285 results about "Chloromethane" patented technology

The invention relates to the technical field of repair materials, and particularly discloses an extracellular matrix fiber material as well as a preparation method and application thereof. The invention discloses a preparation method of an extracellular matrix fiber material. The preparation method comprises the following steps: taking animal tissues, and carrying out virus inactivation, decellularization and antigen removal, degreasing, drying, grinding and sterilization; the decellularization and antigen removal method comprises the following specific steps: sequentially soaking a sample with a surfactant solution for h; then, soaking treatment is carried out by adopting a salt-alkali solution which contains 0.05-3 mol / L of salt and has the pH value of 8-11; then carrying out soaking treatment by adopting a 0.1-1wt% enzyme solution; and in degreasing, one or more of normal hexane, trichloromethane, dichloromethane, methanol, ethanol, acetone, diethyl ether and ethyl acetate are used for soaking the sample. According to the technical scheme, the ECM powder particle material with high growth factor content is prepared.

The invention discloses a crystal compound, a preparation method thereof and application of the crystal compound in X-ray detection, imaging and anti-counterfeiting encryption, and belongs to the technical field of crystals. The molecular formula of the crystal compound is [Cu (totp) (CH3CN) 3] [Cu2I3 (totp) (PN)]. (CH3CN), wherein totp is tris (o-tolyl) phosphine; and PN is diphenyl-2-pyridine phosphine. The crystal compound disclosed by the invention is simple in preparation method, and has the characteristics of large mass attenuation coefficient of X-ray energy, high light yield and low detection limit when being used as a material of an X-ray detector. The compound also has the characteristic of structural transformation in solvents such as methanol, ethanol, acetone, dichloromethane, tetrahydrofuran and the like, and meanwhile, the conversion of luminescence color under the excitation of 365nm ultraviolet light and X rays is accompanied. The material can be applied to the aspects of scintillator materials, room-temperature X-ray radiation indirect detection materials, radiation detection dosimeters, X-ray scintillator medical imaging, anti-counterfeiting encryption and the like.

The invention relates to the technical field of waste gas treatment, and particularly discloses waste gas treatment liquid for treating large-air-volume low-concentration waste gas through a water-based method. The waste gas treatment liquid for treating the large-air-volume low-concentration waste gas through the water-based method comprises a surfactant, a defoaming agent, a dissolution accelerant and water. Wherein the surfactant can be selected from any one or more of polyoxyethylene alkyl ether, polyoxyethylene alkyl ether and polyoxyethylene fatty acid ester; the dissolution accelerant can be selected from any one or more of ethylene glycol monobutyl ether, diethylene glycol monobutyl ether and triethylene glycol monobutyl ether; the defoaming agent is any one or more of butanol, dimethyl silicone oil, silicone and polyether modified polysiloxane. When the waste gas absorption liquid obtained in the invention is used for treating waste gas, the absorption efficiency of methanol, butanol, benzene, toluene, xylene, ethyl acetate, dichloromethane and acetone is obviously improved, and the absorption efficiency of the waste gas absorption liquid on aromatic hydrocarbon, halogenated hydrocarbon, alcohol, ketone and ester pollutants is improved.

The invention discloses an alkenyl epoxidation method, an epoxy resin monomer and application thereof, and belongs to the field of compound synthesis. Aiming at the problems of high halogen content and low preparation universality of the existing epoxy resin monomer, the invention provides an alkenyl epoxidation method which comprises the following steps: dissolving an aromatic compound in an organic solvent, adding an oxidant and a catalyst into the organic solvent, and extracting after complete reaction to obtain the epoxy resin monomer, the preparation method of the catalyst comprises the following steps: dispersing phosphotungstic acid in hydrogen peroxide to obtain an emulsion; adding a trichloromethane solution of cetylpyridinium chloride into the emulsion, and performing liquid separation after the reaction is completed to obtain a catalyst precursor; the catalyst is obtained. The specific catalyst is used, so that the subsequent reaction catalysis efficiency is higher, and the universality is higher; and no epoxy chloropropane is introduced in the whole process of the alkenyl epoxidation method, so that the halogen content of the finally prepared epoxy resin monomer is low, and the limitation barrier that the use of the conventional epoxy resin monomer is limited due to high halogen content is broken through.

