Polyether amine catalyst as well as preparation method and application thereof

Abstract

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

Description

Technical Field

[0001] The invention belongs to the technical field of polyetheramines, and in particular relates to a polyetheramine catalyst and a preparation method and application thereof. Background Art

[0002] Polyetheramines, also known as amino-terminated polyethers, are a class of polyalkylene oxide chemicals with a soft polyether skeleton and terminated by primary and secondary amino groups. Since various groups are easy to react with the terminal amino groups of the polyether skeleton chain, they have many application opportunities in the modern chemical industry, such as ion exchange, lubricant additives, epoxy resin curing agents, plasticizers and polyurethane (polyurea) spraying, all of which have achieved good results. The research on catalysts has always played a vital role in the synthesis process of polyetheramines. Among the many types of catalysts, nickel-based catalysts have long been of concern. Among them, Raney nickel and nickel-based supported catalysts have been used in the actual production process of polyetheramines and have achieved certain results, but there are also certain problems. For example, the catalyst is easy to deactivate, and its service life is usually only about half a year. In addition, Raney nickel catalysts are prone to flash explosions, and there are certain safety hazards if they are not stored properly.

[0003] CN110964194A discloses a preparation method and application method of a polyetheramine catalyst. The method specifically comprises the following steps: firstly preparing potassium-based montmorillonite, then using an equal volume impregnation method to load a metal salt solution containing active components and additives onto γ-Al 2 O 3 The carrier is dried and calcined to obtain a carrier loaded with metal oxides; then, it is impregnated twice, and an equal amount of potassium-montmorillonite organic amine solution is added, and then dried and calcined; the obtained modified carrier loaded with metal oxides is placed in a rotary furnace, and hydrogen is introduced for reduction to obtain a polyetheramine catalyst. The catalyst has a certain anti-hydration ability, but the active metal components of the supported catalyst are easily lost during long-term use, and the content of the main active metal components is limited, that is, the reaction activity and life are limited.

[0004] CN113045744A discloses a polyetheramine catalyst and a preparation method. The polyetheramine catalyst is prepared from a skeleton copper catalyst, a palladium salt solution and deionized water; wherein the skeleton copper catalyst is an aluminum-copper alloy obtained by dissolving the metal aluminum in the alloy with an alkaline solution, and the palladium salt solution is made of palladium salt, a complexing agent, a stabilizer and water. During the preparation, the metal aluminum in the aluminum-copper alloy is first dissolved with an alkaline solution to obtain a skeleton copper catalyst, and then washed with deionized water until the pH value of the skeleton copper catalyst is neutral; at the same time, the complexing agent, the stabilizer and water are configured into a mixed solution, and then the palladium salt is added to the mixed solution, dissolved to prepare a palladium salt solution, and finally the prepared skeleton copper catalyst is added to the deionized water, stirred to form a suspension solution, and then the palladium salt solution is gradually added dropwise to the suspension solution, stirred, reacted, and finally washed with deionized water to obtain the polyetheramine catalyst. The catalyst has certain catalytic activity and selectivity. However, the use of precious metal palladium as the active center of the catalyst has a high price cost. In addition, palladium metal has poor resistance to interference from impurities and is easily poisoned, that is, the catalyst operation is highly demanding. At the same time, the preparation process is cumbersome and not convenient for industrial production. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, the present invention provides a polyetheramine catalyst and a preparation method and application thereof. The polyetheramine catalyst provided by the present invention has the advantages of high reaction conversion rate and selectivity, long service life and simple preparation process.

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

[0007] Furthermore, in the polyetheramine catalyst, the total content of the multi-metal nickel, molybdenum and aluminum and the doped carbon and nitrogen is 100% by element 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, a NC=N structure is formed between nitrogen atoms and carbon layers.

[0009] Furthermore, the specific surface area of ​​the polyetheramine catalyst is 50m 2 / g~85m 2 / g, pore volume is 0.56cm 3 / g~0.79cm 3 / g, and the mesoporosity is 30% to 46%.

