2131 results about "Side product" patented technology

The invention discloses a supported nickel catalyst for preparing 1, 3-propylene glycol through hydrogenation of 3-hydroxypropionaldehyde as well as a preparation method and application of the supported nickel catalyst, and relates to the technical field of catalysts. The modified long-chain multi-carbon inducer is used, and a special long-chain molecular structure and a branched chain group of the inducer can effectively and selectively adsorb and occupy a micropore impregnation site; the preparation method has the beneficial effects that more active component nickel species are obviously promoted to be dispersed in main reaction confinement spaces such as mesopores and macropores and interact with the carrier to form effective active sites, and active component steeping liquor is inhibited from entering micropore channels due to capillary action; the active site failure caused by agglomeration of nickel species in micropores in the subsequent drying and roasting process of the catalyst precursor is avoided, the efficient and directional reaction is ensured, the generation of by-products is greatly reduced, the pressure is relieved for the subsequent product rectification separation, and the final product purity is improved. The catalyst provided by the invention can still keep an excellent catalytic effect when the air speed of a 3-hydroxypropionaldehyde solution is increased to 6.5 h <-1 >.

The invention discloses a multifunctional cellulolytic enzyme and application thereof in degradation of agricultural by-products, and belongs to the technical field of biology. The multifunctional cellulolytic enzyme is named RuCelI, and the amino acid sequence of the multifunctional cellulolytic enzyme is as shown in SEQ ID NO. 1. Based on a rumen microbial metagenome resource mining technology, a novel multifunctional cellulose decomposition enzyme RuCelI is developed, and the enzyme has double activities of endo-cellulase and xylanase, can be used for degrading agricultural by-products, reducing the treatment cost and improving the degradation efficiency, and is beneficial to improving the utilization rate and the economic benefit of the agricultural by-products.

The invention provides a catalyst, a preparation method and application thereof, and a method for preparing primary amine by catalyzing nitrile compound hydrogenation, and particularly relates to the technical field of catalyst synthesis. The catalyst comprises a nickel / cobalt-based catalyst and a metal salt; wherein the nickel / cobalt-based catalyst is selected from any one of a supported nickel / cobalt-based catalyst, a Raney nickel / cobalt catalyst or a nickel / cobalt nanocrystal; the metal salt comprises any one or a combination of at least two of tungsten salt, molybdenum salt, vanadium salt, aluminum salt and cerium salt. The metal salt and the nickel / cobalt main catalyst have a synergistic effect: the surface electron density is adjusted through electron transfer, the hydrogen dissociation and cyano adsorption activation capacities are enhanced, the hydrogenation activity is improved, and the mild condition reaction is assisted; the surface chemical environment is changed or steric hindrance is borrowed, the primary amine selectivity is improved, and byproducts are inhibited; aluminum salt, cerium salt and the like inhibit nickel / cobalt agglomeration, increase active sites, enhance stability, prolong the service life and reduce the dosage.

The invention relates to the field of caprolactam production, and discloses a green and efficient production process and device. The process comprises the following steps: continuously oximating cyclohexanone and hydroxylamine in a microreactor under the catalysis of mesoporous silica solid acid; carrying out gas phase rearrangement on cyclohexanone-oxime in the presence of a ZSM-5 molecular sieve under the assistance of microwaves; coupling, rectifying and purifying the crude product through a four-stage molecular sieve membrane; and performing catalytic cracking on the by-product to obtain N2 / H2O and recycling. The device comprises a micro-reaction unit, a microwave-radial reactor, a membrane coupling rectifying tower group and a tail gas cracking unit. Zero emission of ammonium sulfate is achieved, the product purity is larger than or equal to 99.95%, and energy consumption is reduced by 45%.