The invention relates to a rapid thin-layer identification method for seven medicinal materials in ten-ingredient nerve-soothing granules. The method is characterized in that two test solutions of a trichloromethane layer and an n-butyl alcohol layer are obtained by a simple, convenient and rapid pretreatment method, the trichloromethane layer can be used for identifying schisandra chinensis, moutan bark and lotus plumule, and the n-butyl alcohol layer can be used for identifying pulp of dogwood fruit, fried gardenia, white paeony root and rhizoma anemarrhenae; the thin-layer identification method disclosed by the invention can be used for identifying 7 medicinal materials in 10 medicinal materials in the whole formula of the ten-ingredient nerve-soothing granules, and is convenient to operate, clear in spots and high in specificity.

The application discloses a continuous system and method for converting low-value glyphosate by-products into high-value chemical products, comprising: pumping low-value glyphosate by-products and alkaline compounds into a constant-temperature conversion kettle for conversion and decomposition, and introducing nitrogen into the top of the constant-temperature conversion kettle to blow off and replace gaseous volatile products generated in the reaction; after gaseous products pass through a buffer tank to capture water vapor, the gaseous products enter a three-stage condenser to recover condensable components into a crude product receiving tank, and the non-condensable components are purified and impurities are removed by an acid absorption system and then utilized; liquid crude product is pumped into a low-temperature vacuum desolventizing kettle to realize separation of condensable components from liquid water, and then enters a two-stage condenser for deep dehydration and separation, and is recovered into a pure product receiving tank. The application realizes a new process for preparing high-purity N,N-diethylmethylamine, and forms a whole-process process system for converting low-value waste materials such as chloromethane, triethylamine and synthetic products thereof into high-value chemical products such as N,N-diethylmethylamine and ethylene.

The invention relates to a post-treatment method and system for chloromethane synthesis, and the post-treatment method comprises the following steps: cooling a chloromethane crude product prepared in a reaction stage through an economizer, and then carrying out gas-liquid separation in a gas-liquid separator, a connecting pipeline between the economizer and the gas-liquid separator is filled with a water flow which flows in a direction opposite to that of the material, so that the temperature of a gas-phase discharge hole in the top of the gas-liquid separator is controlled to be 90-120 DEG C; the separated liquid phase enters a hydrochloric acid buffer tank with a partition plate, and an oil phase and a water phase are separated out; and washing the separated gas phase with water by a water washing tower, and then drying to obtain a chloromethane product. The economizer, the gas-liquid separator with specific temperature control and the hydrochloric acid buffer tank with the partition plate are arranged between the reaction system and the water scrubber, so that three-phase separation of'oil phase silicide-water phase-gas phase 'is efficiently realized, and the oil phase silicide is separated from the chloromethane crude product and does not enter the water scrubber and other subsequent systems; therefore, the problem of pipeline blockage in a post-treatment system is solved.

The present application relates to a kind of preparation method of trifluoromethyl pyrazole compound, belong to the technical field of organic synthesis.The specific method is: (1) trifluoroacetyl ethyl acetate is first with hydrazine hydrate cyclization reaction and generates compound of formula III;(2) under the catalysis of base, compound of formula III is reacted with difluoromethylation reagent and generates compound of formula II;(3) compound of formula II is reacted with methylating agent and obtains compound of formula I;The difluoromethylation reagent is difluoro-monochloromethane or sodium difluoro-monochloroacetate;The methylating agent is chloromethane, bromomethane, iodomethane, dimethyl sulfate or dimethyl carbonate.The present application is prepared by changing reaction route, and the higher-priced raw material methylhydrazine is replaced, and isomer impurity is no longer generated in the product prepared.Not only raw material cost is reduced, but also the purity of product is improved.

