239 results about "Acetaldehyde" patented technology

The invention discloses a copper-based catalyst for preparing acetaldehyde through ethanol dehydrogenation as well as a preparation method and application of the copper-based catalyst. The preparation method comprises the following steps: S1, carrying out alkalization treatment on protic mordenite in a strong alkali solution to increase the number of surface hydroxyl groups of the protic mordenite; and S2, adding the mordenite obtained in the step S1 into a copper salt solution to load copper ions, and then sequentially carrying out low-temperature drying shaping and medium-temperature activation stages to obtain the copper-based catalyst with networked Cu-OH-Si-O bonds on the surface. Through the synergistic effect of alkali liquor regulation and control and staged oxygen roasting, the dispersity and stability of a Cu active center in the catalyst are improved, the acetaldehyde selectivity of the reaction of preparing acetaldehyde through ethanol dehydrogenation is also improved, and side reactions are inhibited. Carrying out heat treatment regeneration on the inactivated copper-based catalyst in an oxygen-containing atmosphere; and after regeneration, the networked Cu-OH-Si-O bond on the surface of the copper-based catalyst is reconstructed.

Disclosed herein is a method for converting ethanol to 1,3-butadiene, wherein the method utilizes H2 produced during a first step of the method for subsequent conversions involved in the method. In particular aspects, H2 produced from converting ethanol to acetaldehyde is used to promote the conversion of the acetaldehyde to 1,3-butadiene. The H2 promotes enhanced catalyst stability, as well as enhanced selectivity and yields of the 1,3-butadiene product. In particular aspects, the method comprises two steps to produce the 1,3-butadiene from the ethanol and H2 produced from a first step facilitates enhanced selectivities and yields for the second step.

This application discloses an acetaldehyde recovery device and method in the production of 1,3-butanediol, belonging to the field of fine chemicals. The device includes: a feed pump, a preheater, a distillation column, a falling film reboiler, a bottom circulating pump, a bottom cooler, a top primary condenser, a reflux ratio distributor, a top secondary condenser, a top product tank, a top transfer tank, a bottom product tank, a bottom transfer tank, a vacuum condenser, a vacuum pump inlet separator, a high vacuum unit, and a vacuum pump outlet separator. The horizontal condenser is directly installed at the top of the distillation column, giving it advantages such as simple structure, convenient operation, low pipeline loss, and high vacuum. A method for acetaldehyde recovery in the production of 1,3-butanediol using this device is also disclosed. Compared to existing technologies, this invention uses falling film evaporation combined with vacuum deep cooling, which avoids the thermal decomposition of 3-hydroxybutyraldehyde and achieves low-temperature, high-efficiency acetaldehyde recovery. It is suitable for continuous production.

The invention relates to polyfurandicarboxylic acid glycol ester resin as well as a preparation method and application thereof, and belongs to the technical field of organic high-molecular compounds. The preparation method of the polyethylene furandicarboxylate resin provided by the invention comprises the following steps: S1, mixing 2, 5-furandicarboxylic acid, ethylene glycol, a catalyst and an inhibitor, and carrying out esterification reaction to obtain an ester; and S2, carrying out low-pressure condensation polymerization on the ester obtained in the step S1 to obtain the polyethylene furandicarboxylate resin, the inhibitor is ethylene carbonate; according to the GB / T14571.2-2018 standard, based on the chromatographic purity of the ethylene glycol, the chromatographic peak area of the inhibitor in the mixture of the ethylene glycol and the inhibitor is 0.05%-0.6% of the sum of the chromatographic peak area of the inhibitor and the chromatographic peak area of the ethylene glycol. The preparation method can effectively reduce the content of acetaldehyde in the polyethylene furandicarboxylate resin.

The invention discloses Leishan fish sauce sour essence as well as a preparation method and application thereof. The leishan fish sauce acid essence is prepared from ethyl acetate, absolute ethyl alcohol, ethyl isovalerate, ethyl hexanoate, isoamyl alcohol, furfuryl alcohol, ethyl lactate, ethyl caprylate, acetic acid, diethyl succinate, methyl salicylate, ethyl benzoate, ethyl laurate, hexanoic acid, phenethyl alcohol, 4-methyl guaiacol, ethyl myristate, ethyl palmitate, ethyl oleate, capsicum oleoresin, ethyl phenylacetate and ginger oil. And lactic acid, glycerol triacetate, ocimene, ethyl isovalerate, ethyl butyrate, anethole and phenylacetaldehyde. The Leishan fish sauce sour essence disclosed by the invention is soft and harmonious in overall fragrance, natural and vivid, still has stable flavor characteristics at high temperature, can make up the problem of flavor deficiency in sour soup products, realizes accurate reproduction and controllable release of composite fragrance, improves the standardization level of products, and effectively improves the preference degree of consumers.

