1442results about "Carboxylic compound separation/purification" patented technology

The invention discloses a method for preparing high-purity nickel acetate from crude nickel carbonate in the technical field of nickel compound purification, which comprises the following steps: mixing the crude nickel carbonate with deionized water to obtain a suspension, and adding glacial acetic acid to react to obtain a nickel acetate solution; then a specially-made hierarchical-pore titanium silicalite molecular sieve loaded bimetallic nanocluster material is added for purification treatment, the material is obtained through precise preparation, the method comprises the steps of carrier modification, bimetallic loading, hydrophobic modification, activation balance and the like, and the material has excellent impurity adsorption capacity and chemical stability; carrying out concentration crystallization and solid-liquid separation on the purified solution to obtain wet nickel acetate crystals; the mother liquor is subjected to adsorption treatment again, crystals in the mother liquor are recycled, and finally all the crystals are combined and dried to obtain a high-purity nickel acetate product. The process is simple and efficient, the purity of the prepared nickel acetate exceeds 98.5%, the content of each impurity is superior to the industrial standard, and the mother liquor can be recycled, is environment-friendly and is suitable for industrial production.

The invention provides a method for separating EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) through supercritical fluid chromatography, and relates to the technical field of separation and purification. The invention provides a method for separating EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) by supercritical fluid chromatography, which comprises the following steps: by taking supercritical carbon dioxide and an organic reagent as mobile phases, and by utilizing the specific mobile phase property of supercritical CO2 after being mixed with the organic reagent (saturated aliphatic hydrocarbon) and matching with a normal-phase chromatographic column, separating the EPA from the DHA by supercritical fluid chromatography. A specific stationary phase (one or more of a silica gel surface bonded propylurea stationary phase, a silica gel surface bonded phenyl stationary phase and a silica gel surface bonded imidazolyl stationary phase) is adopted, effective separation and preparation of the EPA and the DHA in the fish oil can be achieved, the EPA and the DHA in the fish oil can be effectively separated within 50 min, the separation speed is high, the separation effect is good, and the method is suitable for industrial production. The purity of the obtained EPA and DHA is 98% or above, the purity of the EPA and the DHA is high, and the EPA and the DHA have good application prospects in the fields of medicine production and food and health care products.

The invention discloses a hydrofining method for optimizing the chromatic value of a bio-based terephthalic acid product, and belongs to the technical field of terephthalic acid hydrofining. The special refining process suitable for the bio-based CTA is formed by optimizing the whole process of pretreatment, hydrogenation reaction and post-treatment. The process not only solves the problem that the bio-based raw material has many impurities, but also realizes the balance of environmental protection and economy through the green solvent (water), the efficient catalyst (Pd / C) and controllable parameter design, provides a feasible path for the industrial production of bio-based PTA, and promotes the transformation of the polyester industry to sustainable development. The method provided by the invention is high in impurity removal rate, can efficiently purify the bio-based CTA to obtain a product meeting the PTA standard, is mild in reaction condition, realizes low-energy-consumption and high-stability operation under efficient catalysis, is small in process pollution, and reduces the environmental load.

The invention provides a betaine succinate eutectic crystal as well as a preparation method and application thereof, and belongs to the technical field of eutectic crystal manufacturing. The structural formula of the succinic acid betaine eutectic crystal is shown as a formula I, the molecular formula of the succinic acid betaine eutectic crystal is C28H56N4O16, in the succinic acid betaine eutectic crystal, the molar ratio of succinic acid to betaine is 1: 2, and the succinic acid betaine eutectic crystal has low irritation and excellent effects.

The invention discloses a preparation method of a nylon 66 salt crystal, which is characterized in that in the method, a nylon 66 salt aqueous solution is subjected to secondary crystallization and a rotary pressure filter process to prepare the nylon 66 salt crystal. According to the technology, the problems of low single-stage yield and large sewage discharge amount are solved by adopting secondary crystallization and evaporation condensate recycling, and the processes of centrifugation, drying, cyclone separation and the like are reduced by replacing a centrifugal machine with a rotary pressure filter, so that the energy consumption per ton of products is reduced.

