentioned polyetheramine catalyst in the catalytic amination reaction of polyether polyols to produce polyetheramines.

[0043] Furthermore, the reaction temperature is 200℃~230℃, the reaction pressure is 4MPa~6MPa, the volume ratio of polyether polyol, liquid ammonia, and hydrogen is 1:(0.75~5.05):(1000~1500), and the volume liquid hourly space velocity of the polyether polyol is 0.05h⁻¹. -1~0.5h -1 .

[0044] Furthermore, the polyetheramine product is a colorless to pale yellow liquid with an APHA value of 6.5 to 9.5, a water content of 0.1 wt% to 0.15 wt%, and a total amine value (mgKOH / g) of 477.8 to 482.6.

[0045] Compared with the prior art, the present invention has the following advantages:

[0046] (1) The polyetheramine catalyst provided by this invention, firstly, the synergistic effect of the metal components molybdenum and nickel is beneficial to increasing the rate of dehydrogenation of the terminal hydroxyl groups of the raw material polyether polyol to generate carbonyl groups, that is, increasing the conversion rate of the polyether polyol raw material, wherein the conversion rate of the polyether polyol can reach 90% to 95%. In addition, the synergistic effect of the metal components aluminum and nickel is also beneficial to suppressing the occurrence of side reactions, that is, increasing the selectivity of the main product primary amine, the primary amine selectivity is 98.7% to 99.6%. Secondly, the polyetheramine catalyst of this invention is nitrogen-carbon doped, wherein the metal components and carbon materials are cross-linked to have a certain mesoporous structure, which is beneficial to the entry of the raw material polyether polyol into the catalyst pores for reaction and the rapid diffusion and outflow of the product polyetheramine. Furthermore, the presence of the carbon layer spatially separates the metal particles, ensuring that the highly active components (nickel content exceeding 80%) are not lost or agglomerated during the reaction, thus improving catalyst stability. Simultaneously, the introduction of nitrogen atoms helps disperse the metal particles, enhancing their interaction with the support. The formation of an NC=N structure between nitrogen atoms and the carbon layer strengthens the interaction between catalyst components. Nitrogen-doped carbon-supported catalysts exhibit higher catalytic activity than catalysts obtained through other methods. Nitrogen doping not only introduces structural defects into the carbon material, altering its morphology, but also changes the electron cloud density of the carbon atoms surrounding the nitrogen atoms, enhancing electron transfer between systems and thus improving the catalyst's performance. The product yield is 70%–80%.

[0047] (2) In the preparation method of this invention, amino-modified aluminum salt is mixed with nickel salt and molybdenum salt. During the preparation of the amino-functionalized modified aluminum-based hydrated salt, amino functional groups and a double-helix structure are simultaneously introduced through the reactant chitosan. After chemical precipitation and calcination, heteroatom nitrogen successfully enters the ternary catalyst containing nickel, molybdenum, and aluminum metal components. The metal elements and the carbon material generated after chitosan calcination are solidified together in a colloidal aggregate form. Because nitrogen atoms are incorporated into the mixed metal colloid, new lattice defects are generated, resulting in a certain number of defect sites with local charges. These defect sites can serve as new reactive centers, promoting the catalytic reaction, reducing acidity, and extending the catalyst's lifespan. Simultaneously, due to the double-helix structure of chitosan, the spatial structure of the mixed metal colloid after chemical precipitation and calcination becomes asymmetrical, which facilitates the rapid diffusion of the larger reaction intermediate, enimine, further reacting to generate polyetheramine. During the calcination process for catalyst preparation, the carbon matrix... 3+ In-situ reduction to elemental Al metal enhances reaction activity. Furthermore, the abundant hydrogen bonds in the chitosan structure ensure that the three metals are tightly bound together in the colloid, resulting in less metal loss and a longer lifespan compared to supported catalysts.

[0048] (3) This invention does not use precious metals as catalyst components, which helps to reduce production costs. Moreover, the preparation process is simple and easy to apply in industrial mass production. Attached Figure Description

[0049] Figure 1 A reaction mechanism diagram for the preparation of polyetheramines by catalytic amination;

[0050] Figure 2 The following are the Fourier transform infrared (FT-IR) spectra of the polyetheramines prepared in Example 1 and Comparative Example 6;

[0051] Figure 3 The X-ray photoelectron spectroscopy (XPS local region) of the catalyst prepared in Example 1. Detailed Implementation

[0052] The following examples further illustrate the preparation method and effects of the polyetheramine catalyst of the present invention. These examples are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following examples.

