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CN-122010745-A - Preparation process for synthesizing tert-butylamine by adopting methyl tert-butyl ether

CN122010745ACN 122010745 ACN122010745 ACN 122010745ACN-122010745-A

Abstract

The invention belongs to the technical field of preparation of tert-butylamine, and particularly relates to a preparation process for synthesizing tert-butylamine by adopting methyl tert-butyl ether. The preparation process comprises the following steps of preparing calcium alginate microspheres, preparing SAPO precursor liquid, carrying out composite crystallization, preparing an SAPO-11 carrier, preparing an ammonium type SAPO-11 carrier, preparing a metal supported catalyst, preparing an activated catalyst, and preparing tert-butylamine under the catalysis of the activated catalyst by taking methyl tert-butyl ether and liquid ammonia as raw materials. According to the preparation process for synthesizing tert-butylamine by using methyl tert-butyl ether, the process of synthesizing tert-butylamine by using methyl tert-butyl ether and ammonia as raw materials is carried out by following an acid catalytic cracking nucleophilic addition coupling mechanism, and the prepared hierarchical pore CuZn/HSAPO11 catalyst is used for preparing high-purity tert-butylamine by the synergistic effect of B acid, L acid and metal active sites, so that the reaction activation energy is obviously reduced, and the high-activity and high-selectivity catalytic conversion at low temperature is realized.

Inventors

  • CHEN GUOJIAN
  • WANG ZHENZHEN
  • DENG XINLIN
  • ZHANG BO
  • HAO JINXIA
  • WANG ZHENMING
  • GAO HONGLI
  • WANG WENWEN
  • YU RUJUN
  • LI WEIZHEN
  • GUO WENJIE
  • WANG MENG
  • HU JIANGYU
  • ZHAO YANG
  • CHEN GUOHUA
  • CAO ZHENLI

Assignees

  • 山东达民化工股份有限公司

Dates

Publication Date
20260512
Application Date
20260402

Claims (9)

