95 results about "Diethyl succinate" patented technology

The invention discloses red date brandy and a production process thereof. The red date brandy is prepared by using red dates as raw materials through the processes of separating, cleaning, roasting, smoke curing, extruding, soaking, treating with steam, pulping, protecting colors, carrying out ultrasonic enzymolysis, regulating constituents, sterilizing, fermenting, distilling, adsorbing, storing, blending, ageing, and the like, wherein the processes of roasting and smoke curing with peat are used for increasing fragrance and the contents of phenols; the processes of extruding and soaking arebeneficial to extracting date juice; the composite method of treating with steam, protecting the color and carrying out ultrasonic enzymolysis is used for improving the juice yield and the date juicequality; the processes of supplementing a proper quantity of date juice and adding flavor-producing yeast in a later stage mainly aim to generate flavor constituents such as ethyl acetate, isoamyl acetate, diethyl succinate, and the like; the method for distilling for three times is used for collecting flavor constituents of aldehydes, esters, high-grade alcohols, and the like to obtain a high-quality distilled liquor; the adsorbing treatment is used for removing impurities with poor flavors and greatly improving the fragrance and the flavor of the wine; and through storing, blending and ageing, the wine is more mature, fine, smooth and soft. The obtained red date brandy has the advantages of rich and mellow mouthfeel, harmonious red date fruit fragrance, aged oak fragrance, elegant and strong bouquet and pure and mild as well as fine and smooth mouthfeel.

The invention relates to a preparation method of 2,3-diisopropyl succinate and ester compound thereof, which comprises the steps of: carrying out an oxidative coupling reaction of a 3-methyl-2-cyano butyrate compound for preparing a 2,3-diisopropyl-2.3-dicyano-diethyl succinate compound; carrying out a hydrolysis reaction and a decarboxylation reaction for preparing the 2,3-diisopropyl succinate;and further esterifying for preparing the 2,3-diisopropyl diethyl succinate compound. An intermediate of the 2,3-diisopropyl-2.3-dicyano-diethyl succinate compound and the preparation method thereof are beneficial to commercially producing 2,3-diisopropyl succinic ester which is an internal electron donor compound used capable of being used for preparing a Ziegler-Natta polypropylene catalyst. The invention can be used for the technical field of petrochemical polypropylene.

The invention relates to a method for preparing dimethyl succinate, which comprises the following steps that: (1) dehydration and decontamination: methanol and alkali-earth metal oxide are mixed, dehydrated and decontaminated; (2) separation of solid and liquid; (3) monoesterification reaction: maleic anhydride is added in the liquid-phase material which is obtained in the previous step; (4) vacuum distillation; (5) 2-esterification reaction; (6) evaporation; (7) mixing of oil and water; (8) separation of oil and water; (9) re-eesterification; (10) evaporation; (11) mixing of oil and water; (12)separation of oil and water; (13) electrochemical reduction: hydrogen is introduced to reduce dimethyl maleate to dimethyl succinate; (14) cooling and crystallization; (15) separation of solid and liquid: solid material enters the next step; (6) re-crystallization and separation: the product dimethyl succinate is obtained. The method is simple, and has reasonable process, low preparation cost, high product purity and good quality.

The invention provides a synthetic method of plant growth regulator trinexapac-ethyl intermediate 3-carbethoxy-5-oxo-cyclohexane-1-enol cyclopropanecarboxylate. The synthetic method comprises the following steps: (1) carrying out annulation reaction on 2-acetonyl-1,4-diethyl succinate and organic alkaline at the temperature of 20-120 DEG C for 0.5-5 hours in a non-polarity organic solvent to obtain 3,5-cyclohexanedione-1-ethyl formate; and (2) adding organic amine and cyclopropanecarboxylic acid chloride, and carrying out acylation reaction at the temperature of minus 5-50 DEG C, so as to obtain 3-ethoxycarbonyl-5-oxo-cyclohexane-1-enol cyclopropanecarboxylate in the presence of micromolecular alcohol, ether, ketone and nitrile the carbon atoms of which are below C8 and are used as additives. According to the method, special additives are added before acylation so that cyclopropanecarboxylic acid chloride can directly react with intermediate-state 3-ethoxycarbonyl-5-oxo-cyclohexane-1-enol sodium salt to obtain the trinexapac-ethyl precursor 3-ethoxycarbonyl-5-oxo-cyclohexane-1-enol cyclopropanecarboxylate, thereby shortening reaction time, simplifying synthesis process and improving yield; and the product is directly rearranged without purification so as to obtain the final product trinexapac-ethyl.

