7869 results about "Ethylic acid" patented technology

The invention discloses a catalyst for preparing alcohol by acetic ester hydrogenation as well as a preparation method and an application thereof, which is characterized in that the main catalyst of the catalyst is copper or copper oxide or a mixture of the copper and the copper oxide, and the cocatalyst can be also added, wherein the cocatalyst is one or more of oxides of zinc, manganese, chromium, calcium, barium, iron, nickel and magnesium; and the carrier is alumina or silica sol. The catalyst has high activity and high selectivity under the condition of low temperature and low pressure, thus greatly reducing the investment cost of permanent plants, lowering production energy consumption, being extremely beneficial for the industrial production, and having good stability and long service life. The catalyst of the invention is used to cause percent conversion of a reaction of converting the acetic ester into the alcohol is more than or equal to 80% and the selectivity of the alcohol is more than or equal to 95%.

A catalyst for synthesizing vinyl acetate from acetylene and acetic acid is prepared from activated carbon, zinc acetate and alkaline bismuth carbonate in mass ratio of 100: (27-40): 0.026 by excessive solution dipping method.

The room temperature ionic liquid containing unsaturated double bond has the general expressino of A+B-, where A+ contains R1 being hydroxyl with 1-4 carbon atoms and R2 containing 2-20 carbon atoms and at least one double bond; and B- is one of anions, including chlorate radical, bromate radical, iodate radical, acetate radical, sulfate radical, nitrate radical, tetrafluorobromate radical, etc. Its preparation is to mixture and react olefin halide R1X and N-alkyl imidazole to obtain ionic liquid dialkyl imidazolium halide. The present invention also relates to the application of the ionic liquid in dissolving cellulose and preparing cellulose derivative.

The invention discloses a specific nanometer paint of energy-saving environment-protective typed aluminium alloy section bar (door and window), which comprises the following parts: 90-100% filming agent, 0.1-10% hardener, 0.5-8% levelling agent, 0.5-10% nanometer material, 20-50% fill and 10% hollow microball, wherein the filming agent is one or more of epoxy resin, polyester resin, acrylic acid resin, amino resin, phenol resin or alkide resin; the hardener is one or more of dicyandiamide, imidazole, dihydrazide, polybasic carboxylic acid, beta-hydroxyalkyl amide or triglycidol isocyanuric ester hardener; the levelling agent is one or more of polyacrylic resin, siliceous acryl resin, polyvinyl butyral, benzoin, hydrocastor oil, cellulose acetate butyrate or epoxy soy oil; the nanometer material is nanometer zinc oxide; the hollow micro-ball is hollow ceramic microball.

The invention discloses a multifunctional textile finishing agent. The multifunctional textile finishing agent comprises the following components in percentage by weight: 1.00 to 5.00 percent of fibroin, 0.01 to 0.10 percent of chitosan, 0.01 to 0.50 percent of titanium dioxide, 0.01 to 1.50 percent of cross-linking agent, 0.50 to 5.00 percent of acetic acid, 0.10 to 0.80 percent of metal salt catalyst and the balance of water. The ecological multifunctional textile finishing agent involved by the invention is made of environment-friendly raw materials, is convenient to process, is not toxic or harmful to a human body and have no pollution; a finishing method is simple and is suitable for industrial production by a padding method; and the appearance of a finished textile is not influenced, namely the color does not turn yellow and the finished textile has a good anti-wrinkle effect and comfortable handfeel.

The invention relates to a transparent super-amphiphobic surface layer and a layer-by-layer in-situ spraying reaction preparation method. The method comprises the steps of sequentially spraying priming paint solutions and finishing paint solutions on a base body in a layer-by-layer in-situ mode through a spraying gun and by adopting the same spraying technology, sequentially spraying acetic acid water solutions of 1 wt.% and fluorine-silicane solutions of 0.1-2 wt.%, carrying out curing at normal temperature and then obtaining a transparent super-amphiphobic surface. The priming paint solutions are obtained by adding hydrophobic transparent resin and corresponding curing agents into soluble solvents and then dispersing the mixtures ultrasonically until the resin is completely dissolved; the finishing paint solutions are obtained by adding hydrophilic fumed silica into ethyl alcohol and forming solutions ultrasonically. According to the invention, the preparation technology for needed coatings is simple, the spraying technology is easy and convenient to operate, coatings are super-hydrophobic, super-oleophobic and highly transparent, and the application prospect is wide in the fields of solar panels, glasses and automobile windshield glass.