  1. 1. A preparation process for synthesizing tert-butylamine by methyl tert-butyl ether is characterized by comprising the following steps: (1) Adding sodium alginate and starch into deionized water, stirring in a water bath at 40 ℃ for 2 hours to obtain a composite glue solution, adding the composite glue solution into liquid paraffin-Span 80 mixed solution, stirring at a high speed of 800r/min for 12 minutes to form an emulsion, dripping 0.2mol/L calcium chloride solution into the emulsion, continuously stirring for 30 minutes, crosslinking and solidifying at room temperature for 80 minutes, centrifuging at a rotating speed of 3000r/min for 5 minutes to separate microspheres, washing with deionized water for 3 times to obtain wet calcium alginate gel microspheres, drying the wet calcium alginate gel microspheres in a vacuum freeze dryer at-50 ℃ for 24 hours until the quality of the microspheres is not changed, preparing semi-dry microspheres, classifying the semi-dry microspheres by an air classifier, and screening to obtain microspheres with a particle size of 40-50 mu m; (2) Preparing SAPO precursor liquid; (3) Composite crystallization, namely directly adding the microspheres with the particle size of 40-50 mu m prepared in the step (1) into the SAPO precursor liquid prepared in the step (2) for constant temperature crystallization; (4) Washing, drying and calcining to prepare the SAPO-11 carrier; (5) Washing with acid to remove calcium carbonate, washing with water and drying to prepare an ammonium type SAPO-11 carrier; (6) Impregnating an active metal to prepare a metal supported catalyst; (7) Activating the metal supported catalyst to prepare an activated catalyst; (8) Methyl tertiary butyl ether and liquid ammonia are used as raw materials to prepare tertiary butyl amine under the catalysis of an activated catalyst.
  2. 2. The preparation process for synthesizing tert-butylamine by methyl tert-butyl ether according to claim 1, wherein the starch in the step (1) accounts for 15% of the mass of sodium alginate; the mass volume of sodium alginate and deionized water in the step (1) is 1.5:100, and the unit is g/mL; The liquid paraffin-Span 80 mixed solution in the step (1) is prepared by adding Span80 into liquid paraffin, and stirring until the Span80 is completely dissolved, wherein the mass volume ratio of Span80 to the liquid paraffin is 6:500, and the unit is g/mL; in the step (1), the volume ratio of the composite glue solution to the liquid paraffin-Span 80 mixed solution is 1:5; Step (1), dripping the composite glue solution into liquid paraffin-Span 80 mixed solution, and controlling the dripping speed to be 3mL/min; the concentration of the calcium chloride solution in the step (1) was 0.2mol/L.
  3. 3. The preparation process for synthesizing tert-butylamine by methyl tert-butyl ether according to claim 1, wherein the preparation method of the SAPO precursor liquid in the step (2) is characterized in that pseudo-boehmite is added into deionized water and stirred uniformly, phosphoric acid is then added dropwise into the mixture, stirring is continued for 1h until the mixture is completely clear and transparent, ethyl orthosilicate is added and stirred for 1h until the ethyl orthosilicate is fully hydrolyzed, di-n-propylamine is finally added and stirred for 1h until gel is uniform, the gel is placed in a 90 ℃ water bath and aged for 24h, the SAPO precursor liquid is prepared, wherein the mass ratio of the pseudo-boehmite to the deionized water is 1:8, the content of firing base Al 2 O 3 is 68 percent, the mass concentration of the phosphoric acid is 85 percent, the molar ratio of the phosphoric acid to the Al 2 O 3 is controlled to be 1.1:1, the molar ratio of the ethyl orthosilicate to the Al 2 O 3 is controlled to be 0.15:1, the molar ratio of the pseudo-boehmite to the Al 2 O 3 is controlled to the Al 2 O 3 , and the molar ratio of the pseudo-boehmite to the Al 2 O 3 is controlled to be 2.4984.
  4. 4. The preparation process for synthesizing tert-butylamine by methyl tert-butyl ether according to claim 1, wherein the specific step of compound crystallization in the step (3) is characterized in that microspheres with the particle size of 40-50 μm prepared in the step (1) are directly added into the SAPO precursor liquid prepared in the step (2), after ultrasonic dispersion for 15min, stirring is carried out at room temperature for 2h, stirring is stopped, the mixture is transferred into a polytetrafluoroethylene lining high-pressure reaction kettle, the temperature is raised to 180 ℃ at a rate of 1.5 ℃ per min, the mixture is crystallized for 30h at a constant temperature under autogenous pressure, and finally the mixture is naturally cooled to the room temperature, wherein the mass ratio of the microspheres with the particle size of 40-50 μm to the SAPO precursor liquid is 1:8-12.