The invention belongs to the technical field of impurity separation, and particularly discloses a method for separating and purifying impurities in a process for preparing glyoxylic acid through oxalic acid electrolysis, a crystallization kettle is included, an isolation device is arranged in the crystallization kettle, and the isolation device comprises a conical top cover, a conveying pipe, an annular filter screen, a directional conveying assembly and a sealing assembly; the conical top cover is arranged at the axis of the crystallization kettle, an opening of the conical top cover faces downwards, and a plurality of fixing rods are fixedly connected between the top of the conical top cover and the inner wall of the side face of the crystallization kettle. According to the method, glyoxylic acid product solutions with different concentration specifications and the high-purity glyoxylic acid crystal can be obtained after the electrolyte is sequentially subjected to pre-evaporation, electrodialysis, secondary evaporation, cooling crystallization, solid-liquid separation, washing and drying and other procedures, so that the prepared high-purity glyoxylic acid crystal can be popularized and applied in the field of high-end medicine.

The invention discloses equipment and a method for preparing an electronic-grade salicylic acid solution. The equipment comprises an acidification tank, an alkali tank, a micron filter, an anion filter, a cation adsorption column and a nano filter. The acidification tank is used for loading a salicylic acid solution and an acidic substance, and the alkali tank is used for loading an eluent. The method comprises the following steps: firstly, removing large impurities from a salicylic acid solution and acidic substances through a micron filter, then conveying the salicylic acid solution and acidic substances to an anion filter, adsorbing salicylic acid through anion adsorption resin to obtain phenol, removing the phenol, then introducing an eluent, washing off the salicylic acid solution, conveying the salicylic acid solution to a cation adsorption column to remove metal ions, and finally conveying the salicylic acid solution and the acidic substances to a nano filter to obtain the purified salicylic acid. And reducing the granularity of the salicylic acid solution to obtain the electronic-grade salicylic acid solution. The electronic-grade salicylic acid solution has the advantage of strong selective complexing ability to metals, and has a good wet etching effect in the integrated circuit manufacturing process.

The invention belongs to the technical field of separation of drug intermediates, and particularly relates to a control method for a process impurity 2-ethyl valeric acid (EP-B) in preparation of valproic acid or sodium valproate by a diethyl malonate method. According to the method disclosed by the invention, the content of 2-ethyl-2-propylmalonic acid process impurities in dipropylmalonic acid is controlled, so that the content of 2-ethylvaleric acid (EP-B) which is a process impurity in valproic acid or sodium valproate is accurately controlled; adding a polar solvent into the dipropylmalonic acid crude product, heating, pulping for a certain time, cooling, filtering and drying to obtain a high-purity dipropylmalonic acid refined product; high-purity valproic acid (RRT is equal to 1.00) is prepared through decarboxylation of the dipropyl malonic acid fine product, and the purity is 99.779%; 0.020% of 2-ethyl valeric acid (RRT is equal to 0.90); and valeric acid (RRT = 0.77), 0.039%. The valproic acid product quality meets the requirements of European Pharmacopoeia. According to the method, the problems of quality control and process evaluation of valproic acid or sodium valproate prepared by a diethyl malonate method are solved.

The invention discloses a method and a system for producing high-purity medium-chain fatty acid (MCFA) based on waste molasses two-stage regulation fermentation. Comprising the following steps: (1) diluting waste molasses, then adding a compound enzyme agent of pectinase, beta-glucanase and cellulase, and coupling microwave to assist treatment; (2) inoculating the pretreated waste molasses with a composite flora containing a clostridium kluyveri mutant strain and a Megasphaera elsdeni engineering bacterium, and carrying out a fermentation treatment on the waste molasses, wherein the composite flora contains the clostridium kluyveri mutant strain and the Megasphaera elsdeni engineering bacterium; (3) sequentially performing two-stage dynamic regulation and control fermentation on the waste molasses inoculated with the composite flora through a pH-stat control strategy to realize efficient conversion from butyric acid to hexanoic acid / octanoic acid; and (4) a hydrophobic hollow fiber membrane module is adopted to realize on-line removal of the product, and the inhibition effect of the product is relieved. According to the technology, the yield of the MCFA produced from the waste molasses reaches 0.45 g / g COD, the cost is reduced by 68% compared with that of a traditional substrate, and a new way is provided for recycling of sugar manufacturing waste.