The invention provides a completely new process route for synthesizing dexamethasone and series products thereof. The invention adopts 1, 4, 9, 16-tetraene-pregna-3, 20-diketone as the original material which is modified by 9, 11bits, 16, 17 bits and 21 bits so as to obtain the dexamethasone and the series products thereof such as dexamethasone acetate and dexamethasone sodium phosphate and the like. The process has the advantage that the invention adopts the existing intermediates of manufacturers as the original material; the route is simple; the materials are available; the use of expensive accessories is avoided; the yield and the cost are dramatically better than that of the prior methods used for synthesizing the dexamethasone and derivatives thereof; moreover, the adoption of the existing intermediates realizes the combined-line prodction of the betamethasone series products and the dexamethasone series products, thus greatly reducing the manufacturing cost and the industrial manufacturing condition.

A multiphasic method of contraception comprising the steps of sequentially administering to a female of child bearing age a Phase I composition containing a progestogen in an amount equivalent to about 0.3 to about 1.5 mg norethindrone acetate and an estrogen in an amount equivalent to about 5 to about 15 mcg of ethinyl estradiol for about 7 to about 14 days; a Phase II composition containing a progestogen in an amount equivalent to about 0.3 to about 1.5 mg of norethindrone acetate and an estrogen in an amount equivalent to about 10 to about 25 mcg of ethinyl estradiol for about 14 to about 22 days; a Phase III composition containing a progestogen in an amount equivalent to about 0.3 to about 1.5 mg of norethindrone acetate and an estrogen in an amount equivalent to about 15 to about 35 mcg of ethinyl estradiol for about 20 to about 31 days; and an optional Phase IV composition containing (i) an estrogen in an amount equivalent to about 5 to about 20 mcg of ethinyl estradiol, or (ii) a placebo or a non-steroidal component, or (iii) a combination of (i) and (ii), for about 2 to about 8 days. The ethinyl estradiol equivalent amount of estrogen in each of the successive Phases II and III is at least 5 mcg greater than the ethinyl estradiol equivalent amount of estrogen in the immediately-preceding phase.

The invention provides a completely new process route for synthesizing betamethasone and series products thereof. The invention adopts 1, 4, 9, 16-tetraene-pregna-3, 20-diketone as the original material which is modified by 9, 11 bits, 16, 17 bits and 21 bits so as to obtain the betamethasone and the series products thereof such as betamethasone acetate and betamethasone sodium phosphate and the like. The process has the advantage that the invention adopts the existing intermediates of manufacturers as the original material; the route is simple; the materials are available; the use of expensive accessories is avoided; the yield and the cost are dramatically better than that of the prior methods used for synthesizing the betamethasone and derivatives thereof; moreover, the adoption of the existing intermediates realizes the combined-line production of the betamethasone series products and dexamethasone series products, thus greatly reducing the manufacturing cost and the industrial manufacturing condition.

The invention discloses a synthetic method of a covalent organic framework (COF) material. The method comprises the following steps: after mixing 1,3,5-benzenetricarboxaldehyde with 2,5-di(N,N-dimethyl)amino-1,4-benzdihydrazide uniformly in an organic solvent, reacting in the presence of a catalyst acetic acid to obtain the COF material, wherein the mole ratio of 1,3,5-benzenetricarboxaldehyde to 2,5-di(N,N-dimethyl)amino-1,4-benzdihydrazide is 1:(0.5-3). The COF material obtained by adopting the method has relatively large specific surface area and regular open framework structure with adjustable diameter, thus being beneficial for mass transfer of reactants and products in photoabsorption and catalytic processes; the material can serve as a photocatalyst and can increase the yield of the dehydrogenative coupling reaction between 2-phenyl-1,2,3,4-tetrahydroisoquinoline and nitromethane from 39% in the absence of catalysts to 89%.

The invention discloses polymorphs A, B, C and D of abiraterone acetate. A preparation method of the polymorphs comprises the step of re-crystallizing the abiraterone acetate subjected to the separation and the purification of a chromatographic column in different solvents. Through stable investigation, four polymorphs have favorable stability and flowability, can be used as raw materials for storage and transportation and are suitably applied to antitumor medicinal preparations.