  5. 5. The process for preparing the SAPO-11 carrier by adopting methyl tertiary butyl ether synthesis according to claim 1, wherein the step (4) is characterized in that the step of washing, drying and calcining is carried out, namely, pouring out supernatant, taking out solid crystallized at constant temperature, centrifugally washing the obtained solid for 4-5 times by using deionized water, washing until the pH value of washing liquid is=7, then drying at 110 ℃ for 12 hours to obtain powder, placing the powder into a muffle furnace for calcining, and cooling to room temperature along with the furnace after the calcining is finished, so as to prepare the SAPO-11 carrier, wherein the calcining is carried out under an air atmosphere, heating to 120 ℃ at a heating rate of 2 ℃ per minute, then carrying out heat preservation for 2 hours at a heating rate of 2 ℃ per minute, and finally carrying out heat preservation for 4 hours at a heating rate of 5 ℃ per minute, wherein the SAPO-11 carrier is prepared.
  6. 6. The process for preparing tert-butylamine synthesized by methyl tert-butyl ether according to claim 1, wherein the acid washing to remove calcium carbonate and the water washing to dry in the step (5) are specifically characterized in that the SAPO-11 carrier is immersed in 0.1mol/L hydrochloric acid, stirred at room temperature for 1h, then the solid is filtered out, immersed in 0.5mol/L ammonium chloride solution, stirred at 80 ℃ for 2h for isolation exchange, then centrifugally washed with deionized water to pH=7.0, and finally dried at 110 ℃ for 12h, thus obtaining the ammonium SAPO-11 carrier, wherein the mass-volume ratio of the solid to the ammonium chloride is 1:10, and the unit is g/mL.
  7. 7. The preparation process for synthesizing tert-butylamine by methyl tert-butyl ether according to claim 1, wherein the preparation process is characterized in that in the step (6), the impregnating active metal is used for preparing a metal supported catalyst, namely, copper nitrate and zinc nitrate are dissolved in deionized water to prepare a mixed solution, an ammonium SAPO-11 carrier is subjected to isovolumetric impregnation, standing and aging are carried out for 12 hours at room temperature after the impregnation is finished, and then drying and roasting are carried out, so that the metal supported catalyst is prepared, wherein the drying temperature is 110 ℃, the drying time is 12 hours, the roasting atmosphere is air, the roasting temperature is 500 ℃, the roasting time is 4 hours, the mass of copper oxide accounts for 5.5-5.7% of the total mass of the catalyst, the mass of zinc oxide accounts for 3.4-3.6% of the total mass of the catalyst, and the mass of an ammonium SAPO-11 carrier accounts for 90.8-91.0% of the total mass of the catalyst.
  8. 8. The process for preparing tert-butylamine by methyl tert-butyl ether synthesis according to claim 1, wherein the activating treatment is carried out on the metal supported catalyst in the step (7), the activated catalyst is prepared by loading the metal supported catalyst prepared in the step (6) into a fixed bed reactor, introducing hydrogen atmosphere, heating to 365-375 ℃ at a heating rate of 2 ℃ per minute, reducing at constant temperature for 3.6-3.7h, and cooling to 165-170 ℃ in the hydrogen atmosphere after the reduction is finished, thus obtaining the activated catalyst.
  9. 9. The process for preparing tert-butylamine by methyl tert-butyl ether synthesis according to claim 1, wherein the step (8) is characterized in that methyl tert-butyl ether and liquid ammonia are used as raw materials, under the catalysis of an activated catalyst, methyl tert-butyl ether is sent into a preheating vaporizer A through a metering pump, vaporization temperature is controlled to be 115 ℃ to be gas phase, liquid ammonia is sent into a preheating vaporizer B through a metering pump, high-pressure overheated gaseous ammonia is converted into the liquid ammonia at the temperature of 2.0MPa and 145 ℃, the two materials are fully mixed in a mixer to obtain overheated mixed raw materials, the overheated mixed raw materials are heated to 175 ℃ through the preheater C and enter a reactor, gas phase continuous catalytic ammonolysis reaction is carried out from top to bottom through a catalyst bed layer, reaction effluent is cooled to 25 ℃ through a reactor outlet condenser, the unreacted methyl tert-butyl ether is condensed into liquid phase, unreacted gaseous ammonia is sent into a rectifying tower for normal pressure operation after the liquid phase ammonia is separated through gas-liquid phase compression circulation, the condensed liquid phase product is absorbed and removed through a water washing tower, the temperature is controlled to be 44 ℃, the temperature of the high-purity tert-butyl amine product is obtained from the tower top, the temperature is 60 ℃, the temperature of the tower is 60 ℃ and the unreacted methyl tert-butyl ether is taken to be 1.25 mol/1.0.1, the molar ratio of methyl tert-butyl ether is equal to 1.25 m.