[0053] Unless otherwise specified, the experimental methods used in the following examples are conventional methods in the art. Unless otherwise specified, the experimental materials used in the following examples were purchased from conventional biochemical reagent stores.

[0054] In this invention, the specific surface area and pore volume of the polyetheramine catalyst were determined using a 3H-2000PM2 specific surface area analyzer manufactured by Beijing Bestech Co., Ltd. Before testing, the samples underwent vacuum degassing at 373K, and nitrogen adsorption-desorption isotherms were measured at 77K. The specific surface area and pore volume of the samples were then analyzed using the BET method.

[0055] Mesopority % = (Mesopore volume / Total pore volume) × 100%,

[0056] In this invention, the chemical composition of the polyetheramine product was analyzed using an FTIR-650S Fourier transform infrared spectrometer manufactured by Tianjin Gangdong Technology Co., Ltd. Before testing, the sample was treated with KBr pellets in a wavenumber range of 500 cm⁻¹. -1 ~4000cm -1 .

[0057] In this invention, the content of each metal in the polyetheramine catalyst was quantitatively analyzed using an XDL 230 X-ray fluorescence spectrometer manufactured by Fischer GmbH, Germany.

[0058] In this invention, a PHI-5000C ESCA X-ray photoelectron spectrometer manufactured by PerkinWlmer, USA, was used to test the catalyst and analyze its surface chemical composition and state. During the experiment, a high voltage of 14.0 kV and a power of 300 W were used. Binding energy correction was performed based on C1s = 286 eV, and peak fitting was performed using XPS Peak 4.1 software.

[0059] In this invention, the acidity and acid content of the samples were tested using an Auto Chem 2920 ammonia temperature-programmed desorption (NH3-TPD) instrument manufactured by Micromeritics, USA. The test procedure was as follows: the samples were pretreated in a helium (He) gas flow (50 mL / min) at 300°C for 2 hours, then cooled to 100°C, and 10% helium was introduced into the atmosphere. The NH3 / He mixed gas (flow rate 50 mL / min) was saturated for 1 h, then the He gas flow (flow rate 50 mL / min) was switched and purged for 1 h to remove the weakly physically adsorbed NH3 on the surface. Finally, the temperature was raised to 600℃ at a rate of 10℃ / min for desorption.

[0060] In this invention, a Matrix-F pyridine infrared spectrometer manufactured by Bruker GmbH, Germany, was used to measure the ratio of Brønsted acid (B) to Lewis acid (L) in the sample. 10 mg of powder sample was pressed into a thin sheet, fixed in the infrared cell, and vacuum-purified for 2 hours. After cooling to room temperature, the spectrum was scanned as background. After pyridine adsorption at room temperature, the temperature was programmed to the measurement temperature (fixed points of 200℃ and 350℃) for vacuum desorption for 0.5 hours, followed by cooling to room temperature. The values ​​of 1700–1400 cm⁻¹ were recorded. -1Infrared spectrum in the wavenumber region. At 1540 cm⁻¹ -1 Peak characterization of Brønsted acid, with 1450 cm⁻¹ -1 Peak characterization of L-acid.

[0061] In this invention, the quality testing standards for polyetheramine products are implemented in accordance with the enterprise standard Q / 0602YMS 001-2019 of Yantai Minsheng Chemical Co., Ltd.

[0062] Example 1

[0063] First, amino-functionalized aluminum-based hydrated salts were prepared: 1 g of chitosan powder with a degree of deacetylation of 90% was weighed and mixed with 100 g of a 3% acetic acid aqueous solution. The mixture was stirred continuously at 300 rpm and 25°C for 10 h to obtain pretreated chitosan. Then, 1.5 g of boehmite monohydrate was added to the pretreated chitosan, and the mixture was stirred continuously at 100 rpm and 25°C for 3 h to obtain a suspension. 4.5 g of a 10% glutaraldehyde aqueous solution was added dropwise to the suspension, and the mixture was stirred continuously at 100 rpm and 25°C for 20 h. The resulting product was then filtered and repeatedly washed with deionized water until neutral. Finally, it was dried in an oven at 75°C for 72 h to obtain amino-functionalized aluminum-based hydrated salts.