The invention discloses a preparation method of essence microcapsules. The preparation method comprises the following steps: (1) dissolving chitosan in acetum; (2) adding emulsifier and essence into the chitosan acetum for high-speed emulsification and dispersion to obtain the chitosan essence emulsion; (3) adding the mixed solution of sodium alginate and sodium tripolyphosphate dropwise into the chitosan essence emulsion; (4) adjusting the pH value of the system to 5-7 with NaOH solution to obtain the condensed essence microcapsules; and (5) adding cross-linking agent into the condensed essence microcapsule system to perform chemical cross-linking process on the condensed essence microcapsules to obtain the essence microcapsules. For the essence microcapsules prepared according to the method disclosed by the invention, as chemical cross-linking process is implemented on the walls of the capsules, the density of the capsule walls and the resistance to the solution alkalinity / acidity are improved, and the application stability of the essence microcapsules is increased; moreover, with small size, the capsules can easily permeate into textile fiber, and the water-washing resistance of the textile fiber is greatly improved.

A drilling fluid or mud additive having several components, including leonardite (humic acid); potassium acetate; partially hydrolyzed polyacrylamide (PHPA); polyanionic cellulose polymer (PAC); sulfonated asphalt; sulfoalkylated tannin; polystyrene maleic anhydride copolymer; micronized cellulose fiber; and calcium carbonate. These components are preferably premixed in a dry formulation as a powder or as pellets, and shipped to the site in bags or bulk tanks. This offers substantial advantages over the prior art in that the drilling mud of the present invention may be formed simply by adding the dry mix to a predetermined amount of water, and is thus much easier to make than the prior art wet mix drilling fluids, which typically require precise ratios of several different powders and liquids to be mixed together. Hydration buffers help keep the powder or pellets dry and flowable.

The invention discloses a preparation method of biological carbon by using grapefruit skin. The method is as below: drying and pulverizing grapefruit skin, and mixing the grapefruit skin with an aqueous solution of catalyst, and conducting a hydrothermal carbonization reaction; after the hydrothermal carbonization reaction, washing and drying to obtain the biological carbon. The temperature of the hydrothermal carbonization reaction is 160 DEG to 260 DEG C; the catalyst is at least one selected from phosphoric acid, sulfuric acid, hydrochloric acid, acetic acid, citric acid, acrylic acid, sodium polyacrylate, sodium polystyrene sulfonate, zinc chloride, and stannic chloride. In addition, the invention also comprises the biological carbon which is prepared by the method and the application of the biological carbon in the adsorption of heavy metals. The biological carbon material obtained by the invention has the advantages of microsphere particle shape, uniform particle size and high adsorption capacity, and can be applied to the field of adsorption and remediation of heavy metal pollutants or organic pollutants.

The invention provides a boiler coal combustion-improving desulfurizing and denitrifying agent composition. The composition comprises the following raw materials in parts by weight: 2-7 parts of sodium carbonate, 1-3 parts of alumina, 2-8 parts of aluminium hydroxide, 2-5 parts of ferric trichloride, 2-6 parts of ferric oxide, 3-10 parts of potassium permanganate, 3-10 parts of potassium chlorate, 10-35 parts of activated attapulgite clay, 15-30 parts of urea, 2-4 parts of ammonium formate, 2-4 parts of ammonium chloride, 6-23 parts of ammonium acetate, 3-9 parts of manganese oxide, 9-12 parts of copper chloride, 1-3 parts of copper oxide, 2-4 parts of zinc sulfate, 1-3 parts of zinc nitrate, 7-18 parts of potassium dichromate, 1.0-1.5 parts of titanium dioxide, 0.5-1.0 part of barium molybdate, 0.5-1.5 parts of cobalt sulfate, 0.5-1.5 parts of vanadium pentoxide, 0.3-0.7 part of cerium oxide, 0.1-0.2 part of sodium dodecyl benzene sulfonate and 0.1-0.2 part of alkyl glyceryl ether. The composition is convenient to use, has stable properties, plays roles of combustion improving, desulfurization and denitrification, has coal saving rate of 8-25% and can remove fixed sulfur by 50-70%.