[0010] Furthermore, preferably, the specific surface area of ​​the polyetheramine catalyst is 60 m 2 / g~85m 2 / g, pore volume is 0.65cm 3 / g~0.79cm 3 / g, and the mesoporosity is 35% to 46%.

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

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

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

[0014] (1) weighing a nickel salt, a molybdenum salt, an amino-functionalized aluminum-based hydrated salt and mixing them with water to prepare a mixed metal salt solution;

[0015] (2) adding the mixed metal salt solution and the precipitant of step (1) dropwise to an alkaline buffer solution, heating for reaction, and then aging;

[0016] (3) Washing and drying the aged material, and calcining it in an inert atmosphere to obtain a polyetheramine catalyst.

[0017] Furthermore, the amino-functionalized aluminum-based hydrated salt described in step (1) is prepared by subjecting the aluminum-based hydrated salt to amine-aldehyde condensation modification using pretreated chitosan and aldehydes.

[0018] Furthermore, the method for preparing the pretreated chitosan comprises: mixing chitosan powder with a deacetylation degree of 85% to 95% with an acetic acid aqueous solution 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 h to 15 h.

[0020] Furthermore, in the method for preparing the pretreated chitosan, the mass ratio of chitosan to acetic acid aqueous solution 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 aldehyde aqueous solution is 1:(2.5-9.5).

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

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

[0023] Furthermore, the aldehyde is selected from at least one of glutaraldehyde, glucose diacetaldehyde and adipic acid dialdehyde.

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

[0025] Furthermore, after the second reaction is completed, conventional filtration, washing and drying in the art may be performed.

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

[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] Furthermore, 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), preferably 1:(0.014-0.026):(0.286-0.448):(3-6).

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

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

[0032] Furthermore, in step (2), the alkaline buffer comprises 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 value of the alkaline buffer solution is in the range of 8 to 11.5, preferably 9 to 10.

[0034] Furthermore, in step (2), the mass ratio of the mixed metal salt solution, the precipitant and the 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 dropwise addition is 300 rpm to 1000 rpm, preferably 500 rpm to 700 rpm.

[0036] Furthermore, in step (2), the dropping speed is 1g alkaline buffer: (0.5mL / min~10mL / min) mixed metal salt solution and precipitant, preferably 1g alkaline buffer: (2mL / min~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°C to 140°C, preferably 105°C to 120°C.

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

[0040] Furthermore, in step (3), the washing and drying are carried out by conventional methods in the art. For example, the washing is carried out by centrifugation, and the mixture is washed with deionized water until neutral. The drying temperature is 60°C to 120°C, preferably 85°C to 100°C, and the drying time is 2h to 12h, preferably 5h to 8h. Preferably, the obtained product is pulverized after drying, and the particle size of the obtained product after the pulverization is 10 mesh to 100 mesh, preferably 40 mesh to 60 mesh.

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

[0042] The third aspect of the present invention provides a use of the above-mentioned polyetheramine catalyst in the catalytic amination reaction of polyether polyol to prepare polyetheramine.

[0043] Furthermore, the reaction temperature is 200°C to 230°C, the reaction pressure is 4MPa to 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 -1~0.5h -1 .

[0044] Furthermore, the polyetheramine product is a colorless to light yellow liquid, with a color value (APHA) 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 the present invention, firstly, the metal components molybdenum and nickel work synergistically, which is conducive to increasing the rate of dehydrogenation of terminal hydroxyl groups of raw material polyether polyol to generate carbonyl groups, that is, increasing the conversion rate of polyether polyol raw materials, wherein the conversion rate of polyether polyol can reach 90% to 95%. In addition, the metal components aluminum and nickel work synergistically, which is also conducive to inhibiting the occurrence of side reactions, that is, increasing the selectivity of the main product primary amine, and the primary amine selectivity is 98.7% to 99.6%. Secondly, the polyetheramine catalyst of the present invention is nitrogen-carbon doped, wherein the metal components and carbon materials are cross-linked with each other to have a certain mesoporous structure, which is conducive to the raw material polyether polyol entering the catalyst pores for reaction and the product polyetheramine quickly diffusing out. Moreover, the presence of the carbon layer spatially separates the metal particles from each other, ensuring the presence of highly active components (nickel content reaches more than 80%), preventing them from being lost and agglomerated during the reaction, and improving the stability of the catalyst; at the same time, the introduction of nitrogen atoms also helps to disperse the metal particles and enhance the interaction between them and the carrier. The NC=N structure is formed between the nitrogen atoms and the carbon layer, which enhances the strong interaction between the catalyst components. The nitrogen-doped carbon carrier catalyst has higher catalytic activity than the catalyst obtained by other methods. The doping of nitrogen elements not only causes structural defects in the carbon material and modulates its morphology; it also changes the electron cloud density of the carbon atoms around the nitrogen atoms, enhances the electron transfer ability between the systems, and thereby improves the catalytic performance of the catalyst. The product yield is 70% to 80%.

