245 results about "Acid hydrolysis" patented technology

The invention relates to the technical field of preparation of composite carbon sources, and discloses a method for preparing a micromolecular composite carbon source by using soapstock acidified leftovers, which comprises the following steps: pretreatment: centrifugally separating the soapstock acidified leftovers, recovering crude fatty acid, and regulating the pH value of the water phase to 5.0-6.0 by using an alkaline regulator, performing enzymolysis, namely adding compound protease into the pretreated water phase, performing enzymolysis reaction at 45-55 DEG C, performing organic acid hydrolysis, namely adding small molecular organic acid into a system subjected to enzymolysis, adjusting the pH value of the system to 2.0-4.0, performing hydrolysis reaction at 85-100 DEG C, performing neutralization and post-treatment, cooling the system after the hydrolysis is completed, neutralizing the pH value of the system to 5.5-6.5 by adopting an alkaline substance, and performing post-treatment to obtain a finished product. And filtering to obtain the small molecular carbon source. The alkaline substance is potassium hydroxide, ammonia water or urea. According to the method for preparing the micromolecular composite carbon source by utilizing the soapstock acidified leftovers, the waste liquid, which is the soapstock acidified leftovers generated in the grease refining process and is difficult to biochemically treat, can be converted into the micromolecular composite carbon source with high market value.

The invention discloses an analysis method for determining the content of galactosamine in sulfated polysaccharide based on high-temperature hydrochloric acid hydrolysis and an ion chromatograph method, which comprises the following steps: hydrolyzing a test sample with hydrochloric acid at high temperature to release galactosamine, separating with an ion chromatograph and a sugar analysis column, detecting with a pulsed ampere detector, and determining the content of galactosamine in sulfated polysaccharide according to a galactosamine reference substance. And quantitatively analyzing the content of galactosamine in the test sample. The method disclosed by the invention has the advantages of simplicity, rapidness, accuracy, high efficiency, no need of derivation treatment and the like.

The application discloses an amino acid hydrolysate acid removal process using indirect MVR evaporation, and particularly relates to the technical field of amino acid hydrolysate acid removal processes, and comprises the following steps: S1, amino acid hydrolysate conveying, S2, hydrolysate evaporation under reduced pressure, S3, acid substance gas-liquid separation, S4, secondary steam conveying, and S5, liquid storage. The acid substance in the amino acid hydrolysate is evaporated and acid removal treated by adopting the MVR evaporation technology, so that the hydrolysate can form concentrated liquid and acid substance after being separated under reduced pressure, the generated acid substance is separated by a gas-liquid separator, and acid liquid and secondary steam are generated, the secondary steam can provide a secondary steam source for an evaporator after being compressed by a compressor, thereby providing a large amount of steam source for the evaporator, reducing the emission of acid gas, improving the resource utilization rate, achieving the protection of the environment, and avoiding the harm of acid gas to the human body.

The utility model discloses a hot galvanizing assistant tank which comprises an assistant tank body, a drain valve is arranged at the bottom of the assistant tank body, fixing plates are arranged on two sides of the upper end of the assistant tank body, a support is fixedly connected to the fixing plates, a filter screen frame is arranged below the support, an electric heating pipe is arranged at the bottom end in the assistant tank body, and the electric heating pipe is connected with the electric heating pipe. A stirring device is arranged in the plating assisting tank and located above the electric heating pipe, and a lifting turnover device is arranged in the support and connected with the filter screen frame. The utility model belongs to the technical field of plating assisting tanks, and particularly relates to a plating assisting tank for hot galvanizing, which solves the problem that impurities easily fall to the bottom of the plating assisting tank and are inconvenient to clean when a workpiece is subjected to acidolysis cleaning in the prior art.