The invention relates to the technical field of organic synthesis, in particular to a preparation method of butynedioic acid. The preparation method of the butynedioic acid comprises the following steps that butynediol is oxidized into the butynedioic acid through pypocholoride and a catalyst, and the catalyst comprises carbon black and a metal compound loaded on the carbon black. According to the invention, butynediol is used as a raw material, and butynediol is oxidized by using pypocholoride and a catalyst to prepare butynedioic acid. Wherein butynediol is easy to obtain, and the raw material cost is low. In addition, the catalyst uses carbon black to immobilize a metal compound, conversion of pypocholoride into a large number of reactive oxygen free radicals can be accelerated, butynediol can be efficiently oxidized under the action of pypocholoride and the catalyst, and the whole synthesis route is safe and green, simple and feasible in process, low in equipment requirement, low in operation cost, free of secondary pollution and low in production cost.

The invention belongs to the technical field of separation of drug intermediates, and particularly relates to a method for preparing a high-purity dipropylmalonic acid refined product by adding a polar solvent into a dipropylmalonic acid crude product, heating, pulping for a certain time, cooling, filtering and drying. Decarboxylating the refined dipropylmalonic acid product to obtain high-purity valproic acid; distilling the filtrate to recover the polar solvent to obtain 2-methyl-2-propylmalonic acid, and carrying out decarboxylation on the 2-methyl-2-propylmalonic acid to obtain 2-methylpentanoic acid; 2-methylvaleric acid is used as a perfume additive. According to the method disclosed by the invention, the process impurity 2-methyl-2-propylmalonic acid in dipropylmalonic acid is separated, and the process impurity 2-methylvaleric acid (EP-L) in valproic acid or sodium valproate is precisely separated; the quality of the valproic acid product prepared by the method disclosed by the invention meets the requirements of European Pharmacopoeia EP-11 (2023). According to the invention, the problems of quality control and process evaluation of valproic acid or sodium valproate prepared by a dimethyl malonate method are solved.

The invention discloses a potassium propionate continuous synthesis process, and relates to the technical field of potassium propionate synthesis, the process comprises the following steps: S1, raw material pretreatment: selecting fermentation waste liquid containing propionic acid and acetic acid and potassium ore leaching liquid containing potassium hydroxide and potassium carbonate as composite raw materials, adding a composite chelating agent into the potassium ore leaching liquid, and uniformly stirring; according to the method, the composite raw material system composed of the fermentation waste liquid and the potassium ore leaching liquid is adopted, and the composite chelating agent is added, so that resource utilization of industrial waste is achieved, the raw material cost is reduced, meanwhile, impurities are prevented from interfering with continuous reaction, and through gradient temperature control-pressure cooperative regulation and linkage regulation of the PLC system, the yield is increased. The problem of product deliquescence caused by local overheating is solved, volatilization loss of propionic acid is reduced, the adaptability of the technology to raw material batch fluctuation is improved through raw material concentration online detection and dynamic parameter adaptation, the continuous production stability is guaranteed, and finally synchronous improvement of the potassium propionate synthesis efficiency and the product quality is achieved.

The invention provides a method for separating and extracting bio-based succinic acid from fermentation liquor, which comprises the following steps: (1) enabling the fermentation liquor to sequentially pass through a ceramic membrane and a nanofiltration membrane, and decoloring to obtain bio-based succinic acid decolored liquor; (2) sequentially carrying out ion exchange impurity removal and concentration treatment on the bio-based succinic acid decoloring solution to obtain a bio-based succinic acid concentrated solution; and (3) carrying out multi-stage cooling crystallization on the bio-based succinic acid concentrated solution to obtain the bio-based succinic acid, the multi-stage cooling crystallization comprises first-stage crystallization, second-stage crystallization and third-stage crystallization which are carried out in sequence. Through the steps of integrated membrane filtration, decoloration, ion exchange, concentration, multi-stage crystallization and the like, thalli, proteins, pigments, inorganic ions and other impurities in fermentation liquor can be efficiently removed, so that a high-purity bio-based succinic acid product is obtained, meanwhile, the product yield is increased, and energy consumption and waste discharge are reduced.