[0047] (2) In the preparation method of the present invention, an amino-modified aluminum salt is mixed with a nickel salt and a molybdenum salt, wherein in the stage of preparing the amino-functionalized modified aluminum-based hydrated salt, the amino functional group and the double helix structure are simultaneously introduced through the reaction monomer chitosan, and after chemical precipitation and calcination treatment, the heteroatom nitrogen successfully enters the ternary catalyst containing nickel, molybdenum and aluminum metal components, and the metal elements and the carbon material generated after the chitosan is calcined are solidified together in the form of colloidal aggregation. Since new lattice defects are generated during the process of incorporating nitrogen atoms into the mixed metal colloid, a certain number of defect sites with local charges are generated. These defect sites can serve as new reaction active centers, promote the catalytic reaction and reduce the amount of acid, thereby extending the service life of the catalyst. At the same time, due to the double helix structure of chitosan, the spatial structure of the mixed metal colloid after chemical precipitation and calcination becomes an asymmetric state, which is conducive to the rapid diffusion of the larger reaction intermediate ethyleneimine, and further reaction to generate polyetheramine. During the calcination process to prepare the catalyst, the carbon matrix will Al 3+ In-situ reduction to Al metal element is beneficial to enhance the reaction activity. In addition, the rich hydrogen bond structure in the chitosan structure also makes the three metals tightly combined in the colloid. Compared with the supported catalyst, the metal component is not easy to lose and has a longer service life.

[0048] (3) The present invention does not use precious metals as catalyst components, which is beneficial to reducing production costs, and the preparation process is simple, which is convenient for industrial mass production and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 The reaction mechanism diagram for preparing polyetheramines by catalytic amination;

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

[0051] Figure 3 This is the X-ray photoelectron spectroscopy spectrum (XPS local area) of the catalyst prepared in Example 1. DETAILED DESCRIPTION

[0052] The following examples further illustrate the preparation method and effect of the polyetheramine catalyst of the present invention. The examples are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following examples.

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

[0054] In the present invention, the specific surface area and pore volume of the polyetheramine catalyst are measured using a 3H-2000PM2 specific surface tester produced by Beijing Bester Co., Ltd. Before the test, the sample is subjected to a vacuum degassing treatment at 373K, the nitrogen adsorption-desorption isotherm is tested at 77K, and the specific surface area and pore volume of the sample are analyzed by the BET method.

[0055] Mesoporosity % = (mesopore volume / total pore volume) × 100%,

[0056] In the present invention, the chemical composition of the product polyetheramine was analyzed by using the FTIR-650S Fourier transform infrared spectrometer produced by Tianjin Gangdong Technology Co., Ltd. Before the test, the sample was treated with KBr pellets with a wave number range of 500 cm -1 ~4000cm -1 .

[0057] In the present invention, the XDL 230 X-ray fluorescence spectrometer produced by Fischer Company of Germany is used to quantitatively analyze the content of each metal in the polyetheramine catalyst.

[0058] In the present invention, the catalyst was tested by using a PHI-5000C ESCA X-ray photoelectron spectrometer produced by PerkinWlmer, USA, to analyze the surface chemical composition and state of the catalyst. During the experiment, the high voltage was 14.0 kV, the power was 300 W, the binding energy correction was performed based on C1s = 286 eV, and the XPS Peak4.1 software was used for peak fitting.