The application provides a grafted modified starch, a preparation method thereof and a low-temperature sizing application. The acid hydrolysis starch is used as a raw material, the acid hydrolysis starch has a lower molecular weight, a relatively less hydrogen bond structure in the molecule, a relatively increased porosity of the system, and small molecules are more easily entered into the interior of the starch; the acid hydrolysis starch is modified by using acrylic acid and vinyl acetate, so that the grafted starch has more carboxyl and hydroxyl groups on the molecular structure, the hydrophilicity of the modified starch can be further increased, the starch can be low-temperature gelatinized, the purpose of low-temperature sizing is achieved; then the carboxyl-hydroxyl starch is esterified, and ester groups are introduced, so as to adjust the hydrophilicity and hydrophobicity of the modified starch, the introduction of the hydrophobic groups can reduce the viscosity of the sizing material and improve the fluidity of the sizing material, meanwhile, the introduction of the specific ester groups can also increase the affinity of the gelatinized sizing material to fibers, improve the applicability to various textile fabrics, and solve the problems that the adhesion of the original starch sizing material to the yarn is not strong, and the sizing film is hard and brittle.

The present invention belongs to the field of detection and relates to a method for determining guar gum content. The method comprises: extracting guar gum from reconstituted tobacco leaf base by soaking and shaking with an aqueous solution; evaporating the extract to dryness; decomposing the guar gum into mannose and galactose by acid hydrolysis; and then detecting the mannose and galactose contents by ion chromatography, thereby converting the guar gum content. The method can accurately determine the guar gum content in reconstituted tobacco leaf base and is simple to operate.

This invention discloses a method for determining the content of suberin monomers in the suberized tissue of yam tubers. Suberin is a macromolecular polyester, with monomers mainly covalently linked by oxygen-ester bonds. Its aliphatic compounds are linked to the polysaccharide components in the cell wall by glycosidic bonds and located on the inner side of the cell wall. Therefore, to determine the suberin monomer content, it is necessary to first destroy the plant cell structure, and then hydrolyze the oxygen-ester bonds between the suberin monomers to release the suberin monomer components. This invention first uses ultrasonic pretreatment to destroy plant cells, and then uses lipase hydrolysis combined with ultrasonic assistance and acid hydrolysis (sulfuric acid / methanol) to fully and efficiently hydrolyze the suberin into monomers. The reagents used are relatively safe and non-toxic, and the operation is relatively simple, solving the technical problem of difficult determination of suberin monomer content in the study of suberin metabolism after yam tuber injury healing.

This invention discloses a method for determining the arsenic content in ores, belonging to the field of ore element detection technology, comprising the following steps: (1) weighing the ore sample, adding hydrochloric acid-nitric acid mixed acid for acid hydrolysis, then adding hydrofluoric acid and perchloric acid for auxiliary digestion, evaporating to near dryness, and dissolving the residue with hydrochloric acid; (2) adding a thiourea-ascorbic acid-citric acid mixed reducing masking agent to reduce and mask interfering ions; (3) using an atomic fluorescence spectrometer to determine the fluorescence intensity of arsenic in the sample solution, and calculating the arsenic content according to the standard curve. This method achieves accurate and stable determination of arsenic in various ores such as phosphate rock and iron ore by optimizing sample pretreatment conditions, improving the reduction system and matrix interference suppression strategy.

This invention discloses a method for the synthesis of furfural and ethanol from green coconut (Cocos nucifera L.) husk. The method involves chemical reaction for furfural production and a biological fermentation for ethanol synthesis. In the chemical step, the green coconut husk undergoes acid hydrolysis in a high-pressure reactor, yielding furfural. The residual waste from this step is then utilized as a substrate for fermentation by Saccharomyces cerevisiae, producing ethanol. The integrated approach efficiently converts the cellulosic and hemicellulosic components of the green coconut husk into two industrially valuable compounds, furfural and ethanol, from a single agricultural waste stream. The invention provides a cost-effective and environmentally sustainable method for resource utilization and waste reduction.