The application relates to a method for synthesizing and refining electronic-grade hexachloroethyldisilane, and specifically, trichlorosilane raw material is mixed with protective gas into a raw material buffer tank, a mixed gas obtained through the mixing is subjected to a catalytic synthesis reaction under the irradiation of an ultraviolet light source, a product obtained through the reaction is subjected to condensation separation, gaseous trichloromethane returns to the raw material buffer tank to continuously participate in the synthesis reaction, the mixed liquid in the cold trap is warmed and vaporized, hexachloroethyldisilane is obtained through two-step refining, and the purity of the product hexachloroethyldisilane can reach the electronic grade. The application takes trichlorosilane as the initial raw material, the price of the raw material is low; the photo-catalysis is used as the synthesis process, the synthesis process is simple, the reaction yield is high, energy is saved, and the environment is protected; the two-step method is used for refining and purifying the product, the depth of the refining and the efficiency of the refining are high, large-scale production is suitable, the monopoly of foreign enterprises is broken, and the application has important significance.

The present application belongs to the field of chemical production, and particularly relates to a chloromethane cooling and recycling system and a chloromethane cooling and recycling method. The chloromethane cooling and recycling system comprises a first condenser, a second condenser, a third condenser and a chloromethane recycling tank. The shell side inlet of the second condenser is connected with the tube side outlet of the third condenser, and the tube side inlet of the third condenser is used for passing in liquid chloromethane. The present application uses the vaporization endothermic principle of liquid chloromethane to cool and recycle chloromethane, and is good in economy. Moreover, since the to-be-cooled substance and the refrigerant are both chloromethane, even if mutual leakage occurs in the heat exchange process, the quality of the recycled chloromethane will not be affected and the loss of raw materials will not be caused.

The invention discloses a control method for stably recovering reaction heat of liquid-phase catalytic synthesis of chloromethane, which comprises the following steps: two-way shunting control of synthesis gas and reflux control of synthesis gas condensed acid, the first-way shunting control of the two-way shunting control of the synthesis gas comprises the following steps: enabling the synthesis gas to enter a first heat exchanger through a first control pipeline to vaporize methanol; according to the second-path split-flow control, the synthesis gas enters a second heat exchanger through a second control pipeline in a split-range control mode to be cooled; the first path of shunt control of the reflux control of the synthesis gas condensed acid is to form cascade control through the liquid level and the flow so as to return a liquid component into the synthesis reactor through a reflux pipeline, and the second path of shunt reflux control is to enable the liquid component to enter a hydrochloric acid storage tank through a discharge pipeline. The problem that in the prior art, steam needs to be additionally supplemented for methanol vaporization can be thoroughly solved, and long-time stable operation of the synthetic reaction can be guaranteed.

The invention discloses a high-yield method for reducing dinitro and retaining sensitive protecting groups, which comprises the following steps: adding water, sodium dithionite and sodium carbonate into a container, stirring and clarifying, and dropwise adding a mixed solution containing raw materials; after the reaction is finished, extracting, separating liquid, concentrating, and purifying by silica gel column chromatography to obtain a product and a byproduct; the raw material is a compound containing a carbon-carbon double bond, a p-methoxybenzyl protecting group, a t-butyloxycarboryl protecting group and dinitro. Adding a byproduct into a phosphoric acid mixed solution for reaction; and after the reaction is finished, adding dichloromethane and water, dropwise adding triethylamine to adjust the pH value, extracting, separating liquid, drying, concentrating, and purifying by silica gel column chromatography to obtain the product. According to the method, a sodium hydrosulfite / sodium carbonate system and phosphoric acid step-by-step treatment strategy is adopted, reduction of dinitro is achieved under mild conditions, meanwhile, PMB protecting groups, Boc protecting groups and C-C double bonds are reserved, and the problem that stability and high yield of the protecting groups cannot be considered at the same time in an existing method is solved.