[0064] 40g of nickel nitrate hexahydrate, 0.8g of molybdenum chloride pentahydrate, and 14.8g of amino-functionalized aluminum-based hydrated salt were weighed and dissolved in 200g of deionized water at 25℃. The solution was stirred at 300rpm for 20min to obtain a mixed metal salt solution. Also at 25℃, 27% ammonia solution was measured and diluted to 6% to obtain a precipitant. 0.5g of sodium carbonate and 0.63g of sodium bicarbonate were weighed and added to 100g of deionized water, and dissolved by stirring at 300rpm for 20min to obtain an alkaline buffer solution with a pH of 9.5. The stirring speed was increased to 600rpm, and 200g of the mixed metal salt solution and 200g of the precipitant were added dropwise to 100g of the alkaline buffer solution at a rate of 4mL / min. After reacting for 35min, stirring was stopped, and the product was heated to 110℃ and aged for 3.5h. The aged material was centrifuged at 9000 rpm for 6 minutes, then washed with deionized water until neutral, and dried in an oven at 90°C for 7 hours. After drying, it was cooled to 25°C and pulverized to a particle size of 50 mesh. It was then calcined under a nitrogen atmosphere at 550°C for 6 hours to obtain the polyetheramine catalyst.

[0065] X-ray photoelectron spectroscopy (XPS) revealed signal peaks at 286 eV and 400 eV in the XPS half-spectrum (200 eV–600 eV), corresponding to the C1s and N1s orbitals, respectively. The presence of the N1s signal further indicates the incorporation of nitrogen heteroatoms in the catalyst composition. Since no oxygen was detected in the 200 eV–600 eV half-spectrum (oxygen signal peaks typically appear between 500 eV and 600 eV), the high-resolution C1s spectrum was decomposed into two separate peaks at 285.8 eV and 286.4 eV, corresponding to the CC / C=C and NC=N groups, respectively.

[0066] Example 2

[0067] The preparation method of the amino-functionalized modified aluminum-based hydrated salt is the same as in Example 1.

[0068] 40 g of nickel nitrate hexahydrate, 0.56 g of molybdenum chloride pentahydrate, and 11.44 g of amino-functionalized aluminum-based hydrated salt were weighed and dissolved in 120 g of deionized water at 25 °C. The solution was stirred at 200 rpm for 15 min to obtain a mixed metal salt solution. Also at 25 °C, 27% ammonia solution was measured and diluted to 6% to obtain a precipitant. 0.5 g of sodium carbonate and 0.585 g of sodium bicarbonate were weighed and added to 90 g of deionized water, and the solution was stirred at 200 rpm for 15 min to dissolve, resulting in an alkaline buffer solution with a pH of 9.5. The stirring speed was increased to 600 rpm, and 90 g of the mixed metal salt solution and 76.5 g of the precipitant were added dropwise to 34.2 g of alkaline buffer solution at a rate of 4.8 mL / min. After reacting for 25 min, stirring was stopped, and the product was heated to 105 °C and aged for 2.5 h. The aged material was centrifuged at 9000 rpm for 6 minutes, then washed with deionized water until neutral, and dried in an oven at 85°C for 5 hours. After drying, it was cooled to 25°C and pulverized to a particle size of 40 mesh. It was then calcined under a nitrogen atmosphere at 450°C for 5 hours to obtain the polyetheramine catalyst.

[0069] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0070] Example 3

[0071] The preparation method of amino-functionalized modified aluminum-based hydrated salt is the same as in Example 1.

[0072] 40 g of nickel nitrate hexahydrate, 1.04 g of molybdenum chloride pentahydrate, and 17.92 g of amino-functionalized aluminum-based hydrated salt were weighed and dissolved in 240 g of deionized water at 25 °C. The solution was stirred at 400 rpm for 25 min to obtain a mixed metal salt solution. Also at 25 °C, 27% ammonia solution was measured and diluted to 6% to obtain a precipitant. 0.5 g of sodium carbonate and 0.78 g of sodium bicarbonate were weighed and added to 110 g of deionized water, and dissolved by stirring at 400 rpm for 25 min to obtain an alkaline buffer solution with a pH of 9.5. The stirring speed was increased to 600 rpm, and 200 g of the mixed metal salt solution and 200 g of the precipitant were added dropwise to 100 g of alkaline buffer solution at a rate of 8 mL / min. After reacting for 40 min, stirring was stopped, and the product was heated to 120 °C and aged for 4.5 h. The aged material was centrifuged at 9000 rpm for 6 minutes, then washed with deionized water until neutral, and dried in an oven at 100°C for 8 hours. After drying, it was cooled to 25°C and then pulverized to a particle size of 60 mesh. It was then calcined under a nitrogen atmosphere at 650°C for 7 hours to obtain the polyetheramine catalyst.