The utility model relates to the technical field of acidolysis tail gas treatment, in particular to an acidolysis tail gas treatment device which comprises a venturi scrubber, a gas-liquid separator, a filler scrubbing tower, an induced draft fan and an exhaust funnel, and a body consists of an anti-blocking nozzle, a contraction section, a throat pipe and a diffusion section; the gas-liquid separator is composed of a body, a demister, a liquid level detection control instrument and the like. The filler washing tower is composed of a body, filler, a spraying distributor, a demister, a washing tower circulating pump, a washing tower drain pipe, a liquid level detection control instrument and the like. Process water provided by the utility model is only supplemented to the sulfuric acid mist filler washing tower, the washing tower discharges or overflows to the venturi scrubber, and the venturi scrubber is not supplemented with the process water and is only suitable for circulating liquid of the sulfuric acid mist filler washing tower, so that the sulfuric acid concentration and the dust concentration of the circulating liquid of the sulfuric acid mist filler washing tower can be reduced to the maximum extent; the highest absorption efficiency is guaranteed, the possibility of scaling and blocking is avoided, and meanwhile the overall water discharge amount is reduced.

The invention relates to a method for synchronously preparing metastannic acid through ultrasonic enhancement and hydrolysis of low-concentration nitric acid, and belongs to the technical field of metastannic acid preparation. The preparation method comprises the following steps: slowly adding high-purity tin sheets into a dilute nitric acid solution in batches under the stirring condition at the temperature of 35-60 DEG C, and uniformly mixing to obtain a mixed system; and at the temperature of 35-60 DEG C, ultrasonic waves are applied to the mixed system for an ultrasonic enhanced oxidation dissolution-hydrolysis reaction for 30-50 min, so that tin sheets are oxidized and dissolved and are synchronously hydrated to generate metastannic acid precipitates, solid-liquid separation is carried out, solids are sequentially washed and dried, and a high-purity metastannic acid product is obtained. A passivation layer on the surface of the tin sheet is destroyed by utilizing the mechanical effect of ultrasound, and mass transfer is accelerated; the ultrasonic cavitation effect is used for promoting particle refinement and gel network depolymerization, and tin ion hydrolysis is promoted. The method is carried out at normal pressure, low acidity and low temperature, no nitrogen oxide brown smoke is generated in the whole reaction process, the metastannic acid yield is larger than or equal to 95%, and the method has the advantages of being mild in reaction, environmentally friendly, high in efficiency and good in product purity.

The invention relates to the field of lily pyran production, and discloses a method for obtaining lily pyran by acidifying and hydrolyzing a rectification backing material, which comprises the following steps: S1, raw material proportioning and reaction starting: respectively pumping the lily pyran rectification backing material and an acid catalyst solution into a microreactor from two feeding channels according to a mass ratio of 1.0: (0.7-1.0); s2, continuous feeding: in the process of pumping the valley pyran rectification base material and the acid catalyst solution in the step S1 into the microreactor along two feeding channels, respectively controlling the feeding speeds, and mixing in the microreactor to obtain a mixture; according to the method, available components such as uncyclized precursors and oligomers in the rectified backing material are directionally converted through an acidification hydrolysis process, the backing material treated as hazardous waste in a traditional process is converted into a convallaria majalis pyrane finished product, the total utilization rate of raw materials is remarkably increased, and thousands of tons of resource waste is reduced every year; meanwhile, the hazardous waste incineration or landfill cost is saved, and the economic burden is further reduced.

The present application belongs to the field of biotechnology, and particularly relates to a biosynthesis gene cluster of fungal polyketide compounds and application thereof. The present application provides a heterologous expression method of an aspertaichunol compound biosynthesis gene combination, and a compound aspertaichunol B is obtained through the method, and a compound aspertaichunol A is prepared through acid hydrolysis of the aspertaichunol B, which has important significance for future research and development of an efficient biosynthesis method for preparing the aspertaichunol compound.