The invention provides a preparation method of dimethyl succinate. The method comprises the steps of mixing maleic anhydride, an alcohol compound, carbon dioxide, hydrogen and a hydrogenation catalyst and conducting esterification hydrogenation reaction to obtain the dimethyl succinate. According to the method, the maleic anhydride, the alcohol compound and hydrogen serve as raw materials, the carbon dioxide serves as a solvent and an acid catalyst, under catalysis of the hydrogenation catalyst, the esterification hydrogenation reaction is conducted, and the dimethyl succinate is obtained. The carbon dioxide serves as the solvent of the esterification hydrogenation reaction and the acid catalyst, high catalytic activity is achieved, and the reaction rate is improved; the carbon dioxide and water generated in the reaction process can form acid, and an obtained product has certain solubility in the carbon dioxide, so that the reaction can be conducted in a positive direction, and the conversion rate and the production rate of the dimethyl succinate are improved. Experimental results show that the yield rate of the obtained dimethyl succinate exceeds 99%.

The invention provides a mixed solvent used for dissolving nitrated cellulose. The mixed solvent contains 1-50wt% of diethyl succinate, 10-60wt% of acetyl tributyl citrate, 10-80wt% of diethylene glycol butyl ether acetate and 1-40wt% of glycerol triacetate. The invention also provides a water-soluble nitrated cellulose product and a water-soluble nitrated cellulose product prepared by the mixed solvent provided by the invention. The nitrated cellulose product prepared by the mixed solvent is little in smell and low in toxicity, has good volatilization grade, and greatly improves the production environment of leather processing enterprises and alleviates the harm to the body health of workers on the basis of keeping the performances of the nitrated cellulose products.

The invention relates to a descaling agent for water scale of condensing equipment and a descaling method. The descaling agent comprises the following materials in percentage by weight: 15%-30% of dissolving agents, 2%-5% of permeating agents, 1%-5% of corrosion inhibitors, 10%-30% of cosolvents, 20%-30% of purified water and the balance of ethanol, wherein the dissolving agents are selected from oxalic acid, citric acid, ascorbic acid, salicylic acid and glacial acetic acid; the permeating agents are selected from diethyl succinate, butyl cellusolve and sulfonated dioctyl succinate sodium salt; the corrosion inhibitors are selected from urotropine, aniline and diethyl thiourea or rodine; the cosolvents are selected from para-benzoic acid, urea, cyclohexanone, acetamide and sodium salicylate. The descaling agent disclosed by the invention is obtained by blending the raw materials, has high descaling capacity and higher descaling speed by utilizing combined effect, is less in corrosion on equipment and low in price and can save a large amount of cleaning expense, enhance the equipment operation level, the energy utilization level and the production efficiency and greatly reduce the product production cost.

The invention relates to a catalyst that is used for preparing 1,4-butanediol by diethyl succinate hydrogenation and a preparation method of the catalyst. In the total weight of the catalyst, cupric oxide accounts for 30 to 60 weight percent (Wt), zinc oxide accounts for 20 to 50 weight percent (Wt), and titanium oxide accounts for 5 to 20 weight percent (Wt). In the preparation, the dissoluble salts of copper, zinc and titanium are mixed according to the proportions thereof in the total weight of the catalyst and dissolved in deionized water, thus preparing a metallic ion mixture solution, under water-bath heated agitation, the metallic ion mixture solution and a precipitator are drop-added in current flow, the pH value of the solution is controlled between 7 and 8, the solution is agitated at constant temperature for 1 to 3 hours, temperature is raised to 70 to 80 DEG C for aging for 2 to 20 hours, precipitate is filtered, the precursor precipitate is rinsed by deionized water so as to remove impurity ions, and then the precipitate is dried at the temperature of 110 to 120 DEG C for 8 to 12 hours and baked in a muffle furnace at the temperature of 350 to 550 DEG C for 3 to 5 hours. The invention has the advantages that the provided catalyst has standardized pore structure, higher specific surface, higher activity, good selectivity, and the production and recycling without environmental pollution.

