76results about How to "Avoid separation and purification" patented technology

The invention discloses a method for identifying uronic acid-containing polysaccharide in a biological tissue. The method comprises the following steps: 1, extracting crude polysaccharide in the biological tissue; 2, hydrolyzing the crude polysaccharide with trifluoroacetic acid, and removing acid from the obtained hydrolysate; 3, carrying out derivatization on the residues obtained from the step 2 with 1-phenyl-3-methyl-5-pyrazolone to prepare derivatives of sugar; 4, preparing a reference solution from the identified uronic acid-containing polysaccharide by the methods in the step 2 and the step 3; and 5, analyzing and extracting the derivatives of sugar from the step 3 and the reference substance from the step 4 by a liquid chromatogram-mass-spectrometric technique, and identifying the uronic acid-containing polysaccharide in the biological tissue by comparison. According to the method, the polysaccharide in the biological tissue can be directly detected; fussy separation and purification processes are avoided; the used sample amount is relatively low; and the result can be obtained within a relatively short period of time.

The invention discloses a method for removing residual bimetallic catalyst in a polyether polyol product with low degree of unsaturation, which is characterized by adopting the adsorption method to remove the catalyst, and can greatly simplify the process flow, reduce impurities introduced into the product, realize high purification rate, improve the stability of late-stage storage of the polyether polyol with low degree of unsaturation, improve the product quality and be widely applied in the purification of the polyether polyol with low degree of unsaturation.

The invention discloses a glycosyltransferase UGTZJ1 mutant. The amino acid sequence of the mutant is shown as any one of SEQ ID NO.2-4, and a gene for encoding the mutant and a preparation method ofthe mutant are also disclosed. The invention also discloses a vector, a cell and a genetically engineered bacterium containing the mutant encoding gene. The invention also discloses applications of the glycosyltransferase UGTZJ1 mutant, the gene for encoding the mutant, the vector and a cell line comprising the mutant encoding gene, particularly the genetically engineered bacterium containing theglycosyltransferase UGTZJ1 mutant, and the like in the aspect of catalyzing rebaudioside A to generate rebaudioside D. The yield of the rebaudioside D, which is generated by catalyzing the rebaudioside A through the genetically engineered bacterium containing the mutant, is increased by about 4 times compared with that of a wild type, and the yield of the rebaudioside D can reach 47.56 g/L under the optimal reaction condition.

The invention belongs to the field of electrochemical organic synthesis, and particularly relates to a device and method for device and method for coupled electro-catalytic hydrogen peroxide production and selective organic matter oxidation. According to the invention, the reaction device is composed of an anode chamber, a cathode chamber and an organic catalysis chamber, wherein the cathode chamber contains a catalyst for hydrogen peroxide production through oxygen reduction; the anode chamber contains a water oxidation or hydrogen oxidation catalyst; the organic catalysis chamber contains an organic matter oxidation catalyst; the anode chamber and the organic catalysis chamber are separated by a cation exchange membrane; and the cathode chamber and the organic catalysis chamber are separated by an anion exchange membrane. During working of the device, oxygen or air is introduced into the cathode chamber, hydrogen or water is introduced into the anode chamber, and an organic reactant is introduced into the organic catalysis chamber; and under an electrifying condition, a cathode is subjected to oxygen reduction to obtain OOH<->, an anode is subjected to water oxidation or hydroxide reaction to obtain H< + >, the H<+> enters the middle organic catalysis chamber through the corresponding anion and cation exchange membranes to form H2O2, and organic matters are further oxidized under the action of the catalyst. According to the invention, low-concentration hydrogen peroxide generated by oxygen reduction is directly used for oxidation of the organic matters, so problems in separation, concentration, storage and transportation cost and safety of H2O2 are avoided, and remarkable economic benefits are achieved. When the device is used for phenol oxidation, benzyl alcohol oxidation, furfuryl alcohol oxidation and cyclohexanone conversion, the selectivity of target products including benzenediol, benzaldehyde, furfural and cyclohexanone-oxime is greater than 98%, and corresponding total current efficiency is 21-49%.

The invention discloses a process for recycling and regenerating lithium cobalt oxide in a waste lithium cobalt oxide battery, which comprises the steps of firstly separating a collector and a cathodematerial in a positive pole plate of the lithium cobalt oxide battery by using an organic solvent N-methyl-2-pyrrolidinone (NMP), then removing residual impurities such as acetylene black and polyvinylidene fluoride (PVDF) in the cathode material by means of calcination, leaching cobalt and lithium elements in the cathode material by citric acid, and finally directly regenerating LiCoO2 from a leaching solution by adopting a sol-gel method, wherein citric acid plays a dual role of a leaching agent and a chelating agent in the process. According to the invention, a one-step technology route coupling an organic acid leaching method and a sol-gel method is adopted to recycle and regenerate LiCoO2, thereby avoiding the damage of organic acids to the environment, simplifying the recycling andregenerating process, reducing the cost, and achieving harmless treatment requirements while recycling the waste lithium cobalt oxide battery.