The present invention provides a method for purifying a polyester depolymerization product in which impurities and poorly soluble dyes and pigments are removed from a material produced by polyester depolymerization so as to minimize impurity content and perform decolorization.

The invention relates to the technical field of sodium ion batteries, and discloses a preparation method of a sodium battery additive and application of the sodium battery additive in a sodium battery, and the preparation method comprises the following steps: a) a reaction step: in an isopropanol solvent, enabling pyromellitic acid and sodium hydroxide to react under heating and stirring; after the reaction is finished, filtering a reaction product to obtain a benzene tetracarboxylic acid sodium crude product; b) a purification step: dissolving the benzene tetracarboxylic acid sodium crude product in water, and heating for rotary evaporation until the solution reaches a saturated state; adding methanol into the solution in the saturated state to separate out a solid, and filtering a mixture containing the solid while the mixture is hot; and carrying out vacuum drying on the solid obtained by filtering to obtain the sodium electric additive. According to the invention, the high-purity product is used as the sodium-ion battery additive, and the comprehensive performances of high-temperature circulation, high magnification, low temperature and the like of the battery can be comprehensively and obviously improved through a unique mechanism of synchronously forming a stable protective film on a positive electrode and a negative electrode.

Inhibitor compositions for abating undesirable emulsion polymerization during processing of hydrocarbon stream laden with reactive vinylic monomers are provided. The polymerization inhibitor compositions include at least a first inhibitor compound having a stable nitroxide radical and a second inhibitor including phenylenediamine. Methods of inhibiting the polymerization of monomers using the compositions of the disclosure are also provided. The methods of inhibiting polymerization of monomers include a step of adding a composition of the disclosure to a process stream. The process stream includes an ethylenically unsaturated monomer that is suspended in the bulk-phase and highly polar solvents as distractive distillation solvents.

The invention discloses a preparation method of ethyl 4-chloroacetoacetate, and belongs to the technical field of compound synthesis. The method comprises the following steps: by taking diketene as a raw material, adding a polymethylsilsesquioxane polymerization inhibitor into a dichloromethane solvent, introducing chlorine at low temperature, carrying out chlorination reaction to generate 4-chloroacetoacetic acid, then esterifying the 4-chloroacetoacetic acid with absolute ethyl alcohol to obtain a crude product, and finally distilling and purifying to obtain the product. The preparation method is characterized in that a polymethylsilsesquioxane polymerization inhibitor is added before chlorination reaction, the polymerization inhibitor is prepared by grafting a functional monomer containing a 3, 5-di-tert-butyl-4-hydroxycinnamic acid structure onto surface-ethenylated polymethylsilsesquioxane microspheres, and the polymethylsilsesquioxane polymerization inhibitor has both steric hindrance and free radical capture capability. The method can effectively inhibit the self-polymerization and copolymerization tendency of diketene, intermediates and products in a reaction system, obviously reduces the generation of by-products such as dichloro and polychloro, enables the product to be high in yield and good in purity, and meets the quality requirements of high-end medical intermediates.

The invention provides a botanical fungicide of a chaulmoogra seed extract, which takes sub-chaulmoogra seed oleic acid as a marker, and application of the botanical fungicide in preparation of medicines for preventing and treating plant diseases caused by pathogenic fungi and oomycetes. The hydnocarpus anthelmintica extract is obtained by extracting hydnocarpus anthelmintica seeds with a plurality of different types of organic solvents such as ethanol, petroleum ether and the like and treating the seeds by a physical method, and the hydnocarpus anthelmintica extract contains sub-hydnocarpus anthelmintica oleic acid as markers in different proportions. The extract has the effects of inhibiting conidium germination, bud tube growth or appressorium formation of fungi and oomycetes, effectively preventing pathogenic bacteria from infecting host plants and preventing and treating important plant diseases such as rice blast, mango anthracnose, potato late blight and rice false smut.