[0073] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0074] Example 4

[0075] Similar to Example 1, except that the mass of molybdenum chloride pentahydrate, amino-functionalized aluminum-based hydrated salt, and deionized water were increased to 1.4 g, 24.96 g, and 400 g, respectively, while other reaction conditions and material composition remained unchanged, to obtain a polyetheramine catalyst.

[0076] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0077] Example 5

[0078] Similar to Example 1, except that the concentration of diluted ammonia was reduced to 2.5%, while other reaction conditions and material composition remained unchanged, resulting in a polyetheramine catalyst.

[0079] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0080] Example 6

[0081] Similar to Example 1, except that the mass of sodium bicarbonate was reduced to 0.475g, while other reaction conditions and material composition remained unchanged. The resulting alkaline buffer solution had a pH of 8.3, thus yielding the polyetheramine catalyst.

[0082] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0083] Example 7

[0084] Similar to Example 1, except that the mass of the precipitant was reduced to 150g and the mass of the alkaline buffer solution was increased to 170g, while other reaction conditions and material composition remained unchanged, to obtain a polyetheramine catalyst.

[0085] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0086] Example 8

[0087] Similar to Example 1, except that the stirring speed during the dropping stage was increased to 1000 rpm, the dropping rate was reduced to 3.5 mL / min, and the reaction time after the low-valence phase was extended to 60 min, while other reaction conditions and material composition remained unchanged, thus obtaining the polyetheramine catalyst.

[0088] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0089] Example 9

[0090] Similar to Example 1, except that the heating temperature was increased to 140°C and the aging time was reduced to 0.5 h, while other reaction conditions and material composition remained unchanged, resulting in a polyetheramine catalyst.

[0091] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0092] Example 10

[0093] Similar to Example 1, except that the calcination temperature was increased to 650°C and the time was shortened to 3 hours, while other reaction conditions and material composition remained unchanged, resulting in a polyetheramine catalyst.

[0094] As in Example 1, the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0095] Comparative Example 1

[0096] Same as Example 1, except that nickel nitrate hexahydrate is omitted, while other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0097] Comparative Example 2

[0098] Same as Example 1, except that molybdenum chloride pentahydrate is omitted, while other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0099] Comparative Example 3

[0100] Same as Example 1, except that the amino-functionalized aluminum-based hydrated salt is omitted, while other reaction conditions and material composition remain unchanged, resulting in a polyetheramine catalyst.

[0101] Comparative Example 4

[0102] Similar to Example 1, except that the alkaline buffer preparation step is omitted, and the mixed metal salt solution and precipitant are directly mixed, while other reaction conditions and material composition remain unchanged, to obtain the polyetheramine catalyst.

[0103] Comparative Example 5

[0104] Similar to Example 1, except that the method of adding the mixed metal salt solution and precipitant to the alkaline buffer solution was changed to directly pouring them into the alkaline buffer solution, while other reaction conditions and material composition remained unchanged, to obtain the polyetheramine catalyst.

[0105] Comparative Example 6

[0106] Same as Example 1, except that aluminum chloride hexahydrate is used instead of the amino-functionalized aluminum-based hydrated salt, while other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0107] Comparative Example 7

[0108] Same as Example 1, except that diaspore monohydrate is used instead of the amino-functionalized aluminum-based hydrated salt, while other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0109] Comparative Example 8

[0110] Following the method described in CN110964194A, 50 parts of montmorillonite were added to a four-necked flask containing 350 parts of 5% KNO3 solution. The flask was heated in a water bath and stirred at a constant speed for 30 minutes. After filtration, the flask was washed three times with deionized water and then dried in a vacuum drying oven at 110℃ for 4 hours to obtain potassium-based montmorillonite. A mixed metal salt was loaded onto 1000 parts of γ-Al₂O₃ using an equal-volume impregnation method. After impregnation, the flask was dried for 3 hours and then calcined in a muffle furnace for 8 hours to complete the first impregnation. Half the mass of the metal salt solution and 500 parts of dimethylamine solution containing 15 parts of potassium-based montmorillonite were used for the first impregnation and loaded onto the calcined support using an equal-volume impregnation method. After impregnation, the flask was dried for 3 hours and then calcined in a muffle furnace for 8 hours to obtain a metal oxide-modified support. The modified metal oxide support was then placed in a rotary furnace and reduced with hydrogen for 14 hours to obtain a polyetheramine catalyst.