The invention discloses a sheath-core polylactic acid tobacco tow and a filter stick and a preparation method thereof. A single fiber in the tow has a sheath-core structure consisting of an inner core and a sheath; main body resins of a sheath layer and a core layer are polylactic acid; the weight ratio of a sheath layer resin to a core layer resin is 20:80-40:60; the crystallinity degrees of the sheath layer and the core layer of the tow are 3-25 percent and 25-60 percent respectively; and the smelting points of the sheath layer and the core layer are 120-150 DEG C and 150-175 DEG C respectively. Compared with the prior art, the sheath-core polylactic acid tobacco tow has the greatest characteristics that the advantages of the core layer and the sheath layer are combined, high physical and mechanical properties and high heat resistance are provided by using the core layer, and high bonding property is provided by the sheath layer. A common plasticizing agent (such as glycerol triacetate) can be conveniently used for molding the filter stick. Moreover, the core layer and the sheath layer of the sheath-core polylactic acid tobacco tow provided by the invention have high biodegradability, and the sheath-core polylactic acid tobacco tow is an environment-friendly tobacco tow.

The invention relates to a polysiloxane coating composition belonging to a coating chemical manufacturing technology. The polysiloxane coating composition is obtained by reacting hydrogenated epoxide resin and amino-functionalized siloxane and combining acrylic resin with good coating performance and weatherability and polyetheramine resin with excellent flexibility and adhesion. The invention particularly relates to a polysiloxane coating composition applied to offshore oil platforms. The polysiloxane coating composition has weather-proof, water-proof and corrosion-resistant performances, good flexibility and excellent ply adhesion. The polysiloxane coating composition comprises the following ingredients of 12-50 of epoxide resin, 10-40 of acrylic resin, 0.5-1.5 of dispersant, 20-30 of titanium pigment, 5-25 of French chalk, 5-15 of mica powder, 0.5-1.5 of rheological agent, 0.5-2 of anti-settling agent, 2-10 of dimethyl benzene, 5-10 of butyl acetate, 15-40 of curing agent 1 and 5-25 of curing agent 2 according to the weight percent.

The invention discloses a sulfide functionalized covalent organic frame material, The material has a structural unit shown in the specification, and is obtained by the following steps: adding 2,5-Bis(3-(ethylthio)propoxy)-terephthalohydrazide and benzenetricarboxaldehyde into a mixed solvent of 1,4-dioxane and mesitylene, adding an aqueous acetic acid solution into the above mixture and reacting at 120 DEG C for 1-3 days. The material has a mesoporous structure, has BET specific surface area of 470-480 m<2>?g<-1>, has good selective identification for mercury ions, and can be used for removal of the mercury ions.

The invention relates to a method for preparing an NCC / CS / PVA composite nanofiber membrane. NCC is rod-shaped particles, wherein the diameter of each particle ranges from 20 nm to 60 nm, and the particles are highly crystallized. The method comprises the steps that (1) an NCC / CS solution is prepared, wherein the concentration of the NCC, by weight, ranges from 0.09% to 0.21%; (2) an NCC / PVA solution is prepared, wherein the concentration of the NCC, by weight, ranges from 0.4% to 0.8%; (3) an acetic acid solution, tetraethyl orthosilicate, the NCC / CS solution obtained in the step (1) and processed through ultrasound, and the NCC / PVA solution obtained in the step (2) and processed through ultrasound are mixed to obtain a spinning solution, and the nanofiber membrane is obtained through the electrospinning technology, wherein the mass ratio of the acetic acid solution to the tetraethyl orthosilicate to the NCC / CS solution to the NCC / PVA solution is (2.5-3.5):(1.5-2.5):5:5; (4) the obtained nanofiber membrane is immersed in an alkaline solution for 2-6 hours at the normal temperature, and the membrane structure can be stable. The method for preparing the NCC / CS / PVA composite nanofiber membrane has the advantages that the nanofiber material preparation process is simple, the preparation process is environmentally friendly and free of pollution, nanofibers are excellent in mechanical performance, the surface of the nanofiber membrane is rich in modifiable functional groups, and the nanofiber membrane has a remarkable affinity effect on biomacromolecule.

The invention relates to a guided tissue regeneration membrane, which comprises a compact coating and a loose coating, wherein the compact coating is composed of collagen-I or collagen-I composite hyaluronic acid; and the loose coating is composed of collagen-I or collagen-I composite calcium salt. A preparation method of the guided tissue regeneration membrane comprises the following steps of: preparing a collagen solution or a collagen and hyaluronic acid mixed solution by the use of acetic acid; injecting the solution into a self-made die, and drying it in the air to prepare the compact coating; injecting the collagen solution or a mixed liquor of the collagen solution and calcium salt onto the compact coating, and uniformly spreading; precooling the die at ultralow temperature, followed by freeze-drying to prepare the guided membrane with the compact coating and loose coating structure; carrying out vacuum high-temperature crosslinking and chemical crosslinking; and finally cleaning. The regeneration membrane has good histocompatibility and mechanical strength, low antigenicity and strong guided tissue regeneration capability. Its degradation rate in vivo is 3-8 months. The method is easy to operate, is suitable for automatic and continuous large-scale production, and solves the problems of large size of collagen membrane and material uniformity during industrial production.