The invention provides a bio-based crude terephthalic acid hydrofining method, and belongs to the technical field of terephthalic acid hydrofining. The method comprises the following steps: carrying out recrystallization pretreatment on bio-based crude terephthalic acid, mixing the pretreated bio-based crude terephthalic acid with a solvent, adding a catalyst, carrying out a hydrofining reaction, replacing the solvent after the reaction is finished, carrying out recrystallization treatment on a hydrofined product, washing with water, and drying to obtain refined terephthalic acid, the method disclosed by the invention has the advantages of high impurity removal rate, mild reaction conditions and small process pollution, the refining of the bio-based crude terephthalic acid is realized, the obtained terephthalic acid can meet the requirements of an existing industrial method, and the concentration of impurities p-carboxybenzaldehyde is less than or equal to 25ppm and the concentration of methyl benzoic acid is less than or equal to 180ppm.

The invention belongs to the technical field of automatic control, and discloses a cyclopropylamine (R)-mandelate crystallization process feedback control method, which comprises the following steps: acquiring the concentration, solvent temperature, stirring speed and pH value of cyclopropylamine (R)-mandelate in a solvent in real time, and forming a state parameter set reflecting the real-time state of a cyclopropylamine (R)-mandelate crystallization system; based on the state parameter set, deriving a solute supersaturation degree change rate, a nucleation rate and a crystal growth rate by adopting an explicit kinetic relationship to obtain a kinetic feature set of the cyclopropylamine (R)-mandelate; collecting the grain size, the shape and the crystallization uniformity of the crystal, and constructing a corresponding crystal quality prediction function in combination with the kinetic feature set of the cyclopropylamine (R)-mandelate to obtain a predicted crystal quality index; comparing the actually detected crystal morphology index with the predicted crystal quality index, and calculating to obtain a deviation value; the crystal quality of the cyclopropylamine (R)-mandelate is improved.

The invention discloses a preparation process of a Baloxavir marboxil and tropine acid eutectic crystal form. The X-ray powder diffraction pattern of the Baloxavir marboxil and tropine acid eutectic crystal form under Cu-Ka radiation has diffraction angle 2theta values of 4.7 + / -0.2 degrees, 9.1 + / -0.2 degrees, 10.0 + / -0.2 degrees, 10.8 + / -0.2 degrees, 11.9 + / -0.2 degrees, 13.4 + / -0.2 degrees, 14.1 + / -0.2 degrees, 15.0 + / -0.2 degrees, 16.4 + / -0.2 degrees, 17.5 + / -0.2 degrees, 18.0 + / -0.2 degrees, 19.1 + / -0.2 degrees, 20.5 + / -0.2 degrees, 21.5 + / -0.2 degrees, 22.5 + / -0.2 degrees, 23.8 + / -0.2 degrees, 24.5 + / the angle is 30.7 + / -0.2 degrees, and the angle is 31.6 + / -0.2 degrees. And characteristic peaks exist at all positions. The Baloxavir marboxil and tropine acid eutectic crystal form provided by the invention has stable physicochemical properties, excellent solid stability and mechanical stability, and can be stably stored for a long time, the preparation method is simple and convenient, the repeatability is good, and the Baloxavir marboxil and tropine acid eutectic crystal form has important application value for the development of the medicine in the future.

The invention provides a preparation method and application of high alpha-linolenic acid, and relates to the technical field of medicines. Comprising the following steps: selecting purple perilla seeds, cleaning, drying, mechanically grinding in a protective atmosphere, and filtering to obtain purple perilla seed crude oil; carrying out degumming, deacidification, decoloration and dewaxing treatment on the crude perilla seed oil in a protective atmosphere to obtain primarily enriched crude alpha-linolenic acid oil; and respectively carrying out supercritical CO2 extraction, enzymatic molecular distillation and preparative chromatographic separation on the preliminarily enriched perilla seed oil to obtain the high alpha-linolenic acid. According to the method, purple perilla seeds are subjected to multi-stage treatment, extraction and refinement are performed layer by layer through three steps of supercritical CO2 extraction, enzymatic molecular distillation and preparative chromatographic separation, free fatty acid in purple perilla seed crude oil can be effectively removed, and alpha-linolenic acid is enriched to obtain high alpha-linolenic acid with the purity higher than 96%. The method is suitable for mass production in the medicine field.