The invention belongs to the technical field of methanol recovery, and particularly relates to a methanol recovery device and method.The methanol recovery device is characterized in that a tower washing water storage tank is used for storing chloromethane tower washing waste water, the tower washing water storage tank is communicated with a distillation still, and the chloromethane tower washing waste water in the tower washing water storage tank is preheated and then sent to the distillation still to be distilled; the distillation kettle is connected with a heater, and the heater circularly heats chloromethane washing tower wastewater in the distillation kettle to be above the boiling point of methanol; aeration pipes are distributed in the distillation kettle, and the magnetic suspension fan is communicated with the aeration pipes after being connected with the lower part of the distillation kettle; the lower part of the condenser is connected with a methanol recovery tank; the magnetic suspension fan volatilizes methanol in the heated chloromethane tower washing wastewater in the distillation kettle through the aeration pipe, and distilled methanol from the distillation kettle is cooled by the condenser and then recovered to the recovered methanol tank. The method improves the methanol recovery yield.

The invention discloses a preparation method of a bilastine intermediate, which comprises the following steps: reacting a compound 5 with thionyl chloride under the conditions that dichloromethane is used as a solvent and DMF (Dimethyl Formamide) is used as a catalyst to generate acyl chloride, and then reacting the acyl chloride with diethylamine to prepare a compound 6; taking dichloromethane as a solvent, and carrying out Friedel-Crafts acylation on the compound 6 and ethyl oxalyl chloride under the condition of anhydrous aluminum trichloride to obtain a compound 7; reducing the compound 7 by using sodium borohydride, liquid caustic soda and a water system to prepare a compound 8; taking dichloromethane as a solvent, and reducing the compound 8 by TMDS under the condition of anhydrous aluminum trichloride to prepare a compound 9; hydrolyzing the compound 9 under the hydrochloric acid condition to obtain a compound 10; and under the condition of thionyl chloride, carrying out esterification reaction on the compound 10 and methanol to prepare the bilastine intermediate TM. The preparation method of the bilastine intermediate, provided by the invention, has the advantages of economical and easily available raw materials, mild reaction conditions, efficient reaction and simple operation, and is suitable for industrial application.

The invention provides a synthetic method of 2-(2-amino-5-bromo-benzoyl) pyridine, and belongs to the technical field of medicine synthesis. A one-pot boiling method is adopted, 2-cyanopyridine and 4-bromaniline are used as raw materials, BCl3 is used as a catalyst, dichloromethane is used as a solvent, a heat preservation reaction is performed for 5-25 hours at the temperature of-10 DEG C to 40 DEG C, and the product 2-(2-amino-5-bromo-benzoyl) pyridine is obtained through ethyl acetate extraction, anhydrous sodium sulfate drying and dichloromethane and petroleum ether recrystallization. According to the preparation method of the 2-(2-amino-5-bromo-benzoyl) pyridine, provided by the invention, butyl lithium with extremely high dangerousness does not need to be used, the reaction steps are simple, the yield is stable, the treatment is easy, and the yield is high.

The invention provides a system and method for recycling methane chloride from methyl chlorosilane synthesis tail gas. According to the method, 85%-90% of methane chloride in the methyl chlorosilane synthesis tail gas is recycled in a three-stage sectional type condensation mode. 90-95% of residual methane chloride is recovered through directional absorption of dichloromethane; and finally, residual methane chloride is recovered in a decompression analysis and reflux impurity removal mode, the total recovery rate of methane chloride is larger than or equal to 99%, the purity of methane chloride is larger than or equal to 99.5%, waste of methane chloride is greatly reduced, high recovery of methane chloride is achieved, and methane chloride can be directly reused in a methyl chlorosilane synthesis reaction.