The invention belongs to the technical field of solid waste utilization, and particularly relates to a modified ZSM-5 molecular sieve catalyst and a preparation method and application thereof. The catalyst comprises a ZSM-5 molecular sieve and an active component, wherein the active component is loaded on the internal pore channel and the surface of the ZSM-5 molecular sieve; the active component comprises one or more of Zn, Fe, Ni, Co, Mo and Zr. By adjusting the loading capacity of the active components and the acidity of the catalyst and adjusting the interaction among the components of the catalyst, the high-density polyethylene plastic is used as a raw material, and the catalyst is simple in structure, single in element, free of oxygen element and low in by-product content; the modified ZSM-5 molecular sieve catalyst is simple in preparation process and low in production cost, and the catalyst takes high-density polyethylene plastic as a raw material, so that the yield of MAHs prepared by directional pyrolysis of the high-density polyethylene plastic as the raw material and the stability of the catalyst are effectively improved.

The invention discloses an ether polymerization inhibitor special for a butadiene extraction system and a preparation method of the ether polymerization inhibitor. The ether polymerization inhibitor comprises the following raw materials: a polymerization inhibitor intermediate, a solvent and a dispersing agent, the production process comprises the following steps: preparing a polymerization inhibitor intermediate, preparing a solvent, compounding, feeding and mixing, filtering, removing impurities and detecting. According to the method, firstly, a polymerization inhibitor 701 and diethylene glycol normal pressure etherification process is adopted, and beta-hydroxyethyl methyl ether is introduced to seal a terminal group, so that the power consumption is reduced, the generation of byproducts is inhibited, the solubility of an intermediate acetonitrile is improved to be greater than or equal to 30g / L, and the anti-interference performance is greatly enhanced; the solvent doped with a small amount of silane modified nano diatomite is prepared, impurities can be adsorbed, metal ions can be chelated, the dispersing agent can be assisted to be evenly distributed, the problems that a pure water solvent is single in function and the dispersing agent is prone to agglomeration are solved, and the polymerization inhibition efficiency and the stability of an extraction system are guaranteed.

The invention relates to the field of phosphorus-nitrogen flame retardants, and discloses a preparation method and application of a novel phosphorus-containing nitrogen oxide flame retardant, the preparation method comprises the following steps: S1, under the protection of nitrogen, dissolving diphenylphosphinyl hydroxylamine and triethylamine in a tetrahydrofuran solvent to prepare a reaction substrate solution; s2, slowly dropwise adding a diphenylphosphinyl chloride solution into the solution, and then sufficiently carrying out the reaction in a staged heating and heating reflux mode; s3, cooling and filtering to remove solid byproducts generated by reaction, and concentrating filtrate to obtain a crude product solid; and S4, recrystallizing and purifying the crude product by using ethyl acetate, and finally heating and drying the obtained crystal under a vacuum condition to obtain the product. An N-O group is innovatively introduced into the molecular structure of the flame retardant, so that the effect of efficiently capturing gas-phase free radicals in cooperation with a phosphorus-containing group is achieved, and the substantive technical progress that the material can be endowed with excellent flame retardant property with extremely low addition amount is realized.

The invention belongs to the field of chemical engineering manufacturing industry, and relates to equipment and a method for producing cyclic ketone compounds by oxidizing cycloolefin by using waste gas produced by adipic acid. Raw material gas A containing nitrous oxide from an adipic acid production process production line can be subjected to oxygen removal, so that the oxygen content is less than 100ppm; the raw material gas A containing nitrous oxide from the adipic acid production line can also be purified into purer gas containing 50-99% of N2O, and the purer gas is used for reacting with the cycloolefin compound; the reaction equation is CnH2n-2 (cycloolefin) + N2O (nitrous oxide)-> CnH2n-2O (a product cyclic ketone compound) + a byproduct + N2 superscript (nitrogen), wherein n is a positive integer from 4 to 24. The device is stable in consumption quota, low in production cost and high in economic benefit compared with the prior art.

The invention provides chlorotrifluoroethylene continuously prepared based on a microchannel reactor and a preparation method of the chlorotrifluoroethylene, and the chlorotrifluoroethylene comprises the following raw materials in parts by weight: 1, 1, 2-trifluoro-1, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 The low-temperature refrigerant refrigerant is prepared from the following components in parts by weight: 90 to 100 parts of 1, 2-trichloroethane, 1 to 5 parts of a zinc fluoride induced palladium-copper bimetallic catalyst, 8 to 15 parts of a cyclohexyl dimethyl ether-formic acid composite hydrogen donor, 0.5 to 2 parts of trifluoroacetic anhydride, 0.1 to 0.5 part of a perfluoropolyether lubricant, a proper amount of a low-temperature mixed refrigerant and 15 to 20 percent by weight of diluted hydrochloric acid. According to the invention, the preparation efficiency and product purity of chlorotrifluoroethylene can be improved, and stable operation of the preparation system and reasonable treatment of byproducts can be guaranteed.