The invention relates to a hydrolysis method of astilbin. The method for preparing texifolin by hydrolyzing astilbin comprises the following steps: taking 48-52 parts by weight of astilbin, adding 300-1050 parts by volume of a 0.5-2.8 mol/L citric acid water solution while stirring, and carrying out hydrolysis at 85-135 DEG C for 1.2-3.8 hours to obtain a hydrolysate; filtering the hydrolysate while the hydrolysate is hot, concentrating the filtrate to 180-220 parts by volume, standing for at least 12 hours, crystallizing, filtering, and respectively collecting the filter cake and the filtrate, wherein the filter cake is a texifolin crude product; and recrystallizing the texifolin crude product to obtain the texifolin. The method avoids using the macroporous resin for separating and purifying the texifolin, thereby lowering the production cost and being beneficial to industrial production. Another hydrolysate-rhamnose of the astilbin is separated and purified, thereby enhancing the utilization ratio of the astilbin. The acid used by hydrolysis can be recovered and recycled, thereby avoiding the problems of waste of resources, environmental pollution and the like.

The invention discloses a synthetic method for pyrroline-3-formic ether compounds, and belongs to the technical field of organic synthesis. The technical key point of the synthetic method is disclosed in the following diagram. Compared with the prior art, the synthetic method has the following advantages: (1) one-pot cascade reaction is adopted so as to avoid a complex intermediate separation and purification process, reduce waste emission and lower environment burdens; (2) raw materials can be easily obtained; (3) reaction is carried out below 100 DEG C, conditions are moderate, and operation is simple; (4) the applicable range of a substrate is wide; (5) the economy of reacting atoms is high.

The invention discloses a method for efficient synthesis of difructose anhydride III. According to the method, saccharose is converted into inulin firstly by means of inulin sucrose without glycan separation, and then inulin is converted by means of inulin fructotransferase to generate functional disaccharide difructose anhydride III through synthesis. The technology is simple, efficiency is high, and the conversion rate of inulin for synthesis of difructose anhydride III can reach 40-54%. To obtain high-purity difructose anhydride III, micromolecule monosaccharide in reaction liquid is removed by means of yeast, and the finally obtained high-purity difructose anhydride III is easy to separate and purify and has broad market prospects.

The invention discloses a method for separating and purifying deoxynucleoside triphosphate, which comprises the following steps: when the temperature is below 4 DEG C, depositing deoxynucleoside triphosphate biosynthesized reaction solution directly with an organic solvent to obtain a solid mixture of the deoxynucleoside triphosphate, wherein the volume ratio of the deoxynucleoside triphosphate biosynthesized reaction solution to the organic solvent is between 1:1 and 1:25; when the temperature is below the 4 DEG C, dissolving the solid mixture in ultrapure water, adjusting the pH value to between 0.1 and 2 by using acidic aqueous solution, and using the organic solvent to perform deposition again to obtain a solid matter of the deoxynucleoside triphosphate; and dissolving the solid matter in the ultrapure water, adjusting the pH value to between 5 and 11 by using sodium hydroxide alkaline aqueous solution, and performing liquid nitrogen frozen and freeze-drying to obtain a sodium salt product of the deoxynucleoside triphosphate. The method has the advantages of quick separation, good purification effect, production cost reduction, water resource pollution reduction, process energy consumption reduction, and applicability to industrial production.

The invention discloses a synthesis method for preparing chiral polysubstituted 1,2-dihydropyridine as well as polysubstituted pyridine and chiral piperidine derived from chiral polysubstituted 1,2-dihydropyridine by using a "one-pot serial connection method". The method comprises the following step: by taking an imine compound and an aldehyde compound as raw materials, performing an asymmetric Mannich reaction, a Wittig reaction and an intramolecular ring-closing reaction in sequence, so as to synthesize a chiral 1,2-dihydropyridine compound with high three-dimensional selectivity. The product does not need to be purified, and a polysubstituted pyridine compound can be prepared through oxidation aromatization through further "one-pot serial connection", and a polysubstituted chiral piperidine compound can be also prepared through catalytic hydrogenation after separation and purification. The method starts from simple and easily obtained raw materials, separation and purification of anintermediate are avoided, and compounds of 1,2-dihydropyridine, polysubstituted pyridine and chiral piperidine are efficiently synthesized through simples steps of operation. Nitrogenous six-memberedring frameworks which are synthesized by using the method and disclosed by the invention are all common in many natural products and medicine molecules, and have great significances for acceleratingmedicine research and development.