The application provides a preparation method and application of resveratrol-polylactic acid microspheres, and relates to the technical field of biological agents, quantitative resveratrol is dissolved in methanol as O1 phase; quantitative polylactic acid is dissolved in an oil phase solution (ethyl acetate, dichloromethane, trichloromethane) as O2 phase; ammonium bicarbonate, sodium bicarbonate, sodium chloride and hydrogen peroxide are used as a porogen; O1 phase, O2 phase and the porogen solution are subjected to ultrasonic emulsification to obtain O / O primary emulsion; the O / O primary emulsion is added to a polyvinyl alcohol aqueous solution under stirring to obtain O / O / W multiple emulsion; the obtained O / O / W multiple emulsion is subjected to mechanical stirring to remove the oil phase solution in the O / O / W multiple emulsion, and then is subjected to standing, centrifugation, washing, drying and the like to obtain resveratrol-polylactic acid microspheres with uniform size. The resveratrol-polylactic acid microspheres of the application break through the bottleneck of poor water solubility of resveratrol, can effectively prolong the drug action time, and have good antibacterial effect.

The utility model relates to a kind of chloromethane by-product dilute sulfuric acid concentration recycling device, including with the organic matter separation system being connected with concentration system, organic matter separation system includes sequentially connected hydrolytic kettle, organic matter thermal separation equipment, primary condenser and secondary condenser;Hydrolytic kettle is connected with chloromethane by-product dilute sulfuric acid delivery pipe, desalted water pipeline, hydrogen peroxide delivery pipe respectively, primary condenser is communicated with condensate tank, the condensate tank is communicated with hydrolytic kettle, secondary condenser is communicated with methanol recovery tank, gas phase pipeline respectively, methanol recovery tank is communicated with chloromethane synthesis device;Organic matter thermal separation equipment is communicated with dilute sulfuric acid heater, dilute sulfuric acid heater is communicated with concentration system.The utility model is concentrated before dilute sulfuric acid, first organic matter is separated out in dilute sulfuric acid, not only increase economic value, but also reduce the subsequent dilute sulfuric acid vacuum concentration system's jam risk, improve the operation stability of dilute sulfuric acid vacuum concentration system.

This invention discloses a solid sodium aminosulfonate β-H elimination promoter, its preparation method, and its application, relating to the technical field of β-H elimination promoters. The technical solution is as follows: S1, diethylenetriamine is dissolved in an organic solvent; S2, chlorosulfonic acid organic solution is added dropwise to the diethylenetriamine organic solution at 0-10℃ to carry out the reaction; after the addition is complete, the temperature is raised to continue the reaction; S3, the white solid generated by the reaction is filtered and washed with chloroform and ethanol respectively. The washed white solid is poured into anhydrous methanol and dispersed evenly. The reaction temperature is lowered to 0℃, sodium hydroxide is added for neutralization, and the solvent is removed by vacuum distillation. The resulting pale yellow solid is washed with ethanol and finally dried under vacuum to obtain the solid sodium aminosulfonate β-H elimination promoter. The solid sodium aminosulfonate β-H elimination promoter prepared by this invention has advantages such as high metal salt content, strong alkalinity, and easy separation, making it a promising additive for industrial application.

The application relates to the field of adsorption separation, in particular to a novel ion type bipyridyl group COF material and a preparation method and application thereof. The preparation method comprises the following steps: mixing 2,2',6,6'-tetramethyl-4,4'-bipyridine, 2,2'-bipyridine-5,5'-diformaldehyde, sodium hydroxide, trimethylbenzene and methanol to carry out reaction 1, and COF-CQWU-2 is obtained; the COF-CQWU-2 is placed in a mixed solution of iodomethane and chloroform to carry out reaction 2, and the novel ion type bipyridyl group COF material is obtained. The application successfully designs and prepares a novel ion type bipyridyl group COF material I@COF-CQWU-2 for removing perfluorinated compounds in water, the COF material has the advantages of simple preparation method, high adsorption capacity and recyclability, and the target of selectively adsorbing perfluorinated compounds from water is achieved.