The invention relates to the technical field of purification of fine chemical intermediates, in particular to a purification method of a mannitol carbonate sulfate preparation process intermediate, which comprises the following steps: S1, synthesizing diacetone-D-mannitol; s2, preparing an organic solution containing solids; s3, performing deprotection reaction to prepare a solid crude product; s4, removing unreacted solids; s5, extracting and separating by-product solids; and S6, purifying the target product solid and recovering mannitol. Through system separation and multi-component recovery, preparation of a high-purity product and cyclic utilization of unreacted substances, byproducts and raw materials are realized, the yield is remarkably improved, the cost is reduced, and the quality of a final product is guaranteed.

The invention relates to a preparation method and a preparation device of isocyanate, and the preparation method comprises the following steps: carrying out cold reaction on a phosgene solution and an amine solution in a cold reactor to obtain an intermediate mixed solution; separating the intermediate mixed solution by adopting a cyclone, obtaining a carbamoyl chloride mixed solution from an underflow port of the cyclone, and obtaining an amine hydrochloride mixed solution from an overflow port of the cyclone; the carbamyl chloride mixed solution enters a first thermal reactor for thermal reaction to obtain a first reaction product, and the amine hydrochloride mixed solution enters a second thermal reactor for thermal reaction to obtain a second reaction product; mixing the first reaction product and the second reaction product in a staying reactor to obtain an isocyanate reaction solution; and carrying out post-treatment on the isocyanate reaction liquid to obtain the isocyanate. The method can reduce the generation amount of urea by-products, further inhibits the generation of other subsequent by-products, reduces the chromaticity of the product, and improves the quality of isocyanate.

The invention discloses a synthesis method of allyl phosphonic acid diester. According to the method, phosphorous acid diester and an allyl chloride compound are used as raw materials and react in the presence of a specific transition metal catalyst and alkali under the conditions of normal pressure and 45-60 DEG C to obtain the allyl phosphonic acid diester. The method has the advantages of mild reaction conditions, simple operation, high product yield (90-99%), no by-product, no generation of halogenated alkane gas and easy industrial production, and is suitable for the fields of polymer flame retardants, electronic materials, pesticide and medicine intermediates and the like.

The invention discloses a method for improving the performance of clostridium aerovorans for synthesizing ethanol by utilizing gas fermentation. The method comprises the following steps: enabling the clostridium aerovorans to over-express ethanol synthesis pathway genes ald, adhE1 and adhE2; the expression of genes CLJU23220, CLJU25810 and CLJU25840 in the synthetic route of the 2, 3-butanediol is inhibited; and overexpressing acetic acid reuse genes aor1 and aor2. According to the clostridium yangdall engineering bacteria constructed by the method, the yield of ethanol synthesized by fermentation of synthesis gas is increased by 700% or above and reaches 1.70 g / L or above, and the synthesis amount of a by-product acetic acid is reduced by 18%.

The invention provides a treatment process of a byproduct sodium hypophosphite in a phosphorane preparation process, and aims to efficiently remove impurities and prepare a high-purity hypophosphorous acid product. The process comprises the following steps: carrying out small-volume sampling on reaction mother liquor, introducing carbon dioxide gas, and drawing an acidification curve of pH and conductivity; according to the plateau phase of an acidification curve, the CO2 flow rate and the pH value are controlled, step-by-step selective precipitation of impurities such as PO4 < 3->, HPO4 < 2->, Fe < 3 + >, AsO4 < 3-> and S < 2-> is achieved, and loss of a target component H2PO4 < 2-> is avoided; calcium hydroxide turbid liquid is introduced at a proper time to supplement Ca < 2 + > and promote efficient removal of phosphorus, arsenic and sulfur impurities; and subsequently removing excessive Na < + > and Ca < 2 + > through cation exchange, and concentrating to obtain a hypophosphorous acid product with the purity of more than or equal to 99.5%. The method is accurate in process control, thorough in impurity removal and good in repeatability and industrial adaptability, and the resource utilization efficiency of by-products and the added value of products are remarkably improved.