This invention discloses a method for determining the content and simultaneously identifying the source of polyglutamic acid (PCA) in fertilizers based on microwave digestion-high-resolution liquid chromatography-mass spectrometry (LC-MS), belonging to the field of analytical detection technology. The method includes: microwave-assisted acid hydrolysis of fertilizer samples to obtain a hydrolysate; injecting the hydrolysate into a liquid chromatography-high-resolution mass spectrometry (LC-MS) instrument, performing a single injection analysis in data-independent acquisition (DIA) mode, and simultaneously acquiring a mass spectrometry dataset containing a full-scan fingerprint of the parent ion and fragment information of the daughter ion by alternating between low and high collision energies; extracting the precise mass number of PCA from the dataset for accurate quantification, and calculating the PCA content using the difference method; simultaneously retrieving the total ion chromatogram and inferring the source of PCA based on the response of other amino acids. This invention is the first to introduce microwave digestion pretreatment and high-resolution mass spectrometry DIA acquisition mode into the field of PCA detection in fertilizers, requiring only a single injection to simultaneously complete accurate quantification and source identification, effectively avoiding false positives caused by background of plant and animal protein hydrolysates, and significantly improving the efficiency and confidence of PCA detection in complex matrix fertilizers.

The application provides a detection method for the content of crude fat in pet feed, and the detection method comprises the following steps: (1) acid hydrolysis pretreatment: adding hydrochloric acid solution into the pet feed to be detected, heating to micro boiling, keeping, cooling, filtering, obtaining residues, and washing to neutral; (2) freezing treatment: freezing the residues washed to neutral; (3) first weighing: drying the residues after the freezing treatment, adding glass beads, drying and cooling, and weighing to obtain m1; (4) extraction: Soxhlet extraction, controlling the temperature to make the refluxing times 10-20 times / hour, and extracting for 1-3 hours; (5) second weighing and (6) calculation: obtaining the content of crude fat X. Through the modification of the detection steps and the solvent, the application can realize the rapid detection of the content of crude fat in pet feed, has good accuracy, can meet the detection and formula research and development requirements of the pet feed, and provides technical support for the research and development and standard development of the pet feed.

The invention relates to a method for extracting dihydroquercetin and arabinogalactan from larch, which is characterized by comprising the following steps: by taking larch root as a raw material, carrying out ultrasonic extraction once by using a natural surfactant assisted ethanol solution, adding ethanol into the remaining extracting solution, precipitating crude polysaccharide in the extracting solution in an alcohol precipitation manner, filtering after alcohol precipitation, and drying to obtain the dihydroquercetin and arabinogalactan. Drying the filter cake in a drying oven to obtain crude polysaccharide (containing arabinogalactan); adding an acid and an organic solvent into the filtrate, completely converting glycoside into aglycone in an acid hydrolysis manner, separating out an organic solvent phase after the reaction is finished, concentrating and directly drying the organic solvent, dissolving a solid matter with hot water, enriching with macroporous adsorption resin, eluting, and recrystallizing to obtain a product. The operation process has the main characteristics that the raw materials can be directly used without drying, the energy consumption is low, the macroporous adsorption resin purification process is pollution-free, the production efficiency is high, and the yield is high; all solvents can be recycled, so that industrial large-scale production is facilitated.

This invention relates to the field of analytical chemistry, and in particular to a method for the quantitative determination of total phosphate in aquatic products using acid hydrolysis combined with liquid chromatography-tandem mass spectrometry. The method exhibits good linearity for orthophosphate in the range of 0.1–20.0 mg / L, with a correlation coefficient of 0.9991, a limit of detection of 0.03 g / kg, a limit of quantitation of 0.10 g / kg, and low matrix effect. At spiking levels of 1.0–10.0 g / kg, the intra-day recoveries for shrimp and fish are 89.8%–102.8% and 88.7%–105.8%, respectively; the inter-day recoveries are 90.9%–106.4% and 90.2%–105.8%, respectively; the intra-day RSD is ≤10.0%, and the inter-day RSD is ≤9.6%. This method features simple pretreatment, strong anti-interference capabilities, high sensitivity, and excellent accuracy and precision. It is suitable for the detection of total phosphate in aquatic products, providing a reliable technical means for the supervision of total phosphate in aquatic products, and is highly practical.