The invention relates to pediococcus acidilactici b1274 and application thereof, and belongs to the technical field of beneficial bacterium application. The pediococcus acidilactici b1274 is preserved in the China Center for Type Culture Collection on September 24, 2025, the preservation number is CCTCC M 20252094, and the pediococcus acidilactici b1274 is obtained by separation and purification from distiller's yeast. The pediococcus acidilactici can be used for preparing microbial enhanced distiller's yeast, is applied to brewing of fen-flavor liquor, and can improve the content of ethyl acetate, ethyl lactate and total acid in the liquor and reduce the content of acetaldehyde at the same time. Compared with a production control group, the content of ethyl acetate is increased by 50.0%, the content of ethyl lactate is increased by 8.1%, the total acid is increased by 46.4%, the acetaldehyde is reduced by 48.4%, the brewed white spirit shows the style of faint scent, purity, mellowness, fullness, softness, sweetness, freshness, long aftertaste and mellow and prominent acid ester taste, and a safe and reliable functional strain and a technical scheme are provided for improving the quality of the fen-flavor white spirit.

A mosquito repellent composition and a preparation method therefor and a use thereof, and a product having the composition, relating to the technical field of mosquito repelling. The mosquito repellent composition comprises in percentage by weight: 0.1-40% of a mosquito repellent active ingredient, 1-10% of an emulsifier, 3-8% of an antifreeze agent, 0.1-3% of a thickener, 0.1-2% of a defoamer, and the balance being water, or 0.1-40% of a mosquito repellent active ingredient, 1-10% of an emulsifier, 1-10% of a capsule wall material, 0.1-0.5% of a pH regulator, 3-8% of an antifreeze agent, 0.1-3% of a thickener, 0.1-2% of a defoamer, and the balance being water, wherein the mosquito repellent active ingredient comprises α-ethylidene-phenylacetaldehyde, or a tautomer or cis-trans isomer thereof. Compared with an α-ethylidene-phenylacetaldehyde technical material, the mosquito repellent composition has greatly improved thermal storage stability and a longer-lasting mosquito repellent effect. Compared with emulsions in water and capsule suspensions prepared by other formulas, the emulsion stability after thermal storage is greatly improved.

The application relates to the technical field of polymer material processing and molding, and discloses a temperature gradient control method for melting and plasticizing of food packaging PET bottle blanks. The method aims to solve the problems of static temperature control, poor melt homogeneity and weak process adaptability in the traditional plasticizing process. The method comprises the following steps: constructing an axial partition temperature setting model, dividing a solid conveying section, a melting transition section and a melt homogenization section and setting a reference temperature interval; deploying a distributed temperature sensing array to collect temperatures at key positions in real time; establishing a melt thermal state prediction model based on a non-Newtonian fluid heat conduction equation; dynamically regulating and controlling heating and cooling through a PID compound algorithm to realize closed-loop control of axial gradient and radial uniformity; and combining a process database to perform adaptive parameter correction. The application can significantly improve temperature control precision and melt homogeneity, enhance adaptability to raw material changes and high-speed production, effectively reduce bottle blank internal stress, wall thickness deviation and acetaldehyde content, and guarantee product quality and food safety.

Provided is a process for producing acrylic acid, wherein the process comprises a first step and a second step in which a first absorbent is added to a reaction product of a bio-material and cooled to separate a first low-boiling-point material including acetaldehyde (ACHO) and a first high-boiling-point material including acrylic acid (AA). The process is capable of producing high-purity acrylic acid at high yield, and acetaldehyde is produced as by-product along with the reaction product of the bio-material. The process includes separating the acetaldehyde produced as by-product into a high-purity product at high yield.

The application discloses a brewing method for improving the quality of a light-flavor type base liquor by using medicinal and edible Chinese herbal medicines, four kinds of medicinal and edible Chinese herbal medicines, namely, clove, mulberry leaf, lophatherum gracile and osmanthus, are adopted, and the suitable adding link and adding proportion of the medicinal and edible Chinese herbal medicines in the brewing process are determined. Compared with the traditional brewing process, the content of fusel oil (defect component) in the base liquor produced by the application is reduced by 13.89%, the content of ethyl acetate (important flavor component) is increased by 71.14%, the content of beta-damascenone is increased by 240.36%, and the contents of defect components such as acetaldehyde, methanol, n-propanol and fusel oil are all significantly reduced.