The invention discloses an aluminum-doped zinc oxide film coating and nano-rod array material as well as a preparation method thereof. The aluminum-doped zinc oxide film coating and nano-rod array material comprises the components based on the weight percentage: 95-99% of zinc oxide and 1-5% of aluminum-doped quantity. The preparation method adopts a sol-gel method, zinc acetate and aluminium nitrate are added with organic solvent according to the proportion for heating under reflux; the mixed solution is then added with certain quantity of stabilizing agent for water bath heating at certain temperature and added with organic reagents such as absolute ethyl alcohol, methanamide or methanol and the like to prepare sol according to the need; after that, a spin coating method is adopted to form a film, and the aluminum-doped zinc oxide nano film coating material can be obtained by the processes such as drying, pretreating, repeatedly spin coating, annealing, secondary annealing under the atmosphere of hydrogen and nitrogen and the like; then, a hydrothermal method is adopted for preparing highly oriented aluminum-doped zinc oxide nano-rod and array thereof. The invention has high utilization rate of the raw materials, low cost and simplified preparation technique, and can control the performance and the particle size of the material from the molecular design level.

The invention discloses a method for synthesizing methyl propionate by ethylene. The methyl propionate is prepared from the materials: ethylene, methanol, carbon monoxide and water under existence of a catalyst in a carbonyl combination manner; and the adopted catalyst is a composite catalyst system taking palladium acetate as a main catalyst, and metal ions such as cobalt, nickel or ruthenium and the like as a promoter. The method disclosed by the invention has good catalytic activity and selectivity at a low temperature and low pressure; the composite catalyst system has the advantages of low consumption, good selectivity, long service life and the like; carbonyl synthesis of the methyl propionate from the ethylene can be efficiently catalyzed; the reaction result is based on the ethylene; the yield of the methyl propionate is greater than 95%; and the entire method has good commercial value.

The invention provides salt coating liquid. The salt coating liquid is made with, by weight, 0.5-10% of calcium acetate and 90-99.5% of tobacco sheet coating liquid. After treated by a high-temperature process, the calcium acetate in the salt coating liquid is partially decomposed into calcium carbonate which can convert on the surface of the reconstituted tobacco into a great amount of calcium carbonate particles, so that retention rate and distribution uniformity of the calcium carbonate in the reconstituted tobacco can be significantly improved, specific area is greatly increased, a novel microporous structure is generated, water absorbing and moisture preserving performances of the structure are effectively improved, whiteness and flame retention rate of ash from combustion of the reconstituted tobacco can be improved, bulkiness of the reconstituted tobacco is improved, and thickens of the reconstituted tobacco is increased; in terms of smell absorption, tobacco miscellaneous odors can be decreased, irritation is lowered and comfort is improved. In addition, the undecomposed calcium carbonate is hydratable calcium salt with very high hygroscopic property; good moisture preserving effect and certain mould resistance are provided.

Disclosed are a compound germ power product and its method of production, which belongs to microorganism preparation producing field, especially relates to a compound power product for producing kimchi and its method of production, has solved the technical problem of supplying a compound of lactobacillus,lactobacillus casei and brew microzyme which are separately cultured, separated, added with protective agent and drying process, then each germ power acquired are mixed with a certain ratio, generating the compound germ power to be directly used in kimchi production. The invention can change the traditional method of production of natural fermentation for kimchi, remarkably simplify the manufacturing technique, shorten its producing period, has wide application, and is benefit for the development of kimchi industry.