The invention discloses a method for preparing diethyl succinate catalyzed by a pyridine ionic liquid. The method is to mix succinic acid and ethanol with a molar ratio of 1:3, add Brφnsted acidic pyridine ionic liquid catalyst, and the catalyst The amount is 5-8% of the mass of succinic acid, the reaction temperature is 60-70°C, the reaction time is 2-3h, and the catalyst and product are separated by ether extraction. The pyridine ionic liquid used in the present invention has high catalytic activity, good selectivity, low price, and stable properties, and can be reused after simple rotary evaporation and water removal treatment, which not only realizes green synthesis, but also reduces manufacturing costs and improves economic efficiency. benefit. The invention can be used for synthesizing butanediol diethyl ester and is suitable for large-scale industrial production.

The invention discloses a preparation method of poly(butylene succinate). The preparation method comprises the following steps: (1), under catalytic action of lipase, polymerizing an acyl donor and 1,4-butanediol through liquor to obtain a prepolymer, wherein the acryl donor is at least one of succinic acid, dimethyl succinate and diethyl succinate; (2), under the catalytic action of the lipase, polymerizing the prepolymer by virtue of a main body to obtain poly(butylene succinate). The invention provides the preparation method of poly(butylene succinate) with high molecular weight. Compared with the existing technology of synthesizing polyesters in an enzymatic manner, under the condition that material ingredients are the same, the method disclosed by the invention can be used for greatly reducing consumption of energy and dosage of the organic solvent in the processing process, and improving the molecular weight and material performance of a product. Moreover, the method can be used for overcoming a bottleneck of short-chain aliphatic monomer polymerization in an enzymatic manner, obtaining a high molecular product which can be put into practical application; meanwhile, the production cost is lowered by virtue of normal-pressure polymerization, and a basis is provided for industrially producing the polyesters by virtue of an enzyme process.

The invention relates to a preparing method of 3-fluoroacetone acid. Diethyl oxalate and fluoro ethyl acetate are adopted as raw materials, NaH is adopted as a strong base catalyst to conduct an ester condensation reaction to obtain 2-fluo-3-oxo diethyl succinate, wherein the yield rate is 84.6%, and the gas phase chromatographic detection purity is 99.9%. 2-fluo-3-oxo diethyl succinate is put into an acid solution, and then through hydrolysis and decarboxylation reactions, and then through distillation and water removal, a coarse product is obtained, and finally through a sublimation method, 3-fluoroacetone acid is obtained, the yield rate is 85.4%, the liquid phase chromatographic detection purity is 99.9%, and the total yield through the two steps is 72%. The reaction technology is simple in condition, reactions are all conventional reactions under the normal pressure, the operation is simple and convenient, the raw materials are easy to obtain, and the product cost is low.

The invention discloses a fibroin shampoo and a preparation method thereof. The shampoo comprises the following components: guar gum, octadecyl trimethyl ammonium chloride, hydroxyethyl cellulose, lecithin, glycerol, propylene glycol, fibroin, vitamin E acetate, essence, diethyl succinate, menthol and deionized water. The preparation method comprises the steps of adding the guar gum, hydroxyethyl cellulose, lecithin, propylene glycol, fibroin, vitamin E acetate, essence, diethyl succinate and menthol into a reactor, adding 30-40 weight parts of deionized water, stirring and mixing uniformly, and then heating and stirring to obtain a mixture I; adding the octadecyl trimethyl ammonium chloride and the glycerol into the mixture I, heating and stirring under vacuum, then adding the remaining deionized water, continuously stirring the mixture, and homogenizing with a high pressure homogenizer to obtain the fibroin shampoo. The shampoo has good stability and hair washing and nourishing performance.