This invention discloses a bio-based toughening agent-modified isosorbide polycarbonate and its preparation method, belonging to the technical field of isosorbide polycarbonate. The method includes the following steps: synthesis of a star-shaped polyester toughening agent, synthesis of isosorbide-decanediol copolycarbonate, and reactive blending. The method for synthesizing the star-shaped polyester toughening agent involves vacuum drying pentaerythritol at 105-115°C for 0.8-1.2 hours, mixing the dried pentaerythritol with ε-caprolactone and stannous octoate under nitrogen protection, heating to 125-135°C, and stirring the reaction under nitrogen atmosphere for 10-14 hours. After the reaction, cooling to 38-42°C, adding dichloromethane to completely dissolve the product, and precipitating it with cold methanol, followed by drying to obtain the star-shaped polyester toughening agent. The modified isosorbide polycarbonate prepared by this invention exhibits high toughness while maintaining excellent transparency.

The invention discloses a method for constructing an alpha-aza-aromatic hydrocarbon substituted propenone compound through dipole reversal alpha-position amination reaction of phosphine-catalyzed acetylenic ketone, and relates to a preparation method of the propenone compound. The reaction of the method can be carried out under the following conditions: small organic molecule triphenylphosphine is used as a catalyst, the temperature is 25-50 DEG C, dichloromethane is used as a solvent, acetylenic ketone and an N-heterocyclic aromatic compound are used as reaction substrates, the corresponding functionalized alkenyl ketone compound is obtained, and the highest conversion rate can reach 99%. The method has the advantages of mild reaction conditions, no use of a metal catalyst, environmental friendliness, wide substrate application range, high yield, simple operation, good regioselectivity and commercially available catalyst, and in addition, the target product alpha-aza-arene substituted propenone has potential biological activity and medicinal value.

The invention relates to the technical field of inorganic porous materials, and particularly discloses a preparation method of pseudo-boehmite for chloromethane. The preparation method comprises the following steps: S1, adding sodium-free aluminum salt, zirconium nitrate pentahydrate and tetrabutyl titanate into a mixed solvent, adding a complexing agent, then adding nano boehmite, uniformly mixing, firstly adjusting the pH value to 7.5-8.0, heating to 25-35 DEG C, mixing, then adjusting the pH value to 5.5-6.0, and mixing to obtain uniform sol; s2, urea and ammonium bicarbonate are mixed and dissolved in water, ammonium zirconium carbonate is added, and a mixed solution B is obtained; and S3, adding the mixed solution B into the uniform sol, uniformly mixing, carrying out gradient heating reaction, and then carrying out solid-liquid separation, washing and drying to obtain the pseudo-boehmite for chloromethane. The prepared pseudo-boehmite for chloromethane has the advantages of extremely low sodium content, high specific surface area and excellent thermal stability.

The application discloses a preparation method and application of a catalyst for cracking 1,2-dichloroethane to produce vinyl chloride, and comprises the following steps: 1) a neodymium ore is leached with hydrochloric acid, and after filtering a leaching solution, potassium chloride is added to form a doped precursor K2[NdCl3]; 2) an active metal oxide is dissolved in hydrochloric acid, and then added into the doped precursor K2[NdCl3] solution, and co-precipitation is carried out by adding alkali to obtain an emulsion of a doped active component; the active metal oxide is at least one of oxides of vanadium, manganese, titanium and scandium; 3) the emulsion of the doped active component is mixed with a liquid carrier to obtain the catalyst; the liquid carrier is one or more of chloroform, carbon tetrachloride, 1,1,2-trichloroethane and chlorobenzene.

