79results about How to "High separation yield" patented technology

The invention provides a method for preparing 2,5-diformyl furan by catalytic oxidation of 5-hydroxy methyl furfural. The method comprises the following steps: taking air or oxygen as an oxygen source, taking a mixture of inorganic vanadium oxides, 2,2,6,6-4-pipecolate-oxygen radicals and derivatives and nitrites of the 2,2,6,6-4-pipecolate-oxygen radicals as a compound catalyst system, and oxidizing the 5-hydroxy methyl furfural into the 2,5-diformyl furan at a temperature of between 50 and 120 DEG C. The method has the advantages of high oxidizing efficiency, few byproducts, mild reaction conditions, easy separation and purification of products and quite high practicability.

The invention discloses a method for preparing epoxy chloropropane with the oxidation of chloropropene. The chloropropene, a solvent and fine particles of titanium silicate molecular sieve catalyst are put into a reaction pot and a hydrogen dioxide solution is added at 10 DEG C to 80 DEG C. The method is characterized in that a reaction is carried out under a subacidity condition and after the reaction, materials pass through an intermediate tank for oil-water dissociation to be divided into oil phase and water phase; the oil phase is sent into a rectifying tower for separating the chloropropene and ECH. After the water phase is filtered, a catalyst filter cake is washed by the solvent, regenerated or applied to an epoxidation reaction after being directly beat with the solvent. The ECH is extracted from an aqueous layer after filtration by the chloropropene. An extracted oil layer and an oil layer obtained from the separation of a reaction solution are combined and rectified, or the extracted oil layer is applied to the epoxidation reaction; water left from the extraction is rectified for recycling methanol and applied to the preparation of catalysts; and the method has simple procedures, small consumption amount of solvents, high separation yield of reaction products and easy realization of industrialization.

The invention discloses a method for preparing oligofuran dioctyl phthalate ester by directly esterifying and polymerizing. The method is characterized by comprising the following steps of: under the action of a compound catalyst, undergoing esterification and polymerization reactions on 2,5-furan dioctyl phthalate and low-carbon diatomic alcohol serving as raw materials at the temperature of 130-280 DEG C under the pressure of 2-15 mmHg for 1.5-16 hours; removing excessive low-carbon diatomic alcohol and other impurities by using a vacuum distillation or azeotropic distillation method; and purifying a polymer product with a dissolving-precipitating technology to obtain a high-quality oligofuran dioctyl phthalate ester product. The method has the advantages of high product yield, easinessin separating the product and good application prospect.

The present invention relates to a nitride semiconductor substrate such as gallium nitride substrate and a method for manufacturing the same. The present invention forms a plurality of trenches on a lower surface of a base substrate that are configured to absorb or reduce stresses applied larger when growing a nitride semiconductor film on the base substrate from a central portion of the base substrate towards a peripheral portion. That is, the present invention forms the trenches on the lower surface of the base substrate such that pitches get smaller or widths or depths get larger from the central portion of the base substrate towards the peripheral portion.

The invention relates to a method for preparing furan derivatives through biomass catalytic conversion. The method is characterized in that glucose, sucrose, cellobiose, cellulose, hemicellulose, lignocellulose, and the like are adopted as raw materials; under the effect of a catalyst, the raw materials are subjected to hydrolysis, isomerization, and dehydration reactions in a polar organic solvent, such that furan derivatives such as 5-hydroxymethylfurfural, 5-alkoxymethylfurfural, and furan acetals are obtained. The method has high raw material utilization rate. The system has the advantages of easy separation and easy purification.

Production of gabapentin is carried out by 3,3-pentylidene butyrolactam as initial raw material, hydrolyzing to obtain gabapentin salt, converting it into gabapentin hydrate and elutriating out gabapentin from alcohol solvent, neutralizing while adsorbing and decoluring residual hydrate by active carbon and siliceous earth, controlling pH to 8-8.5 and recovering mother-liquid. It is safe and convenient, has short period, less consumption and higher recovery rate. It can be used for industrial production.

The invention discloses a preparation method for caprolactone. The method comprises the following steps: with supersaturated aliphatic acid and cyclohexanone as reaction raw materials, carrying out a reaction at 40 to 50 DEG C for 1 to 2 h so as to obtain a crude caprolactone solution; then carrying out negative pressure distillation so as to remove a solvent and incompletely reacted raw materials; and cooling the residual solution and carrying out crystallization, filtering and separation so as to obtain caprolactone. The method has the advantages of simple operation, high separation yield of caprolactone, small loss, capacity of realizing continuous feeding in the whole separation process from the crude caprolactone solution to the caprolactone product and applicability to industrial production.