[0111] Comparative Example 9

[0112] Following the method described in CN113045744A, aluminum-copper alloy was first crushed into alloy blocks with a particle size of 1mm to 4mm. 200g of the alloy block was weighed and slowly added in batches to a 20% sodium hydroxide solution for 2 hours of activation to obtain a framework copper catalyst. The framework copper catalyst was then washed with deionized water at 20℃ to 40℃ until pH = 8. Next, 1.7g of dichlorotetraamminepalladium was weighed and dissolved in 10mL of deionized water. 2.3mL of ethylenediamine solution was measured and added dropwise to 10mL of deionized water to prepare a homogeneous solution. The ethylenediamine aqueous solution was added dropwise to the palladium chloride solution, followed by the addition of 11mg of bismuth chloride to dissolve. The solution was then diluted to a 200mL volumetric flask to form a 3mgPd / mL palladium salt solution. 30mL of the framework copper catalyst was then added to 50mL of deionized water and added dropwise to 10mL of the palladium salt solution. After reacting for 2 hours, the solution was filtered to obtain a polyetheramine catalyst.

[0113] Test Example 1

[0114] The physicochemical properties of the polyetheramine catalysts in Examples 1-10 and Comparative Examples 1-9 were determined, and the specific results are shown in Table 1.

[0115] Table 1. Performance of the polyetheramine catalysts prepared in the examples and comparative examples.

[0116]

[0117]

[0118] From Table 1 and Figure 1 It can be seen that the polyetheramine catalyst prepared by the method of the present invention has good physicochemical properties and a high nickel content. The BET specific surface area, pore volume, and mesoporosity of the sample in Example 1 reached 85 m². 2 / g, 0.79cm 3 The content of nickel metal reaches 87%, the total acidity is 0.35 mmol / g, and the ratio of Brønsted acid to Lewis acid (B / L) is 4.3.

[0119] In the comparative samples, the BET specific surface area, pore volume, and mesoporosity were generally lower than 55 m². 2 / g, 0.45cm 3 The nickel content is less than 85%, the total acidity is less than 0.27 mmol / g, and the B / L is not within the preferred range.

[0120] Test Example 2

[0121] The effects of polyether polyol catalytic amination reaction and product quality in Examples 1, 2, and Comparative Examples were determined. The specific results are shown in Tables 2 and 3.

[0122] Table 2 shows the effect of polyether polyol catalytic amination reaction in the examples and comparative examples.

[0123]

[0124]

[0125] Table 3 Product quality of polyetheramine in Examples and Comparative Examples

[0126]

[0127] In Test Example 2, polypropylene glycol with an average molecular weight of 230 was used as the raw material. Before use, the catalyst underwent reduction activation treatment in a hydrogen environment (reduction at 200℃ for 3 hours, reduction at 400℃ for 5 hours, hydrogen flow rate 100 mL / min). The catalyst loading was 50 mL, the reaction temperature was 210℃, the reaction pressure was 5 MPa, the ratio of polypropylene glycol volume, liquid ammonia volume, and hydrogen volume was 1:3:1200, and the liquid hourly space velocity (LHSV) of polypropylene glycol was 0.25 h⁻¹. -1 .

[0128] As shown in Table 2, using the polyetheramine catalyst prepared in this invention for the catalytic amination reaction of polyether polyols can achieve high feed conversion rates, primary amine selectivity, and product yields. The feed conversion rate, primary amine selectivity, and product yield of the sample in Example 1 reached 95%, 99.6%, and 80%, respectively, while the feed conversion rate, primary amine selectivity, and product yield of the sample in Comparative Example 6 were only 69.2%, 77.8%, and 58.5%, respectively. Figure 2 Infrared spectroscopy analysis shows that at 3250 cm⁻¹ -1 ~3500cm -1 In the meantime, the OH stretching vibration peak in the sample of Example 1 basically disappeared, and the primary amine double-peak structure replaced it, indicating that the conversion rate of the raw material polyether was high and the selectivity of the obtained product primary amine was high during the polyether catalytic amination reaction using the catalyst of Example 1. Conversely, in Comparative Example 6, although the primary amine double-peak structure appeared, there were still obvious OH stretching vibration peak structural units, proving that its raw material conversion rate was limited.

[0129] As shown in Table 3, during the product quality verification process based on the enterprise standard Q / 0602YMS 001-2019 of Yantai Minsheng Chemical Co., Ltd., it was found that all technical indicators of the example samples were significantly better than those of the comparative sample.