Description

Preparation process for synthesizing tert-butylamine by adopting methyl tert-butyl ether Technical Field The invention belongs to the technical field of preparation of tert-butylamine, and particularly relates to a preparation process for synthesizing tert-butylamine by adopting methyl tert-butyl ether. Background Tert-butylamine is an important organic synthetic intermediate and is widely used in synthetic rubber vulcanization accelerators, drugs (rifampicin), pesticides, bactericides, herbicides, dyes and the like. The main method for producing tert-butylamine at present is (1) HCN-MTBE method, namely hydrocyanic acid-methyl tert-butyl ether method. MTBE and hydrocyanic acid are firstly subjected to the action of concentrated sulfuric acid to generate tertiary butyl formamide, and then methanol is used for alcoholysis to generate tertiary butylamine. However, there is a great risk in production because of cyanide in the process route. (2) The urea tert-butyl alcohol process includes the reaction of urea and tert-butyl alcohol at 10-20 deg.c to produce tert-butyl urea and subsequent hydrolysis under alkaline condition to obtain tert-butyl amine. The synthesis of tert-butylamine in the route uses high-boiling point solvent-ethylene glycol, and the high-boiling point solvent-ethylene glycol can be recycled, but has high energy consumption and poor effect. (3) The catalytic ammonification method of isobutene is to prepare tert-butylamine by direct gas-phase catalytic ammonification of isobutene and ammonia. Under 300 ℃ and 500MPa, iron-silicon is used as a catalyst, the ratio of ammonia to isobutene is 5:1, the selectivity of the obtained tert-butylamine is 97.6%, diatomite is used as a catalyst, the ratio of ammonia to isobutene is 2:1, the selectivity of the obtained tert-butylamine is 99.8% under 300 ℃ and 250MPa, and unreacted raw materials can be recycled. The process is required to be under high temperature and high pressure, has strict process conditions and is not suitable for domestic production. (4) The hydrolysis method of N-tert-butyl phenylacetamide is successfully developed by German Bayer company in 1983, the mass fraction of tert-butylamine is 95.6%, and the total yield of the two steps is more than 75%. Or the phenylacetic acid and tert-butylamine can be prepared by reacting phenethylwax with tert-butanol to prepare N-tert-butyl phenylacetamide and alkaline hydrolysis. But this process is difficult to produce on a large scale. In summary, the existing tert-butylamine production process has the problems of relatively harsh reaction conditions, high energy consumption, poor safety, difficulty in large-scale production and the like. Therefore, it is necessary to explore a novel process for preparing tert-butylamine. Disclosure of Invention The invention aims to provide a preparation process for synthesizing tert-butylamine by adopting methyl tert-butyl ether. The tert-butylamine prepared by the process has higher yield and purity. The preparation process for synthesizing tert-butylamine by methyl tert-butyl ether comprises the following steps: (1) Adding sodium alginate and starch into deionized water, stirring in a water bath at 40 ℃ for 2 hours to obtain a composite glue solution, adding the composite glue solution into liquid paraffin-Span 80 mixed solution, stirring at a high speed of 800r/min for 12 minutes to form an emulsion, dripping 0.2mol/L calcium chloride solution into the emulsion, continuously stirring for 30 minutes, crosslinking and solidifying at room temperature for 80 minutes, centrifuging at a rotating speed of 3000r/min for 5 minutes to separate microspheres, washing with deionized water for 3 times to obtain wet calcium alginate gel microspheres, drying the wet calcium alginate gel microspheres in a vacuum freeze dryer at-50 ℃ for 24 hours until the quality of the microspheres is not changed, preparing semi-dry microspheres, classifying the semi-dry microspheres by an air classifier, and screening to obtain microspheres with a particle size of 40-50 mu m; (2) Preparing SAPO precursor liquid; (3) Composite crystallization, namely directly adding the microspheres with the particle size of 40-50 mu m prepared in the step (1) into the SAPO precursor liquid prepared in the step (2) for constant temperature crystallization; (4) Washing, drying and calcining to prepare the SAPO-11 carrier; (5) Washing with acid to remove calcium carbonate, washing with water and drying to prepare an ammonium type SAPO-11 carrier; (6) Impregnating an active metal to prepare a metal supported catalyst; (7) Activating the metal supported catalyst to prepare an activated catalyst; (8) Methyl tertiary butyl ether and liquid ammonia are used as raw materials to prepare tertiary butyl amine under the catalysis of an activated catalyst. Wherein, in the step (1), the starch accounts for 15 percent of the mass of the sodium alginate. In the step (1), the mass volume of sodium alginate and deionized water is