Provided is an adhesive composition and the like, the adhesive composition being for forming an adhesive protective layer that protects a to-be-protected surface of a substrate when manufacturing an electronic component device, the adhesive composition containing: a compound that generates an acid by irradiation with an active energy ray; and a polymer having, in a molecule, an ester group that is hydrolyzed by the acid to generate a hydrophilic group.

The invention provides modified tartary buckwheat sprout acidic polysaccharide, a preparation method thereof and application of the modified tartary buckwheat sprout acidic polysaccharide in preparation of a medicine or health food with an immune enhancement function. The tartary buckwheat sprout acidic polysaccharide is rich in polygalacturonic acid (HG) and I-type polyrhamnogalacturonic acid (RG-I) pectin structural domains, and has remarkable in-vivo immune enhancement activity. The tartary buckwheat bud seedling acidic polysaccharide is subjected to structural targeting modification through a controllable partial acid hydrolysis technology and a directional enzyme digestion technology, and by comparing the in-vivo immune enhancement activity of the tartary buckwheat bud seedling acidic polysaccharide before and after targeting modification, it is found that the immune enhancement activity of the tartary buckwheat bud seedling modified acidic polysaccharide is remarkably superior to that of the tartary buckwheat bud seedling acidic polysaccharide.

The invention belongs to the technical field of crystal growth, and particularly relates to a Cs3Cu2I5 single crystal growth method. The method specifically comprises the following steps: taking cesium iodide and cuprous iodide as precursors, carrying out stirring reaction on the precursors and lewis acid in a polar aprotic solvent, hydrolyzing the lewis acid to generate an acid environment, inhibiting Cu < + > oxidation, and meanwhile, forming uniformly dispersed colloidal particles to obtain a precursor solution; and adding an anti-solvent into the precursor solution to enable the precursor solution to reach a supersaturated state, filtering, and carrying out single crystal growth by adopting an inverse temperature crystallization method. Lewis acid is added into the precursor solution, oxidation of Cu < + > is inhibited by utilizing a weak acid environment generated by hydrolysis of the Lewis acid, and the colloid stability of the precursor is improved, so that growth of the high-quality large-size Cs3Cu2I5 single crystal is promoted. The method is simple and convenient to operate and easy to control, can effectively improve the scintillation luminescence performance of the single crystal, and has a wide application prospect.

The invention discloses p-methoxybenzylamine as well as a preparation method and application thereof, and belongs to the field of acyclic or carbocyclic compounds. The preparation method comprises the following steps: (1) adding p-methoxybenzaldehyde into a reaction container, sequentially adding an ethanol solution and ammonia water, heating and stirring, and reacting at 50-90 DEG C in a normal pressure environment; after the reaction, carrying out reduced pressure distillation to obtain p-methoxybenzylimine; the molar ratio of the p-methoxybenzaldehyde to the ammonia water is 1: (1-1.3); (2) dissolving p-methoxybenzylimine in methanol, adding a sodium hydroxide solution and 4-dimethylaminopyridine, then adding sodium borohydride, and reacting at the temperature of 0-30 DEG C under normal pressure; after the reaction is completed, adding acid into a product for hydrolysis; and adjusting the product to be alkalescent, extracting, drying, filtering and distilling to obtain the p-methoxybenzylamine. A new strategy for synthesizing p-methoxybenzylamine is introduced, the reaction does not involve high temperature, and the reaction conditions are milder and more controllable.