[0059] In the present invention, the Auto Chem 2920 ammonia programmed temperature desorption (NH 3 -TPD) instrument to test the acidity and acid content of the sample. Test steps: The sample was pretreated at 300°C for 2h in a helium (He) gas flow (50mL / min), then cooled to 100°C and passed 10% NH 3 / He mixed gas (flow rate 50mL / min) for 1h until saturation, switch to He gas flow (flow rate 50mL / min) to purge for 1h to remove the weakly physically adsorbed NH 3 , and finally the temperature was raised to 600 °C at a heating rate of 10 °C / min before desorption.

[0060] In the present invention, the Matrix-F pyridine infrared spectrometer produced by Bruker Company of Germany is used to measure the ratio of B acid and L acid in the sample. 10 mg of powder sample is pressed into a thin sheet, fixed in an infrared cell, vacuum purified for 2 hours, cooled to room temperature, and the spectrum is scanned as the background. After pyridine is adsorbed at room temperature, the temperature is raised to the measurement temperature (the fixed point temperatures are 200°C and 350°C, respectively) for vacuum desorption for 0.5 hours, and then cooled to room temperature, and the 1700-1400 cm -1 Infrared spectrum in the wavenumber region. At 1540cm -1 The peak characterizing B acid is 1450cm -1 The peak represents L acid.

[0061] In the present invention, the quality inspection standard of the polyetheramine product is implemented according to the enterprise standard Q / 0602YMS 001-2019 of Yantai Minsheng Chemicals Co., Ltd.

[0062] Example 1

[0063] First, prepare the amino-functionalized aluminum-based hydrated salt: weigh 1g of chitosan powder with a deacetylation degree of 90% and mix it with 100g of acetic acid aqueous solution with a mass concentration of 3%, and stir it continuously at 300rpm and 25°C for 10h to obtain the pretreated chitosan. Then add 1.5g of boehmite to the pretreated chitosan, and continue to stir and react for 3h at 100rpm and 25°C to obtain a suspension. Add 4.5g of glutaraldehyde aqueous solution with a mass concentration of 10% to the suspension, and continue to stir and react for 20h at 100rpm and 25°C. Then filter the resultant, rinse it repeatedly with deionized water until it is neutral, and finally dry it in an oven at 75°C for 72h to obtain the amino-functionalized aluminum-based hydrated salt.

[0064] Weigh 40g nickel nitrate hexahydrate, 0.8g molybdenum chloride pentahydrate and 14.8g amino-functionalized aluminum-based hydrated salt respectively, dissolve in 200g deionized water at 25°C, and stir at 300rpm for 20min to obtain a mixed metal salt solution. Also at 25°C, measure ammonia water with a mass concentration of 27% and dilute it to 6% to obtain a precipitant. Measure 0.5g sodium carbonate and 0.63g sodium bicarbonate respectively, add 100g deionized water, and stir at 300rpm for 20min to dissolve to obtain an alkaline buffer solution with a pH value of 9.5. Increase the stirring speed to 600rpm, add 200g mixed metal salt solution and 200g precipitant to 100g alkaline buffer solution at a rate of 4mL / min, stop stirring after 35min of reaction, heat the product to 110°C, and age for 3.5h. The aged material was centrifuged at a speed of 9000 rpm and a time of 6 minutes, then washed with deionized water until neutral, and then dried in an oven at 90°C for 7 hours. After drying, it was aired to 25°C and the obtained material was crushed. The particle size of the obtained material after the crushing was 50 mesh. Then, it was calcined in a nitrogen atmosphere at a temperature of 550°C and a time of 6 hours to obtain a polyetheramine catalyst.

[0065] It can be seen from X-ray photoelectron spectroscopy (XPS) that in the XPS half-spectrum (200eV-600eV), the signal peaks at 286eV and 400eV correspond to C1s and N1s orbitals, respectively. The appearance of the N 1s signal further indicates the incorporation of nitrogen atoms in the catalyst component. Since the presence of oxygen elements is not detected in the 200eV-600eV half-spectrum (usually, the signal peak of oxygen elements appears between 500eV and 600eV), the high-resolution spectrum of C1s is decomposed into two separate peaks of 285.8eV and 286.4eV, corresponding to CC / C=C and NC=N groups, respectively.