The invention discloses a plastic paint with simulated electroplating effect. The composition and the weight ratio of the invention are as follows: 30 to 45 of acrylic resin with 50 percent of solid content and 70 to 90 DEG C of Tg, 20 to 30 of cellulose acetate butyrate with 20 percent of solid content, 8 to 12 of triad copolymer vinyl chloride-acetate resin with 30 percent of solid content, 6 to 10 of non-floating aluminum and silver pulp with an average diameter less than or equal to 20 Mum, 0.3 to 0.5 of dispersant, 0.2 to 0.4 of flatting agent, 0.4 to 0.6 anti-settling agent, 6.0 to 10.0 of toluene, 3.5 to 6.0 of ethyl acetate, 3.5 to 6.0 methy isobutyl ketone, 3.0 to 5.0 of isobutanol and 4.0 to 7.0 of glycol butyl ether. The special diluent of the invention, according to the weight ratio, is made from the following components evenly mixed: 20 of white gas, 10 of toluene, 22 of ethyl acetate, 15 of acetone, 25 of isobutanol and 8 of glycol butyl ether. The main paint which comprises the composition and the diluent are evenly mixed according to the ratio of 1: 2-3, then the mixture is used for spray coating; the metallic appearance of the paint film obtained is very close to the effect of the electroplating, and the paint film has good alcohol resistance with high hardness and strong wear resistance, and also has simple process. The aluminum and silver pulp used is a common type, the cost of which is only 5 percent to 10 percent of the simulated electroplating aluminum and silver pulp and about 2 percent of electrosilvering.

A process for producing acetic acid is disclosed. The process comprises carbonylating methanol to form a reaction mixture comprising a catalyst, catalyst stabilizer, acetic acid, methanol, methyl iodide, methyl acetate, water, and carbon monoxide and introducing at least a portion of the reaction mixture to a distillation column to separate into a bottom steam comprising the catalyst and catalyst stabilizer, a sidedraw stream comprising acetic acid and water, and an overhead stream comprising methanol, methyl acetate, methyl iodide, and water. The process of the invention eliminates the use of flash tank.

The invention relates to a method for preparing ethanol through acetic ester hydrogenation. The method performs an acetic ester hydrogenation reaction to generate ethanol under the conditions of certain temperature, pressure, hydrogen / ester molar ratio and hydrogen circulation in a fixed-bed reactor filled with a copper-based catalyst, wherein in the copper-based catalyst, a mesoporous molecular sieve MCM-41 is used as a carrier, copper is used as an active component, and the oxide of at least one element of La and Ce is used as an auxiliary; and the MCM-41 accounts for 40-90% of the catalyst by weight, the active component copper accounts for 10-50% of the catalyst by weight, and the auxiliary accounts for 0.1-20% of the catalyst by weight. According to the method for preparing ethanol through acetic ester hydrogenation, provided by the invention, when the reaction temperature is 220 DEG C, the reaction pressure is 3MPa, the hydrogen / ester molar ratio is 30 and the mass airspeed of acetic ester is 2h<-1>, the conversion rate of acetic ester is 98.5%, and the ethanol selectivity is as high as 99.6%, thereby showing extremely high hydrogenation activity, selectivity and stability.

The invention discloses a method for preparing a nanofibre membrane, belonging to a technique for preparing a nanofibre compound membrane. The method comprises the following steps: preparing curcuminethanol solution and chitosan acetum, mixing the curcumin ethanol solution and the chitosan acetum by the volume ratio thereof to prepare spinning solution which is injected into an injector of an electrostatic spinning device for electrostatic spinning to form a compound nanofibre membrane and to obtain a curcumin / chitosan nanofibre membrane of antibacterial property, wherein the diameter of thecurcumin / chitosan nanofibre membrane is 200-400 nm. The invention has the advantages that the preparation process is simple, the prepared membrane material heals wound, has broad spectrum bactericidalproperty and has higher bacterial inhibition rate to colibacillus and staphylococcus aureus for 24h.

The invention discloses a method for dissolving chitosan through combined use of acid and alkali. The method comprises the steps of mixing lithium hydroxide, potassium hydroxide, urea and water according to mass percentage, so as to obtain an alkaline aqueous solution; adding a chitosan raw material into an acetic solution or hydrochloric solution, and carrying out stirring dispersion for 20-60 seconds, so as to obtain a chitosan-containing solution; uniformly stirring and mixing the alkaline aqueous solution and the chitosan-containing solution according to the volume ratio of 1: 1, freezing and unfreezing, thereby obtaining a chitosan solution. According to the method, acidic-alkaline solvent systems are used in a combined manner, so that an alkaline system solution of chitosan is obtained, and the degradation of chitosan in an acidic solution is avoided; moreover, the processes of swelling and solvent system pre-cooling are not required, so that the dissolving time is shortened, and the dissolving efficiency is increased.