The utility model belongs to the technical field of titanium dioxide chemical industry, and relates to a feeding device of a continuous acidolysis reactor, which comprises a reaction cylinder, a mixture feeding pipeline and an initiating acid feeding pipeline, the top surface of the reaction cylinder is fixedly connected with the initiating acid feeding pipeline, the mixture feeding pipeline is inserted on the initiating acid feeding pipeline, and the initiating acid feeding pipeline is connected with the reaction cylinder. A pipeline protecting and cleaning assembly is arranged at a discharging port of the mixture feeding pipeline, a stirring device is installed in the reaction cylinder, and a discharging port is formed in the edge of the bottom of an inner cavity of the reaction cylinder. According to the utility model, a sleeve feeding mode is formed by the mixture feeding pipeline and the initiating acid feeding pipeline, so that the mixture feeding pipeline and the initiating acid feeding pipeline are synergistically fed without influencing each other, and scabs formed by premature reaction of the mixture and the initiating acid in the pipelines are effectively avoided; and the pipeline protecting and cleaning assembly is used for further preventing scabbing and blocking at the outlet of the mixture feeding pipeline, so that the production efficiency of the continuous acidolysis reactor is improved, and the downtime is shortened.

The application provides a composite oxide coated modified positive electrode material and a preparation method thereof, a secondary battery, and a preparation method of the composite oxide coated modified positive electrode material, which comprises the following steps: mixing a silicon source and a titanium source, and performing acid hydrolysis to prepare a composite sol; mixing positive electrode material particles and the composite sol, and allowing the composite sol to gel on the surface of the positive electrode material particles to prepare a gel layer on the surface of the positive electrode material particles; and performing heat treatment on the positive electrode material particles with the gel layer on the surface in an oxidizing atmosphere, so that the gel layer is converted into a composite oxide coating layer and coated on the surface of the positive electrode material particles. The preparation method provided by the application can allow the composite of the multi-element coated oxide to be carried out at the molecular level, and the composite oxide coating layer formed has a heterogeneous interface with chemical bonding between the two phases, which is beneficial to improving the structural integrity and long-term cycle stability of the coating layer.

The invention discloses a preparation method of N-methyl o-fluoroaniline, which is characterized in that o-fluoroaniline is used as a starting raw material, and a target product is efficiently synthesized through three steps of reaction: step 1, in the presence of a solvent and alkali, o-fluoroaniline and acetyl chloride are acetylated at low temperature to generate 2-fluoro-acetanilide, and the product is directly used for the next step after being roughly purified; 2, under the action of a solvent and alkali, carrying out controllable methylation on the 2-fluorine-acetanilide and dimethyl carbonate to obtain 2-fluorine-N-methylacetanilide; and 3, removing acetyl protection through acidic hydrolysis, and adding sodium thiosulfate to prevent oxidation to finally obtain a high-purity product. According to the method, excessive methylation is avoided through an acetyl protection strategy, the process does not need high-risk operations such as ultralow temperature and high pressure, the operation is simple and convenient, the energy consumption is low, and the product purity is gt; the total yield reaches 79.86%, and the method is green, safe and suitable for industrial production.

This invention relates to the field of bioengineering technology, specifically to a cis-epoxysuccinate hydrolase mutant and its applications. The cis-epoxysuccinate hydrolase mutant is obtained by single-point or multi-point mutations at positions 127 and 141 of the amino acid sequence of the wild-type cis-epoxysuccinate hydrolase shown in SEQ ID NO. 1. The single-point mutation involves replacing valine at position 127 with isoleucine, or replacing aspartic acid at position 141 with threonine. The cis-epoxysuccinate hydrolase mutant obtained by this invention exhibits high thermal stability, significantly improving the service life of the cis-epoxysuccinate hydrolase in the industrial production of D(-)-tartaric acid.