[0066] Example 2

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

[0068] Weigh 40g nickel nitrate hexahydrate, 0.56g molybdenum chloride pentahydrate and 11.44g amino-functionalized aluminum-based hydrated salt respectively, dissolve them in 120g deionized water at 25°C, and stir at 200rpm for 15min to obtain a mixed metal salt solution. Also at 25°C, measure ammonia water with a mass concentration of 27% and dilute it to 6% to obtain a precipitant. Measure 0.5g sodium carbonate and 0.585g sodium bicarbonate respectively, add 90g deionized water, and stir at 200rpm for 15min to dissolve to obtain an alkaline buffer solution with a pH value of 9.5. Increase the stirring speed to 600rpm, add 90g mixed metal salt solution and 76.5g precipitant to 34.2g alkaline buffer solution at a rate of 4.8mL / min, stop stirring after 25min of reaction, heat the product to 105°C, and age it for 2.5h. The aged material was centrifuged at a speed of 9000 rpm and a time of 6 minutes, then washed with deionized water until neutral, and then dried in an oven at 85°C for 5 hours. After drying, it was aired to 25°C and the obtained material was crushed. The particle size of the obtained material after the crushing was 40 meshes. Then, it was calcined in a nitrogen atmosphere at a temperature of 450°C and a time of 5 hours to obtain a polyetheramine catalyst.

[0069] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0070] Example 3

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

[0072] Weigh 40g nickel nitrate hexahydrate, 1.04g molybdenum chloride pentahydrate and 17.92g amino-functionalized aluminum-based hydrated salt respectively, dissolve in 240g deionized water at 25°C, and stir at 400rpm for 25min to obtain a mixed metal salt solution. Also at 25°C, measure ammonia water with a mass concentration of 27% and dilute it to 6% to obtain a precipitant. Measure 0.5g sodium carbonate and 0.78g sodium bicarbonate respectively, add 110g deionized water, and stir at 400rpm for 25min to dissolve to obtain an alkaline buffer solution with a pH value of 9.5. Increase the stirring speed to 600rpm, add 200g mixed metal salt solution and 200g precipitant to 100g alkaline buffer solution at a rate of 8mL / min, stop stirring after 40min of reaction, heat the product to 120°C, and age for 4.5h. The aged material was centrifuged at a speed of 9000 rpm and a time of 6 minutes, then washed with deionized water until neutral, and then dried in an oven at 100°C for 8 hours. After drying, it was air-dried to 25°C and the obtained material was crushed. The particle size of the obtained material after crushing was 60 meshes. Then, it was calcined in a nitrogen atmosphere at a temperature of 650°C and a time of 7 hours to obtain a polyetheramine catalyst.

[0073] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0074] Example 4

[0075] The same as Example 1, except that the masses of molybdenum chloride pentahydrate, amino-functionalized aluminum-based hydrated salt and deionized water are increased to 1.4 g, 24.96 g and 400 g respectively, and other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0076] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0077] Example 5

[0078] The same as Example 1, except that the concentration of the diluted ammonia water is reduced to 2.5%, and other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0079] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0080] Example 6

[0081] The same as Example 1, except that the mass of sodium bicarbonate is reduced to 0.475 g, and other reaction conditions and material composition remain unchanged. At this time, the pH value of the obtained alkaline buffer solution is 8.3, and then a polyetheramine catalyst is obtained.

[0082] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0083] Example 7

[0084] The same as Example 1, except that the mass of the precipitant is reduced to 150 g, the mass of the alkaline buffer is increased to 170 g, and other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0085] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0086] Example 8

[0087] The same as Example 1, except that the stirring speed in the dropping stage is increased to 1000 rpm, the dropping speed is reduced to 3.5 mL / min, the reaction time after the end of the low-cost is extended to 60 min, and other reaction conditions and material composition remain unchanged to obtain a polyetheramine catalyst.