The invention relates to the technical field of medicine impurity purification, in particular to a separation and purification method of a high-purity urapidil impurity compound. Comprising the following steps: 1) performing vacuum concentration on urapidil mother liquor to obtain mother liquor concentrate M, adding dichloromethane, then adding 100-200-mesh silica gel, and performing vacuum concentration at 35-45 DEG C until the mother liquor concentrate M is dry; (2) weighing 200-300-mesh silica gel, adding dichloromethane, uniformly mixing, filling into a chromatographic column, and compacting for later use; (3) loading the vacuum concentrate in the step (1) into a chromatographic column, adding anhydrous sodium sulfate, and adding eluent for gradient elution; 4) collecting the eluent when the last eluent is used for elution, and performing reduced pressure concentration at 40-50 DEG C; after the concentration is finished, the urapidil impurity compound M1 can be obtained. According to the method for directly extracting and purifying the impurity compound from the mother liquor for preparing urapidil, the process is simpler, the purity of the purified impurity compound is 96-100%, and the accuracy and precision of the verification and detection method can be improved.

The invention belongs to the technical field of chemical production, and particularly relates to a maltol chlorination neutralization reaction method and application. Comprising the following steps: putting 2m < 3 > of materials in a chlorination hydrolysis kettle into a neutralization kettle, stirring at 80r / min, and cooling to 60 DEG C; adding 1.6 m < 3 > of trichloromethane according to the ratio of the neutralization solution to the trichloromethane being 1: 0.8; introducing ammonia to adjust the pH value to 2.5-3.5, and standing for layering for 10 minutes; preheating the heavy phase to 120 DEG C, feeding the heavy phase into a sublimation kettle (vacuum is-0.065 to-0.096 MPa, and kettle temperature is less than 220 DEG C), sublimating, and freezing and centrifuging to obtain a maltol crude product; and freezing and centrifuging the light phase to obtain ammonium chloride salt. The method provided by the invention has the advantages of fast reaction, high yield, reduction of sewage amount and treatment cost, and improvement of device safety, and is suitable for ethyl maltol production.

The invention discloses a separation system and a separation method of a dichloromethane, ethanol and methanol aqueous solution multi-element azeotropic system. The separation system comprises three stages of rectifying towers connected in series; a reflux pipeline with a condenser is connected to a tower top extraction port of each stage of rectifying tower, and the reflux pipeline corresponding to the first stage of rectifying tower is also connected with a mixer for mixing tower top extraction substances of the first stage of rectifying tower with water and a phase splitter for separating oil and water in the mixer; a water phase outlet of the phase splitter and a tower kettle extraction opening of the first-stage rectifying tower are respectively connected with a feeding opening of the second-stage rectifying tower; a methanol extraction opening is formed in the side line of the second-stage rectifying tower; a tower kettle extraction opening of the second-stage rectifying tower is connected with a feeding opening of the third-stage rectifying tower; and a device for separating ethanol and water is connected to a tower top extraction port of the third-stage rectifying tower. The method provided by the invention can effectively separate the dichloromethane, ethanol and methanol aqueous solution multi-element azeotropic system, and the obtained dichloromethane, ethanol and methanol products have high purity.

The invention belongs to the field of rubber materials, and particularly relates to a high-strength heat-resistant soluble rubber material and a preparation method thereof.The preparation method comprises the following steps that a powdery anhydride-terminated polyimide prepolymer is dissolved in DMF, then a catalyst dibutyltin dilaurate solution is added, perfluorobutyl ethyl isocyanate is slowly dropwise added, stirring is carried out, and a mixture is obtained; the polyimide fluorine-containing end-capped copolymer is obtained; dissolving the imide fluorine-containing end-capped copolymer in dry dichloromethane, adding a catalyst boron trifluoride diethyl etherate complex, and introducing ethylene oxide gas into the reaction liquid to obtain a primary hydroxyl-capped fluorine-containing imide block copolymer; a primary hydroxyl-terminated fluorine-containing imide segmented copolymer is used as a soft segment; the high-strength heat-resistant soluble rubber material is prepared through a prepolymer method by taking 4, 4 '-diphenylmethane diisocyanate as a hard segment, and the soluble rubber material is prepared through a primary hydroxyl-terminated, fluorine-containing and imide-block-containing soft segment, so that breakthrough of high strength, high heat resistance and good solubility is realized.