The utility model provides a device for removing liquid adhered to the surfaces of solid particles. The device comprises a conveying chain assembly, a suction filtration assembly, filter cloth and a first filter pressing roller, a plurality of suction filtration assemblies are arranged on the surface of the conveying chain assembly in the annular direction of the conveying chain assembly, the suction filtration assemblies are wrapped with the filter cloth in the annular direction, the conveying chain assembly can drive the filter cloth to rotate in the annular direction, the filter cloth is used for bearing solid particles and permeating liquid media, and the suction filtration assemblies are used for suction filtration of the liquid media permeating through the filter cloth. The plurality of first filter pressing rollers are respectively arranged below the suction filtration assembly at the advancing straight line section of the conveying chain assembly; the conveying chain assembly drives the filter cloth to rotate, so that the first filter pressing roller sequentially extrudes the bottoms of the suction filtration assemblies, and solid-liquid separation is achieved. The device for removing the liquid adhered to the surfaces of the solid particles is simpler and more energy-saving, and can effectively solve the problem that the liquid adhered to sugar precipitation particles and lignin particles needs to be separated in the process of producing sugar by hydrolyzing plant fiber raw materials with concentrated acid.

The invention discloses a glycosyl hydrolase derived from intestinal bacteria and application of the glycosyl hydrolase. A glycosyl hydrolase gene for catalyzing trillioside to be hydrolyzed into diosgenin is cloned from intestinal microorganism enterococcus faecalis for the first time, and protein coded by the glycosyl hydrolase gene is identified as multifunctional glycosyl hydrolase; the diosgenin can be catalyzed to generate diosgenin, and the hydrolysis of other saponins such as steroid saponin and C3, C6 and C21 glycosyl of ginsenoside can be catalyzed, so that a basis is provided for the biological enzymolysis of the diosgenin and other saponins or sapogenin. Meanwhile, biological enzymolysis of the diosgenin makes up for the defects of high production cost, serious environmental pollution and the like of a traditional acid hydrolysis method, and the diosgenin has a great application prospect.

The invention relates to the technical field of high polymer materials, in particular to a high-toughness nylon material and a synthesis method thereof. The preparation method adopts a three-step strategy of'protection-polycondensation-hydrolytic conversion ', and comprises the following steps: firstly, reacting a 4-p-toluenesulfonyl aminophenol protective agent with a polyether amine prepolymer with an ester bond side chain to protect an ester bond; secondly, the protected prepolymer and dicarboxylic acid are subjected to efficient polycondensation at the temperature of 160-230 DEG C, and a high-molecular-weight nylon polymer is obtained; and finally, by controlling acid hydrolysis conditions, removing a protecting group, and converting an ester bond side chain into an active carboxylic acid side chain at the same time. The method breaks through the traditional synthesis bottleneck, and the prepared nylon material has excellent mechanical properties brought by high molecular weight and functionality endowed by carboxylic acid side chains, and has important industrial application value.

The invention discloses a method for producing oligosaccharide by cooperatively treating aspergillus niger residues through multiple enzymes. The method comprises the following steps: mixing pretreated aspergillus niger residues with hydrochloric acid, carrying out acidolysis wall breaking, and carrying out suction filtration on an obtained wall-broken mixture; carrying out mixed treatment on filtrate obtained by suction filtration with cellulase and beta-glucanase, filtering, and carrying out concentration and alcohol precipitation on supernate to obtain soluble beta-glucan oligosaccharide; performing filter residue enzymolysis on filter residues obtained by suction filtration by using mesoporous silica immobilized chitinase, and recovering the immobilized chitinase after enzymolysis; and filtering the mixed solution subjected to enzymolysis by using the immobilized chitinase, and carrying out alcohol precipitation on the supernate to obtain the N-acetylglucosamine and the chitosan oligosaccharide. According to the method disclosed by the invention, the aspergillus niger residues are jointly treated by adopting multiple enzymes, the yield of N-acetylglucosamine and chitosan oligosaccharide reaches 85.1%-88.5%, and the yield of beta-glucosamine oligosaccharide reaches 86.7%-89.3%. The invention provides a brand new route for producing various oligosaccharides by utilizing solid waste aspergillus niger residues in the fermentation industry.