The invention discloses a method for determining dimethyl sulfate and diethyl sulfate in electronic and electric products. The method comprises the following steps: adding a certain amount of acetone into a prepared sample, carrying out ultrasonic extraction to obtain the target compounds, deriving the target compounds with p-nitrophenol under alkaline conditions, extracting the derivation products with diethyl ether, and separating and detecting the ethyl ether extraction solution with a high performance liquid chromatography (HPLC) system. The chromatographic column uses an octadecyl bonded silica gel as the filler; the detector is a diode array detector; the mobile phase is a mixed solvent composed of 40-60 vol% of methanol and 60-40 vol% of water; the detection wavelength is 305nm; the column temperature is 40-60 DEG C; and the sample injection volume is 5-20 muL. After the systemic comparative studies, the invention establishes an HPLC method for determining contents of dimethyl sulfate and diethyl sulfate in electronic and electric products for the first time; and the method has the technical characteristics of favorable separating effect, high determination accuracy, high sensitivity, high specificity, simple and quick analysis and the like.

The invention provides a method used for preparing diethyl sulfate. According to the method, a mixed solution containing ethyl hydrogen sulfate and/or diethyl sulfate is delivered through reaction distillation surface at a certain temperature, and at the same time, reduced pressure distillation is carried out, so that diethyl sulfate in the mixed solution and generated on the reaction distillation surface is separated rapidly, waste sulfuric acid in the mixed solution and generated on the reaction distillation surface is collected in a waste liquid collector, and ethanol is collected in a tail gas collector. Recycling of waste sulfuric acid and collected ethanol can be realized; the method is low in cost; and no waste acid is discharged.

The invention discloses a preparation method of mitiglinide calcium. The preparation method comprises the following steps: (I) by taking diethyl succinate and benzaldehyde as raw materials, carrying out a reaction in a sodium ethoxide solution, and then, under the action of a multiphase asymmetric catalyst Ru-SBA-16, carrying out asymmetric hydrogenation to obtain a (S)-2-benzylsuccinic acid; (II) reacting the (S)-2-benzylsuccinic acid with perhydro-isoindole so as to generate mitiglinide; and (III) complexing the mitiglinide and calcium chloride so as to obtain a target compound mitiglinide calcium. According to the method, the reaction steps can be reduced, the reaction time can be shortened, and the chiral purity of mitiglinide calcium can be improved.

The invention discloses an aluminium alloy surface acid degreasing agent which is characterized by comprising the following components in part by weight: 25 to 35 parts of concentrated sulphuric acid, 3 to 5 parts of sodium dodecyl sulfate, 0.1 to 2 parts of diethyl succinate sodium sulfonate and 1,000 parts of water. The aluminium alloy surface acid degreasing agent can be used for an acid pretreatment tank of products such as an aluminium section, an aluminium alloy and the like, has strong effects of removing oil stain and removing oxide, has slight corrosion to an aluminium base and has good gloss. The aluminium alloy surface acid degreasing agent can be operated at normal temperature, energy is saved and the acid mist overflowing and the acid pickle discharge are reduced, so that the damage to human bodies and the pollution to the environment are reduced in the production link.

The invention discloses a method for preparing a 2-(1-methylalkyl) succinic acid. The method comprises the following steps: (1) producing 1,1,2-ethane tricarboxylic acid triethyl ester from ethyl bromoacetate and diethyl malonate by condensation reaction; (2) producing 3-methyl alkane-1,1,2-tricarboxylic acid triethyl ester from the 1,1,2-ethane tricarboxylic acid triethyl ester and 2-bromoalkane; (3) mixing 3-methyl alkane-1,1,2-tricarboxylic acid triethyl ester with LiCl/H2O, heating and carrying out decarboxylation to obtain 2-(1-methylalkyl) diethyl succinate; and (4) hydrolyzing the 2-(1-methylalkyl) diethyl succinate in a strong alkali solution to obtain the 2-(1-methylalkyl) succinic acid. The method is wide in reaction material source, low in price, mild in reaction condition, complete in reaction, and less in side reaction, and a 2-(1-methylalkyl) succinic acid homologous compound of which the alkyl carbon chain is 3-16 carbons in length can be prepared.