[0088] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0089] Example 9

[0090] The same as Example 1, except that the heating temperature is increased to 140° C., the aging time is reduced to 0.5 h, and other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0091] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0092] Example 10

[0093] The same as Example 1, except that the calcination temperature is increased to 650° C., the calcination time is shortened to 3 h, and other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0094] The XPS characterization is the same as that in Example 1, and the polyetheramine catalyst contains CC / C=C and NC=N groups.

[0095] Comparative Example 1

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

[0097] Comparative Example 2

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

[0099] Comparative Example 3

[0100] The same as Example 1, except that the amino-functionalized aluminum-based hydrated salt is omitted, and other reaction conditions and material composition remain unchanged to obtain a polyetheramine catalyst.

[0101] Comparative Example 4

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

[0103] Comparative Example 5

[0104] The same as Example 1, except that the method of adding the mixed metal salt solution and the precipitant dropwise into the alkaline buffer solution is changed to directly pouring into the alkaline buffer solution, and other reaction conditions and material composition remain unchanged, to obtain a polyetheramine catalyst.

[0105] Comparative Example 6

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

[0107] Comparative Example 7

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

[0109] Comparative Example 8

[0110] According to the method described in CN110964194A, 50 parts of montmorillonite were added to 350 parts of 5% KNO 3 The solution was placed in a four-necked flask, heated in a water bath, stirred at a constant speed for 30 minutes, filtered, washed three times with deionized water, and dried in a vacuum oven at 110°C for 4 hours to obtain potassium-based montmorillonite. The mixed metal salt was loaded onto 1000 parts of γ-Al using an equal volume impregnation method. 2 O 3 After the impregnation is completed, it is dried for 3 hours, and then placed in a muffle furnace for calcination 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 are used for the first impregnation, and loaded onto the carrier after the first calcination by an equal volume impregnation method. After the impregnation is completed, it is dried for 3 hours, and then placed in a muffle furnace for calcination for 8 hours to obtain a modified carrier of metal oxide. The modified carrier of the above metal oxide is then placed in a rotary furnace and reduced with hydrogen for 14 hours to obtain a polyetheramine catalyst.

[0111] Comparative Example 9

[0112] According to the method described in CN113045744A, the aluminum-copper alloy is first crushed into alloy blocks with a particle size of 1mm to 4mm, and then 200g of the alloy blocks are weighed and slowly added to a 20% sodium hydroxide solution in batches, activated for 2h to obtain a skeleton copper catalyst; then the skeleton copper catalyst is washed with deionized water at 20℃ to 40℃ until pH = 8. Then 1.7g of dichlorotetraamminepalladium is weighed, 10mL of deionized water is added and stirred to dissolve, 2.3mL of ethylenediamine solution is measured and added dropwise to 10mL of deionized water to form a uniform solution; the ethylenediamine aqueous solution is added dropwise to the palladium chloride solution, and 11mg of bismuth chloride is added to dissolve, and the solution is fixed to a 200mL volumetric flask to form a 3mgPd / mL palladium salt solution. Then 30mL of the skeleton copper catalyst is measured and added to 50mL of deionized water, and then added dropwise to 10mL of palladium salt solution. After reacting for 2h, the solution is filtered to obtain a polyetheramine catalyst.

[0113] Test Example 1

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

[0115] Table 1 Performance of polyetheramine catalysts prepared in 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 physical and chemical properties and a high nickel content. The BET specific surface area, pore volume and mesoporosity of the sample in Example 1 are 85 m 2 / g, 0.79cm 3 / g and 46%, its nickel metal content reaches 87%, the total acid amount is 0.35mmol / g, and the ratio of the B acid amount to the L acid amount (B / L) is 4.3.

[0119] In the comparative samples, the BET specific surface area, pore volume and mesoporosity are generally lower than 55 m 2 / g, 0.45cm 3 / g and 30%, its nickel metal content is also lower than 85%, the total acid content is lower than 0.27mmol / g, and B / L is also not in the preferred range.

[0120] Test Example 2

[0121] The catalytic amination reaction effect and product quality of the polyether polyols in Example 1, Example 2 and Comparative Example were measured. The specific results are shown in Table 2 and Table 3.