The invention belongs to the technical field of organic synthesis, and relates to a preparation method of 5, 5-dimethyl-4, 5-dihydroisoxazole. The method comprises the following steps: (1) reacting isopentenal with an oximation agent to obtain a reaction solution containing isopentenal oxime; (2) dropwise adding the reaction liquid into a mixture containing isopentenal and an acid catalyst for reaction to obtain a product; or when the reaction liquid contains water, performing phase splitting on the reaction liquid to obtain an organic phase, and dropwise adding the organic phase into a mixture containing the isopentenal and the acid catalyst for reaction to obtain a product. The method does not produce ketone by-products, and is good in atom economy, high in reaction yield, good in technological process continuity, low in cost, few in materials, simple to operate, mild in reaction condition, low in requirements on production equipment and suitable for large-scale industrial production.

The invention discloses low-odor thermoplastic vulcanized rubber for an automobile skin as well as a preparation method and application of the low-odor thermoplastic vulcanized rubber. The raw materials comprise 50 to 80 parts of ethylene-propylene-diene copolymer rubber, 20 to 50 parts of polypropylene, 5 to 15 parts of a compatilizer, 0.5 to 2.5 parts of a compound cross-linking agent, 0.5 to 2.0 parts of an odor adsorbent and 0.5 to 1.0 part of an antioxidant. The preparation method comprises the following steps: banburying and blending, dynamically vulcanizing by using a first double-screw extruder, adsorbing and deeply devolatilizing by using a second double-screw extruder, and carrying out vacuum baking at 100 DEG C. By utilizing the synergistic effect of the cross-linking agent and the assistant cross-linking agent, the degradation of polypropylene is inhibited while the cross-linking efficiency is ensured, and a low-boiling-point reaction by-product (tert-butyl alcohol) is thoroughly removed through a multi-stage devolatilization process, so that the problems that the traditional TPV material is strong in odor and easy to atomize are solved. The smell grade of the obtained material is less than or equal to 3.0 grade, and the atomization value is lt; and the coating is suitable for high-end automotive trim skins.

The invention discloses a dicarbonyl cyclopentadienyl cobalt complex as well as a preparation method and application thereof, and belongs to the technical field of organic metal synthesis. The preparation method of the dicarbonyl cyclopentadienyl cobalt complex specifically comprises the following steps: (1) dissolving cobalt octacarbonyl in carbon monoxide pre-saturated dichloromethane, and continuously introducing carbon monoxide gas for protection to obtain a reaction system; (2) dissolving cyclopentadiene in dichloromethane, and continuously introducing carbon monoxide gas for protection to obtain a cyclopentadiene solution; (3) adding a cyclopentadiene solution into the reaction system, heating and stirring for reaction; and (4) carrying out pressurized distillation and rectification on the reaction system. According to the invention, the carbon monoxide protective gas is introduced and the cyclopentadiene solution is prepared in the whole process to reduce the decomposition of the raw materials and reduce the generation of byproducts, so that the subsequent purification difficulty is reduced, and the reaction yield and the economic benefit of the product are improved.

The invention relates to the technical field of catalysts, and provides a catalyst and a preparation method thereof, and an application of the catalyst in carbon dioxide-based degradable plastics, the catalyst is a supported catalyst, and comprises a carrier and an active component; the carrier comprises ternary hydrotalcite, and the active component comprises double metal cyanide and a rare earth yttrium complex; the raw material of the double metal cyanide comprises a cyano coordination compound; the cyano coordination compound comprises potassium hexacyanomanganate and / or potassium hexacyanocobaltate. According to the technical scheme, the problems of low yield and more byproducts when the catalyst is used for catalyzing and preparing the carbon dioxide-based degradable plastic in the related technology are solved.