The invention relates to the technical field of separation and purification, in particular to a method for recovering cis-15-tetracosenoic acid from an acer truncatum seed oil byproduct, which comprises the following steps: selecting the acer truncatum seed oil byproduct, crushing, sieving, washing, adding modified attapulgite and beta-cyclodextrin, stirring and adsorbing at constant temperature, and filtering; preparing the modified attapulgite; adding a KOH-EtOH solution containing lipase and polyethylene glycol into a pretreated product for refluxing, and adding a saturated saline solution for refluxing; standing and layering the reaction liquid, and extracting, acidifying, washing, drying and distilling an organic phase to obtain mixed fatty acid; and carrying out composite purification to obtain a pure cis-15-tetracosenoic acid product. According to the method, the purity and the extraction rate of the cis-15-tetracosenoic acid are remarkably improved, the oxidation, heat and storage stability of the product is enhanced, the color is improved, and the comprehensive application performance is better.

The invention provides bio-based succinic acid and a preparation method and application thereof, the median particle size of the bio-based succinic acid is 300-500 [mu] m, and the bio-based succinic acid comprises the following particles in percentage by mass: 0-10% of particles with the particle size of d1, 30-40% of particles with the particle size of d2, 40-50% of particles with the particle size of d3 and 8-18% of particles with the particle size of d4, d1 is less than 150 [mu] m, 150 [mu] m < = d2 < 300 [mu] m, 300 [mu] m < = d3 < 500 [mu] m, and d4 > = 500 [mu] m. The bio-based succinic acid is large in particle size, controllable in particle size distribution and good in uniformity, not only solves the problem of dust raising in succinic acid application, but also can reduce the adhesive force among particles and avoid the problems of agglomeration and caking, so that the storage time of the bio-based succinic acid is prolonged, the succinic acid has proper friction force, and the service life of the bio-based succinic acid is prolonged. The storage performance and the downstream application performance are improved, and the application requirements of various scenes are met.

The invention belongs to the technical field of chemical production, and particularly relates to a novel process for separating pentaerythritol by a membrane method and application of the novel process. The membrane separation comprises the steps of separating sodium formate by using an ion exchange membrane and separating pentaerythritol by using a low-pressure nanofiltration membrane device. The dealdehyding liquid is separated through different membranes, and formic acid, pentaerythritol, dipentaerythritol and other substances can be effectively separated. The process greatly shortens the process flow and saves the cost. According to the technical scheme, the quality and performance of the pentaerythritol product are remarkably improved, the added value of the product is increased, and a new technical scheme is provided for industrial production of pentaerythritol.

The invention discloses a preparation process of a Baloxavir marboxil and L-tartaric acid eutectic crystal form. The X-ray powder diffraction pattern of the Baloxavir marboxil and L-tartaric acid eutectic crystal form under Cu-Ka radiation has diffraction angle 2theta values of 8.7 + / -0.2 degrees, 10.8 + / -0.2 degrees, 11.6 + / -0.2 degrees, 13.2 + / -0.2 degrees, 13.8 + / -0.2 degrees, 14.3 + / -0.2 degrees, 15.8 + / -0.2 degrees, 16.2 + / -0.2 degrees, 16.4 + / -0.2 degrees, 17.5 + / -0.2 degrees, 18.6 + / -0.2 degrees, 18.9 + / -0.2 degrees, 19.4 + / -0.2 degrees, 19.8 + / -0.2 degrees, 20.1 + / -0.2 degrees, 20.7 + / and characteristic peaks exist at the positions of 25.7 + / -0.2 degrees, 26.4 + / -0.2 degrees, 26.8 + / -0.2 degrees, 27.6 + / -0.2 degrees, 28.3 + / -0.2 degrees, 28.6 + / -0.2 degrees, 29.1 + / -0.2 degrees, 29.7 + / -0.2 degrees, 31.4 + / -0.2 degrees, 32.0 + / -0.2 degrees, 35.4 + / -0.2 degrees, 35.8 + / -0.2 degrees, 36.1 + / -0.2 degrees, 36.7 + / -0.2 degrees and 37.4 + / -0.2 degrees. The Baloxavir marboxil and L-tartaric acid eutectic crystal form provided by the invention has stable physicochemical properties, excellent solid stability and mechanical stability, and can be stably stored for a long time, the preparation method is simple and convenient, the repeatability is good, and the Baloxavir marboxil and L-tartaric acid eutectic crystal form has important application value for the development of the medicine in the future.