The invention belongs to the field of photocatalysis, and particularly discloses a perovskite composite photocatalyst for photocatalytic ethanol dehydrogenation and application. The composite photocatalyst takes a CdS nanorod as a carrier, a Cs2AgBiBr6 double perovskite active component formed by CsBr, AgBr and BiBr3 precursors is loaded on the surface of the CdS nanorod through a vacuum in-situ growth method, and a Pt, Rh or Ni metal cocatalyst can be further loaded. The method comprises the following steps: dispersing a CdS nanorod and a perovskite precursor in a mixed organic solvent, carrying out vacuum freezing-air exhaust circulation treatment, and removing the solvent under a heating condition to prepare the composite photocatalyst. When the photocatalyst is used for an ethanol photocatalytic dehydrogenation reaction under an anaerobic condition, hydrogen, acetaldehyde and acetal can be efficiently generated under the irradiation of visible light. According to the method, the photo-generated charge separation efficiency and the reaction stability are remarkably improved, and a new way is provided for ethanol high-valued conversion.

The application discloses a kind of tetrameric acetaldehyde granules and preparation method thereof, which have both attractivity and waterproofness.The tetrameric acetaldehyde is mixed with fillers, filler attractants and binders after adding water, and then granulated.The prepared granules are coated with a coating agent containing polyethylene glycol monomethacrylate or sodium lignosulfonate, and then sprayed, coated and dried to obtain the tetrameric acetaldehyde granules with both attractivity and waterproofness.The test results show that the tetrameric acetaldehyde granules have strong attractivity to golden apple snails, and the tetrameric acetaldehyde in the granules will not be quickly precipitated into water after being contacted with water, so that the tetrameric acetaldehyde can be used for long-term to kill golden apple snails, which is conducive to the efficient prevention and control of golden apple snails.

This invention discloses a mutant of glycolaldehyde synthase and its application in improving the thermostability of glycolaldehyde synthase, belonging to the field of biocatalysis application technology. The glycolaldehyde synthase mutant disclosed in this invention, based on the amino acid sequence shown in SEQ ID NO.1, contains the following mutations: A381P / E509F, A381P / K290P, A381P, S61A, A381P / K290P / E509F, A381P / C49A, A381P / T100V, A381P / S61A, or A381P / K290P / S61A. This mutant protein can catalyze the preparation of hydroxyacetaldehyde (glycoaldehyde) from formaldehyde. The mutant protein of this invention also improves the catalytic efficiency of the formaldehyde-to-glycoaldehyde conversion. Due to the improved thermostability, it is beneficial for continuous catalysis in actual industrial reactions, thus the mutant shows good prospects for industrial applications.

The application relates to a preparation method of 4-chloropyrrolopyrimidine, in particular to a four-step high-yield synthesis of 4-chloropyrrolopyrimidine by taking diethyl malonate and bromoacetaldehyde diethyl acetal as raw materials, through substitution reaction, then ring closure reaction with formamidine acetate, ring closure reaction under acidic conditions, and then chlorination reaction with phosphorus oxychloride; the preparation method of 4-chloropyrrolopyrimidine provided by the synthesis route is a preparation method with high yield, low cost, easy operation and suitability for industrialization.

The invention provides a phenolic compound with a hangover alleviating effect and a preparation method thereof. The structural formula of the polyphenol compound 1-(2, 4-dihydroxyphenyl)-2-(4-O-glucosylphenyl) ethanone is as shown in formula (I), and the polyphenol compound 1-(2, 4-dihydroxyphenyl)-2-(4-O-glucosylphenyl) ethanone is separated from pueraria thomsonii. In-vitro pharmacological experiments prove that the compound 1-(2, 4-dihydroxyphenyl)-2-(4-O-glucosyl phenyl) ethanone has good acetylcholin esterase inhibitory activity, and the EC50 value of the compound 1-(2, 4-dihydroxyphenyl)-2-(4-O-glucosyl phenyl) ethanone is 0.41 + / -0.07 mM, which indicates that the compound 1-(2, 4-dihydroxyphenyl)-2-(4-O-glucosyl The polyphenol compound 1-(2, 4-dihydroxyphenyl)-2-(4-O-glucosylphenyl) ethanone is expected to be used as a lead compound to develop a novel alcohol effect dispelling and liver protecting medicine.