The invention provides a method for preparing imino ether by virtue of catalytic conversion of aromatic aldehyde. The method is characterized in that one or two of oxygen gas and air is/are taken as an oxygen source, one or two of ammonia water, ammonia gas, urea and ammonium salt is/are taken as a nitrogen source, and alcohol with low boiling point is taken as a solvent, so that aromatic aldehyde is subjected to an ammoxidation reaction in the presence of a catalyst, and nitrile which is generated in situ and alcohol are subjected to an addition reaction so as to obtain imino ether. The method has the advantages that the raw material utilization ratio is high, the catalyst is easy to recover and recycle, and the separation, purification and derivative conversion of target products are easy.

The invention relates to forcipate thioacid amide ligand of sulfo-2, 6-pyridine diformamide framework and a complex compound thereof, the constitutional formula thereof is as above, wherein, R in the formula is C2 to C8 alkyl, and phenyl-substituted alkyl or phenyl-substituted by alkoxy; and M is nickel, palladium or platinum. The ligand provided by the invention is non-phospine ligand and keeps stable against air and water, and lone pair electrons on nitrogen in the thioacid amide can adjust the electric property of sulfur, substitutional group on nitrogen can adjust the electron and the spatial configuration of the whole ligand; the ligand has the advantages of convenient compound, high total yield, and numerous compound. The complex compound provided by the invention has the advantages of high stability owing to the special forcipate structure, high catalytic activity during the catalytic reaction, wide application range, good selectivity and mild reaction condition, and is widely applicable to the cross coupled reaction of the transition metal catalyze, such as the Heck reaction and the like.

A biomass based polyester preparation method is as follows: biomass based monomer 2, 5-dihydroxy methyl furan and a dibasic acid are used as raw materials for esterification prepolymerization for reaction for 0.5-10h in the presence of a catalyst at 90-300 DEG C under the protection of nitrogen; ester exchange condensation is performed at 150-350 DEG C under the condition of 1-10mmHg vacuum, and the reaction is performed for 0.1-15h; a dissolution-precipitation method is used for purification and removing of impurities and unreacted monomers and oligomers to obtain the biomass based polyester product. The biomass based polyester product prepared by the preparation method is high in yield, easy in product separation, and environmental friendly, and has good application prospects.

The invention relates to a preparation method of a biomass-based phenolic resin. According to the invention, a biomass monomer 2,5-diformyl furan and phenol are adopted as raw materials; under the catalyzing of alkali, a temperature of 30-200 DEG C, and nitrogen gas protection, the raw materials are subjected to a addition and condensation reactions for 1-10h; and water and other impurities in the reaction system are removed with a vacuum distillation method, such that a novel phenolic resin high-quality product with 2,5-diformyl furan for substituting formaldehyde is obtained. With the method, the prepared product has the advantages of high yield, easy separation, and environment-friendliness. The method has good application prospect.

The invention provides a synthetic method of tazobactam diphenylmethyl ester. The synthetic method comprises the following step: under the action of a catalyst, a compound A and hydrogen peroxide aresubjected to an oxidation reaction to obtain the tazobactam diphenylmethyl ester (the synthetic route is as follows). In the synthetic method provided by the application, the hydrogen peroxide is usedas an oxidant, and the only by-product is water, so that on the one hand, the generation of waste solids can be greatly reduced, the amount of three wastes is greatly reduced, and the environment-friendly performance of the process is improved, and on the other hand, since the reaction by-product is only water, the synthetic method is adopted to facilitate improvement of the purity of a tazobactam diphenylmethyl ester product. Besides, the synthetic method has the advantages that the purity of the product can reach 98%, the post-treatment operation is simple, the separation yield is as high as 95.7%, and amplified production is easy.

The invention provides a system and method for separating and refining a xylylene diisocyanate product. The system comprises a desolventizing column, a de-heavy column, a stabilizer mixing device anda product refining column, wherein a to-be-treated raw material enters the desolventizing column through a feeding port of the desolventizing column; a column bottom material outlet of the desolventizing column is connected with a material inlet of the de-heavy column; a middle material outlet of the de-heavy column is connected with a feeding port of the stabilizer mixing device; a material outlet of the stabilizer mixing device is connected with the product refining column; and a material outlet is formed in the middle of the product refining column. The system and method are scientific in design, reasonable in structure, energy-saving, low in production cost, reliable in production quality, simple in process, easy to operate, high in safety, low in energy consumption, high in extractedproduct purity, high in product separation yield and less in XDI polymerization.