The application provides a method for continuous synthesis of medium-chain fatty acids, and belongs to the technical field of biochemistry and resource recycling. The application provides a method for continuous synthesis of medium-chain fatty acids, which comprises the following steps: mixing pretreated vinasse and a polyvinyl alcohol-sodium alginate composite matrix to obtain a fermentation matrix; adding the fermentation matrix to a fermentation system to perform pre-acidification; after the pre-acidification is completed, adjusting the feeding and discharging of the fermentation system every day, adjusting the material residence time to 9-15 days through the discharging amount, controlling the pH of the top region of the fermentation system to be 4.0-5.5 and / or the ORP to be-350--150 mV, and constructing an axial coupling system of the lactic acid production area of the top hydrolysis acidification area and the medium-chain fatty acid synthesis area of the bottom region of the fermentation system. The method does not need to add exogenous inoculum, and can realize the continuous synthesis of medium-chain fatty acids through partition regulation.

The invention belongs to the technical field of medical analysis, and particularly relates to a method for separating chemical components in hemsley rockvine root. According to the present invention, various chromatography methods are adopted to carry out separation and purification, such that sitroside (I), vanillyl glycolII (II), 5-hydroxymaltol (III), vanillic acid (IV), afzelin (V), 2, 3-dihydroxypyrazole (9E, 11E)-13-hydroxypyrazole (9, 11-dienoate), and 2, 3-dihydroxypyrazole (10E, 12E)-9-hydroxypyrazole (10, 12-dienoate) are obtained from hemsley rockvine root. Wherein the compounds II, III, VI and VII are separated from the hemsley rockvine root for the first time, and development and quality control of the hemsley rockvine root medicinal material are facilitated.

The invention discloses a green synthesis process of non-steroidal loxoprofen sodium, and relates to the field of loxoprofen sodium synthesis. A water / organic two-phase free radical bromination and functionalized Pd-Ru / NH2-ZIF-8 catalysis one-step hydrogenation degreasing-tert-butyl ester removal path is adopted. The catalyst is modified by a thiol ligand and cooperates with a chiral inducer to construct a Pd-Ru bimetallic active site, so that the product purity and the product yield are effectively improved, and the catalyst can be repeatedly used. The method is environment-friendly and efficient in process and suitable for industrial application.

The invention provides an energy-saving method and device for producing feed-grade propionic acid by using methanol carbonylation acetic acid waste liquid. The methanol carbonylation acetic acid waste liquid comprises the following components in percentage by mass: 40-80% of acetic acid, 20-60% of propionic acid and the balance of high-boiling residues, the method comprises the following steps: (1) evaporating the waste liquid by adopting a film evaporator with a scraper conical structure at the bottom to obtain a first gas phase and first kettle residues, controlling the evaporation rate to be 50-85% in the evaporation process, and keeping the first kettle residues in a flowing state; 2) directly feeding the first gas phase obtained in the step 1) into a recovery rectifying tower to obtain a second gas phase and crude propionic acid, and condensing the second gas phase to obtain acetic acid; 3, the crude propionic acid obtained in the step 2 passes through a resin tower, trace impurity metal ions are removed, and then the feed-grade propionic acid product is obtained.The method is simple in technological process, low in energy consumption and capable of running continuously, the content of the recycled propionic acid is larger than or equal to 99.5%, and the concentration of the impurity metal ions reaches the feed-grade standard.