The invention provides a preparation process of (2E)-(3-hydroxy-4-methoxyl) cinnamyl aldehyde. The preparation process comprises the following steps: (1) adding 3-hydroxy-4-methoxyl benzaldehyde into an alkaline aqueous solution, and dissolving the 3-hydroxy-4-methoxyl benzaldehyde for later use; (2) introducing the solution obtained in the step (1) into a first inlet of a continuous flow reactor, wherein the flow velocity is 150.0-220mL / min; a vinyl acetate or acetaldehyde solution is introduced into a second inlet of the continuous flow reactor, the flow velocity is 10-30 mL / min, the retention time of the reaction solution in the continuous flow reactor is 5-10 min, and the reaction temperature is 50-100 DEG C; (3) adding reaction liquid of the continuous flow reactor into a reaction kettle for quenching under stirring; (4) after reaction quenching, filtering and collecting a precipitated solid crude product; (5) refluxing the obtained crude product in methanol, cooling, filtering and collecting the separated solid; and drying in vacuum until the weight is constant to obtain the (2E)-(3-hydroxy-4-methoxyl) cinnamyl aldehyde. According to the process, generation of dark impurities is avoided, the appearance quality and yield of the product are improved, continuous flow reaction is adopted, amplification is easy, and the amplification effect is avoided.

The invention discloses casei paracasei capable of degrading acetaldehyde and application of the casei paracasei in ethanol or acetaldehyde related diseases. The invention provides a new lactobacillus paracasei strain A22032 screened and separated from long-life human intestinal tracts, the new lactobacillus paracasei strain A22032 has an excellent acetaldehyde degradation effect, the in-vivo acetaldehyde degradation rate reaches 69.23% and is obviously superior to that of the existing same strain, and a new scheme is provided for preventing and relieving ethanol or acetaldehyde related liver injury.

The invention belongs to the technical field of lithium ion battery materials. The invention relates to a thermal insulation pad, in particular to a flame-retardant silicone rubber thermal insulation pad for a lithium battery module. In the heat insulation pad, the adopted flame retardant is prepared by the following specific steps: mixing aminopropyltrimethoxysilane, acetaldehyde and a first solvent, and heating for reaction to obtain an intermediate product; and dissolving the intermediate product and 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide in a second solvent, carrying out a heating reaction, then adding modified nano aluminum hydroxide, and continuing the heating reaction to obtain the nitrogen-phosphorus-silicon flame retardant with high flame retardance. The molar ratio of the aminopropyl trimethoxy silane to the acetaldehyde is (1.5 to 2.5): 1; the molar ratio of the intermediate product to the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is 1: (1.8-2.2), and the molar ratio of the intermediate product to the 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide is 1: (1.8

This invention discloses a craft beer flavor enhancement process using oak barrel micro-oxygen aging, belonging to the field of craft beer brewing technology. This process achieves the targeted transformation and accumulation of flavor compounds in craft beer through oak barrel pretreatment, precise control of the micro-oxygen environment, and optimization of aging process parameters. First, the oak barrel undergoes a combined pretreatment of toasting, carbonization, and maceration. Then, the fermented base beer is poured into the pretreated oak barrel, and a stable oxygen concentration is maintained within the barrel through a micro-oxygen control system, aging under suitable temperature conditions. Craft beer brewed using this process exhibits a significantly increased content of characteristic flavor compounds and an effective reduction in the content of off-flavor substances such as acetaldehyde. The beer combines the rich aroma of oak with the refreshing taste of beer, solving the problems of single flavor and prominent off-flavors in traditional aging processes, and significantly improving the quality and market competitiveness of craft beer.

This invention relates to the field of functional food technology, and more particularly to the application of safflower honey, or safflower honey extract, in enhancing the activity of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). The invention has found that safflower honey, or safflower honey extract, can effectively enhance ADH and ALDH activity, thereby promoting alcohol metabolism and achieving a hangover-relieving effect. Further research on the extract revealed that a mixture of syringaldehyde, riboflavin, lutein, luciferin, and three p-coumaroyl spermidine plays a key role in enhancing ADH and ALDH activity, thus providing an application of this mixture in hangover relief. The application of safflower honey and its extract provided by this invention has high application value for developing foods and health products with hangover-relieving effects.