[0122] Table 2 Effect of polyether polyol catalyzed amination reaction in Examples and Comparative Examples

[0123]

[0124]

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

[0126]

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

[0128] It can be seen from Table 2 that the use of the polyetheramine catalyst prepared by the present invention to carry out the catalytic amination reaction of polyether polyols can obtain higher raw material conversion rate, primary amine selectivity and product yield. The raw material conversion rate, primary amine selectivity and product yield of the sample of Example 1 reached 95%, 99.6% and 80% respectively, while the raw material conversion rate, primary amine selectivity and product yield of the sample of Comparative Example 6 were only 69.2%, 77.8% and 58.5%. Figure 2 Infrared spectrum analysis shows that at 3250cm -1 ~3500cm -1 , the OH stretching vibration peak in the sample of Example 1 basically disappears, and is replaced by a primary amine double peak structure, indicating that in the process of polyether catalytic amination reaction using the catalyst of Example 1, the conversion rate of the raw material polyether is high, and the selectivity of the obtained product primary amine is high; on the contrary, in Comparative Example 6, although the primary amine double peak structure appears, there is still an obvious OH stretching vibration peak structural unit, proving that its raw material conversion rate is limited.

[0129] It can be seen from Table 3 that in the process of product quality verification according to the enterprise standard Q / 0602YMS 001-2019 of Yantai Minsheng Chemicals Co., Ltd., it was found that the various technical indicators of the embodiment samples were significantly better than those of the comparative example samples.

Claims

1. A polyetheramine catalyst, which is a carbon-nitrogen doped multi-metal catalyst, wherein the multi-metal comprises nickel, molybdenum and aluminum.

2. The polyetheramine catalyst according to claim 1, characterized in that In the polyetheramine catalyst, the total content of multi-metal nickel, molybdenum and aluminum and doped carbon and nitrogen is 100% by element weight, 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%.

3. The polyetheramine catalyst according to claim 1, characterized in that In the carbon-nitrogen doping, a NC=N structure is formed between nitrogen atoms and carbon layers.

4. The polyetheramine catalyst according to claim 1, characterized in that The specific surface area of ​​the polyetheramine catalyst is 50m 2 / g~85m 2 / g, pore volume is 0.56cm 3 / g~0.79cm 3 / g, and the mesoporosity is 30% to 46%.

5. The polyetheramine catalyst according to claim 1, characterized in that The total acid content of the polyetheramine catalyst is 0.21 mmol / g to 0.52 mmol / g, and the ratio of the acid content of B acid to the acid content of L acid (B / L) is 2.9 to 6.

8.

6. The method for preparing the polyetheramine catalyst according to any one of claims 1 to 5, comprising the following steps: (1) weighing a nickel salt, a molybdenum salt, an amino-functionalized aluminum-based hydrated salt and mixing them with water to prepare a mixed metal salt solution; (2) adding the mixed metal salt solution and the precipitant of step (1) dropwise to an alkaline buffer solution, heating for reaction, and then aging; (3) Washing and drying the aged material, and calcining it in an inert atmosphere to obtain a polyetheramine catalyst.

7. The preparation method according to claim 6, characterized in that: The amino-functionalized aluminum-based hydrated salt described in step (1) is prepared by using pretreated chitosan and aldehydes to perform amine-aldehyde condensation modification on the aluminum-based hydrated salt.

8. The preparation method according to claim 6, 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).

9. The preparation method according to claim 6, characterized in that: In step (2), the mass ratio of the mixed metal salt solution, the precipitant and the alkaline buffer solution is 1:(0.65-1.27):(0.25-0.95).

10. The preparation method according to claim 6, characterized in that: In step (2), the heating reaction time is 10 min to 60 min, the heating reaction temperature is 90° C. to 140° C.; the aging time is 0.5 h to 6.5 h.

11. The preparation method according to claim 6, characterized in that: In step (3), the calcination temperature is 350° C. to 800° C., and the calcination time is 3 h to 10 h; the inert atmosphere is an oxygen-free atmosphere, preferably nitrogen and / or helium.

12. Use of the polyetheramine catalyst according to any one of claims 1 to 5 in the preparation of polyetheramines by catalytic amination of polyether polyols.

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

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