The present invention discloses new 1,3-dihydroxy-3,7-dimethyl-6-octen-2-one synthesis method, which comprises racemic synthesis and enantioselective synthesis. According to the present invention, commercially available 6-methyl-5-hepten-2-one (CAS:110-93-0) is adopted as a starting material, two one-pot series connection reaction systems are adopted, simple operations are performed, the separation purification of the intermediate is effectively avoided, the high-yield racemic synthesis of the 1,3-dihydroxy-3,7-dimethyl-6-octen-2-one is achieved, and the asymmetric synthesis method for enantioselective synthesis of (R)-1,3-dihydroxy-3,7-dimethyl-6-octen-2-one and (S)-1,3-dihydroxy-3,7-dimethyl-6-octen-2-one is developed. The present invention further discloses an intermediate compound.

The invention discloses a preparation method of a lithium ion battery positive electrode composite material and a precursor thereof, and in particular relates to a novel method for preparing a high-purity low-cost binary or ternary precursor and preparing a high-performance lithium ion battery binary or ternary positive electrode composite material by utilizing the precursor, belonging to the technical field of new energy materials and the preparation thereof. The method comprises the following specific steps: (1) putting salt-type solid raw materials of two or three of nickel, cobalt and manganese with crystal water into a reactor, and heating the materials to the molten state; (2) introducing ammonia under the protection of inert gas, supplementing a small amount of water or no water according to the solubility of salts at different temperatures, stirring and reacting; (3) evaporating ammonium salt after full reaction, taking the solid out, and drying so as to get the amorphous binary or ternary positive electrode composite material precursor; and (4) mixing the precursor with lithium carbonate according to a certain ratio, and further preparing the lithium ion battery positive electrode composite material through a two-section sintering method. The precursor synthetic method is simple, sodium hydroxide is avoided from being used, separation and purification are not required, and the high-purity positive electrode composite material precursor which has no impurities basically can be obtained; furthermore, no industrial waste water is discharged, and the by-product ammonium salt can further generate economic benefit; and the positive electrode composite material prepared by the precursor has excellent performances, and is convenient for industrialization.

The invention discloses a method for synthesizing 3-acyl hydrogenated azepine compounds, and belongs to the technical field of organic synthesis. The method comprises the steps of: adopting a seven-membered cyclic amine compound and 2-oxo-2-aryl acetic acid as raw materials, and performing a one-pot serial reaction to obtain the 3-acyl hydrogenated azepine compound directly, and the method comprises the specific operation steps of: dissolving the seven-membered cyclic amine compound 1 and 2-oxo-2-aryl acetic acid 2 in an organic solvent, then adding a copper salt catalyst and an oxidizing agent, and performing heating to raise the temperature for a reaction to obtain the 3-acyl hydrogenated azepine compound 3. The method has the advantages of a convenient operation process, mild conditions, a wide application range of the substrates and a potential prospect suitable for industrial amplification.

The invention discloses a catalyst and a method for preparing an asymmetric substituted aryl compound or a terphenyl derivative by a one-pot tandem reaction under the catalysis of functionalized imidazole salt and palladium salt. The catalyst mainly comprises the functionalized imidazole salt and the palladium salt in a ratio of 1:2 to 6:1. The method comprises the following steps: using the catalyst to respectively carry out one-pot tandem reactions between Heck/Suzuki, Heck/Heck, and Heck/Sonagashira by using aryl halides or a derivative thereof as a substrate in organic solvent; and directly preparing the asymmetric substituted aryl compound because intermediate products need not to be separated. A prepared chlorinated biphenyl compound can also carry out a Suzuki or Buchwald-Hartwig reaction for preparing the terphenyl derivative and an amino biphenyl compound. The catalyst has simple preparation and extremely low consumption and can catalyze more than two different coupling reactions, thereby having high efficiency and low cost; and the one-pot tandem reaction method has simple and convenient operation and mild conditions, avoids pollution, reduces waste, obtains high-yield valuable products and can be widely applied to the fine chemistry industry, the pharmaceuticals industry, and the like.

The invention relates to a Baeyer-Villiger monooxygenase and an application of the Baeyer-Villiger monooxygenase in synthesis of briracetam. The Baeyer-Villiger monooxygenase is preferably selected from any one of polypeptides with an amino acid sequence as shown in SEQ ID No: 1, SEQ ID No: 2, SEQ ID No: 3, SEQ ID No: 4 or SEQ ID No: 5. Under the catalysis of the Baeyer-Villiger monooxygenase disclosed by the invention, (R)-4-propyl-dihydrofuran-2-ketone can be synthesized economically, efficiently and environmentally friendly, and on the basis, a Briracetam bulk drug with high optical purity can be prepared through a one-step reaction. The route for preparing the briracetam provided by the invention avoids chiral resolution and tedious separation and purification used in the traditional process, is suitable for industrial production, and has a remarkable cost advantage.