The invention discloses a ferromagnetic element-doped lanthanum oxychloride two-dimensional material and a preparation method and application thereof, and belongs to the technical field of chemical catalysis, and the method comprises the following steps: dissolving lanthanum acetylacetonate and cobalt salt in oleylamine, uniformly mixing, adding a lanthanum chloride solution into a mixed system, and heating and stirring for reaction in an inert gas atmosphere to obtain a lanthanum oxychloride two-dimensional material; the heating temperature is 300-350 DEG C, the reaction time is 2-15 hours, and washing and drying the obtained product to obtain the ferromagnetic element doped lanthanum oxychloride two-dimensional material. The method is simple in step and mild in reaction condition, and the prepared ferromagnetic element doped lanthanum oxychloride two-dimensional material shows a two-dimensional ferromagnetic Moire superlattice structure at room temperature and can be used for producing high-added-value products such as acetaldehyde, propylene and butylene through photocatalytic conversion of CO2.

The present application provides a kind of kudzu vine cranberry composition for protecting liver from alcohol, which contains the following ingredients by weight: 30-50 parts of extract of Hovenia dulcis Thunb, 30-50 parts of mixed extract, 20-40 parts of extract of Pueraria lobata, 10-20 parts of extract of Poria cocos, 10-20 parts of extract of Glycyrrhiza uralensis, 0.05-0.1 parts of vitamin C; the raw materials of the mixed extract are mixed by cranberry and Fructus Lycii in a mass ratio of (1-2):(1-2). The present application further provides formulations and food containing the composition. The present application further protects the use of the composition or formulation in preparing health food or medicine with auxiliary protective effect on chemical liver injury. The composition provided by the present application can improve the activity of alcohol dehydrogenase / acetaldehyde dehydrogenase, reduce the content of MDA in tissues and increase the content of GSH, and reduce the content of triglyceride in liver cells, thereby comprehensively exerting the effect of protecting liver from alcohol, with high safety, small side effects, and wide sources of raw materials, and having important market value and development prospect.

The invention belongs to the technical field of medicine synthesis, and particularly relates to a preparation method of brexpiprazole. The preparation method comprises the following steps: by taking a compound 4-amino benzo [b] thiophene and chloroacetaldehyde as starting materials, carrying out substitution reaction to prepare an intermediate 2, 2 '-(benzo [b] thiophene-4-yl azane diyl) diacetaldehyde, and then carrying out reductive amination reaction on the intermediate 2, 2'-(benzo [b] thiophene-4-yl azane diyl) diacetaldehyde and 7-(4-amino butoxy) quinoline-2 (1H)-ketone to construct a piperazine ring, thereby preparing the target product bupremizole I, the product obtained by the process has high yield and purity, and is suitable for industrial production.

The invention discloses a preparation method of 4-chloromethylstyrene, and belongs to the technical field of synthesis of organic intermediates. 4-bromobenzaldehyde is adopted as a raw material and reacts with ethylene glycol under the action of p-toluenesulfonic acid to generate an intermediate 1; reacting with magnesium metal to generate a Grignard reagent, reacting with acetaldehyde, and hydrolyzing to generate an intermediate 2; finally, under the combined action of methyl dichlorosilane and tri (pentafluorophenyl) boron, the product 4-chloromethyl styrene is generated. The raw materials can be obtained in the market, the reaction of dehydrating benzyl alcohol into olefin and directly chlorinating aldehyde group to generate benzyl chloride is completed by a one-step method under the combined action of methyl dichlorosilane and tris (pentafluorophenyl) boron, the operation is simple and convenient, the overall yield is high, and a route reference is provided for synthesizing the compounds.

The application discloses a catalyst for preparing high-level unsaturated aldehyde through hydroxy aldehyde condensation reaction and a preparation method thereof. Specifically relates to a method for preparing propylene aldehyde through hydroxy aldehyde condensation reaction of a mixed solution of formaldehyde and acetaldehyde, in which, a basic metal is loaded on a modified CeO2 carrier; the reaction is carried out in a fixed bed under normal pressure; the catalyst provided by the application is cheap, and the preparation method is simple, efficient, and has the characteristics of high conversion rate of acetaldehyde in the reaction process, the highest conversion rate can reach 95%, and the selectivity of propylene aldehyde can reach 70%.