Claims

1. A polyether amine catalyst, the polyether amine catalyst is a carbon-nitrogen doped multi-metal catalyst, wherein the multi-metal comprises nickel, molybdenum and aluminum; In the polyether amine catalyst, the total content of the multi-metallic nickel, molybdenum and aluminum and the doped carbon and nitrogen is 100% in terms of element mass, wherein, The content of nickel is 80%-90%, the content of molybdenum is 3%-5%, the content of aluminum is 4%-10%, the content of carbon is 1%-5%, and the content of nitrogen is 0.5%-2.5%; The preparation method of the polyether amine catalyst comprises the following steps: (1) weighing nickel salt, molybdenum salt, amino-functionalized aluminum-based hydrated salt and water to prepare a mixed metal salt solution; (2) adding the mixed metal salt solution and a precipitant of step (1) to an alkaline buffer solution, heating and reacting, and then aging; (3) washing, drying and calcining the aged material in an inert atmosphere to obtain the polyether amine catalyst; In step (1), the amino-functionalized aluminum-based hydrated salt is modified by amine aldehyde condensation of aluminum-based hydrated salt with pretreated chitosan and aldehyde; The preparation method of the pretreated chitosan comprises mixing chitosan powder with a deacetylation degree of 85%-95% and an aqueous acetic acid solution with a mass concentration of 1%-5%, and stirring to obtain the pretreated chitosan; In step (2), the alkaline buffer solution comprises sodium carbonate, sodium bicarbonate and water; The mass ratio of sodium carbonate, sodium bicarbonate and water is 1: (0.85-1.86) : (150-260); In step (2), the dropping speed is 1 g of alkaline buffer solution: (0.5 mL / min-10 mL / min) mixed metal salt solution and precipitant.

2. The polyetheramine catalyst of claim 1, wherein, In the carbon-nitrogen doping, nitrogen atoms form N-C=N structure with carbon layers.

3. The polyetheramine catalyst of claim 1, wherein, The specific surface area of the polyetheramine catalyst is 50 m 2 / g~85 m 2 / g, the pore volume is 0.56 cm 3 / g~0.79 cm 3 / g, the mesopore ratio is 30%~46%.

4. The polyetheramine catalyst of claim 1, wherein, The total acid amount of the polyether amine catalyst is 0.21 mmol / g-0.52 mmol / g, and the ratio of B acid amount to L acid amount (B / L) is 2.9-6.

8. 5.The preparation method of the polyether amine catalyst according to any one of claims 1-4, comprising the following steps: (1) weighing nickel salt, molybdenum salt, amino-functionalized aluminum-based hydrated salt and water to prepare a mixed metal salt solution; (2) adding the mixed metal salt solution and a precipitant of step (1) to an alkaline buffer solution, heating and reacting, and then aging; (3) washing, drying and calcining the aged material in an inert atmosphere to obtain the polyether amine catalyst; 6. The production method according to claim 5, wherein In step (1), the amino-functionalized aluminum-based hydrated salt is modified by amine aldehyde condensation of aluminum-based hydrated salt with pretreated chitosan and aldehyde; 7. The preparation method according to claim 5, characterized in that, In step (1), the mass ratio of the nickel salt, molybdenum salt, amino-functionalized aluminum-based hydrated salt and water is 1: (0.008-0.045) : (0.195-0.624) : (1-10).

8. The preparation method according to claim 5, characterized in that, In step (2), the mass ratio of the mixed metal salt solution, precipitant and alkaline buffer solution is 1: (0.65-1.27) : (0.25-0.95).

9. The preparation method according to claim 5, characterized in that, In step (2), the heating reaction time is 10 min-60 min, and the heating reaction temperature is 90℃-140℃; The aging time is 0.5 h-6.5 h.

10. The method of claim 5, wherein, In step (3), the calcination temperature is 350-800°C, and the time is 3-10 hours; the inert atmosphere is an atmosphere free of oxygen.

11. The method of claim 5, wherein, In step (3), the inert atmosphere is nitrogen or / and helium.

12. Use of the polyetheramine catalyst according to any one of claims 1 to 4 for the catalytic amination reaction of a polyether polyol to produce a polyetheramine.

13. Use according to claim 12, characterized in that, The reaction temperature is 200-230°C, the reaction pressure is 4-6 MPa, the volume ratio of polyether polyol, liquid ammonia and hydrogen is 1:(0.75-5.05):(1000-1500), the volume liquid hourly space velocity of polyether polyol is 0.05-0.5 h -1 -0.5 h -1 .

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