The utility model discloses an acetaldehyde oxime continuous membrane reaction production device, which comprises a sealing cover, a tank body arranged at the lower end of the sealing cover and a catalytic component arranged in the tank body, a flange pipe is arranged on the sealing cover, a feed port is arranged at the top end of the catalytic component, the feed port comprises a feed flange and a feed valve, and the feed flange is connected with the feed valve. The middle section of the catalysis assembly is a catalysis pipe, catalyst film material bins are evenly arranged on the catalysis pipe, a discharging port is formed in the bottom end of the catalysis assembly, a discharging valve is arranged at the bottom end of the discharging port, a clamping piece is arranged at the top end of the discharging port, the top end of the catalysis pipe is clamped in the flange pipe, and the bottom end of the catalysis pipe is clamped in the clamping piece. According to the acetaldehyde oxime continuous membrane reaction production device disclosed by the utility model, catalysts are filled in the catalyst membrane material bins in the plurality of groups of catalytic tubes which are connected in parallel, and the plurality of groups of catalyst membrane material bins which are connected in series increase the contact area between the catalysts and reactants, so that the utilization efficiency of the catalysts is increased.

The application discloses an aldolase bioelement screening method and related application of a series of aldolases in catalyzing a condensation reaction of formaldehyde and pyruvic acid to synthesize 4-hydroxy-2-ketobutyric acid. The aldolase provided by the application is a protein shown in SEQ ID NO. 1-NO. 10, or a functionally identical protein obtained through substitution and / or deletion / addition of one or more amino acid residues. The aldolase has the following characteristics: 1) belonging to the HpcH functional domain family protein; 2) the sequence length is 240-320 amino acids; 3) the existing database function annotation is 4-hydroxy-2-oxovalerate aldolase (can catalyze the condensation reaction of acetaldehyde and pyruvic acid); the aldolase can take formaldehyde and pyruvic acid as substrates, and can carry out enzyme catalysis reaction in appropriate conditions and medium, and can efficiently biosynthesize 4-hydroxy-2-ketobutyric acid, and has the remarkable characteristics of mild reaction condition, good stereoselectivity and no pollution.

The present application relates to the technical field of porphyrin-based covalent organic framework material preparation, in particular to a mild preparation method of acetaldehyde-based porphyrin covalent organic framework and application thereof, which comprises the following steps: step one: dispersing ligand 2', 5'-bis((ethyl sulfide) methyl)-[1,1':4',1''-triphenyl]-4,4''-diamine in acetonitrile solution to obtain solution A, and dissolving acetaldehyde-based porphyrin in dichloromethane to obtain solution B; step two: mixing solution A and solution B; step three: adding ferric chloride and acetic acid as catalysts to react under mild conditions to obtain acetaldehyde-based porphyrin covalent organic framework material, which has excellent gaseous iodine adsorption performance. The synthesis method provided by the present application has mild conditions, simplifies the high-temperature time-consuming shortcomings of traditional porphyrin-based covalent organic framework material synthesis, and realizes the synthesis of special ligand covalent organic framework.

The invention provides a novel production method of pentaerythritol, which relates to the technical field of chemical products, and comprises the following steps: proportioning formaldehyde, acetaldehyde and lithium hydroxide, mixing, carrying out condensation reaction, and adding formic acid to neutralize the solution after the reaction; collecting the neutralized solution, carrying out rectification treatment, and separating out crystals; carrying out centrifugal treatment on the separated crystals, and then putting the crystals into a washing tank for washing; drying to obtain a pentaerythritol finished product; precipitating the mother liquor, washing and refluxing the filtered solution, and mixing the filtered solution with the dealdehyding solution for cyclic utilization; and concentrating, crystallizing, centrifuging, washing and drying the filtrate to obtain a lithium formate product. According to the production method of the pentaerythritol by the lithium method, the reaction conversion rate is high, and the product quality is excellent; the added value is high, and the overall economy of the production process is good; the mother liquor is completely circulated in a closed manner, and is pollution-free and environment-friendly. The automation degree is high, and the washing, overturning and discharging processes can be completed only through single power equipment.

This invention discloses a method for synthesizing a tenapano hydrochloride intermediate. The synthesis method includes the following steps: (1) condensing the compound 3-bromophenylacetaldehyde and the compound N-methyl-(2,4-dichlorophenyl)methylamine under dehydration conditions to obtain an enamine intermediate; (2) subjecting the enamine intermediate to an intramolecular cyclization reaction in the presence of an acid catalyst to obtain the tenapano hydrochloride intermediate 4-(3-bromophenyl)-6,8-dichloro-2-methyl-1,2,3,4-tetrahydroisoquinoline. The synthetic route provided by this invention requires only two steps to construct the key framework, and has the advantages of short reaction steps, high overall yield, and no need to use highly toxic liquid bromine. This process has high atom economy, reduces the emission of waste gas, wastewater, and solid waste, and is suitable for large-scale industrial production under mild conditions.