The invention provides a method for preparing hydrogenated bisphenol A by continuous catalytic hydrogenation of a fixed bed. The method comprises the following steps: step A, mixing and preheating a bisphenol A solution, a low-carbon amine additive and hydrogen in a gas-liquid mixing preheater to prepare a reaction material; step B, enabling the preheated reaction material to flow through a fixed bed reactor preloaded with a Ru-based catalyst, and carrying out catalytic hydrogenation reaction in the fixed bed reactor to generate a product material; step C, separating the product material through a gas-liquid separator to obtain a hydrogenated bisphenol A solution and hydrogen, and recycling the hydrogen; and rectifying the hydrogenated bisphenol A solution to obtain hydrogenated bisphenol A. The method provided by the invention effectively overcomes the defect that the single-batch reaction time of the existing catalytic hydrogenation process reaches 4-12 hours, and greatly shortens the continuous catalytic hydrogenation reaction time; by adding the low-carbon amine auxiliary agent, the reaction activity is promoted, and the generation of dehydroxylation byproducts is reduced; the selectivity of the product can be effectively guaranteed, the product is easy to separate, the safety is good, the cost is obviously reduced, and industrial application is easy.

The invention relates to the technical field of perfume production, in particular to a composite catalyst, a preparation method thereof and a synthesis method of ambergris. The composite catalyst disclosed by the invention is obtained by quaternizing porous silicon dioxide and then loading aluminum trichloride; when the composite catalyst is applied to synthesis of ambergris, the composite catalyst can be matched with potassium borohydride, so that sclareolide can be subjected to a one-step reduction reaction to generate ambergris, the reaction condition is mild, the method is stable, generation of sclareolide ring-opening byproducts is reduced, the product yield is increased, and the yield can reach 95% or above.

The invention belongs to the technical field of low-carbon dehydrogenation aids, and particularly relates to a heat balance aid as well as a preparation method and application thereof. The heat balance auxiliary agent comprises Al, Ca, Si, Cu and Mn elements existing in an oxide form; wherein the Al2O3, the CaO and the SiO2 jointly form a skeleton structure of the auxiliary agent, and the CuO and the MnO2 are used as active components and are attached to the skeleton structure; the molar ratio of metal elements in the heat balance auxiliary agent is as follows: Al: Ca: Si: Cu: Mn = (49-78.9): (15-25): (1-10): (5-15): (0.1-1). The heat balance additive prepared by the invention shows excellent anti-sintering capability, long service life and stable heat supply performance under harsh reaction conditions such as propane dehydrogenation, and can effectively improve the selectivity of target olefin and reduce the generation of byproducts such as methane.

The invention relates to the technical field of surfactants, and particularly discloses a preparation method and application of a sulfosuccinate type surfactant, and the preparation method specifically comprises the following steps: (1) esterification reaction: under the protection of inert gas, adding fatty alcohol and carboxylic acid anhydride, introducing gas for 10-20 minutes, adding a difunctional acidic site catalyst, heating to 95-105 DEG C, and reacting for 2-3 hours to obtain an esterification product; and (2) sulfonation reaction: cooling the esterification product to 70-80 DEG C, dropwise adding 20-40wt% of sulfonating agent aqueous solution, preserving heat for 1-2 hours after dropwise adding, and then performing post-treatment to obtain the sulfosuccinate type surfactant. In the preparation process, one-pot preparation is realized by regulating and controlling process conditions and developing a catalyst to efficiently catalyze esterification and sulfonation, intermediate products do not need to be separated between esterification and sulfonation, material loss caused by transfer and separation is avoided, the adopted catalyst can be used for inhibiting premature oxidation of a sulfur source in the sulfonation process, and the sulfonation efficiency is improved. The generation of byproducts is reduced, and the yield is improved.

The invention belongs to the technical field of organic synthesis, and particularly relates to an alkyl pentafluorosulfenyl compound and a preparation method and application thereof.The preparation method comprises the following steps that in the protective gas atmosphere, in a solvent, SF5Cl serves as a pentafluorosulfenyl source, an olefin compound serves as a reaction substrate and a free radical trapping agent, a thiol compound serves as a hydrogen source, and the alkyl pentafluorosulfenyl compound is obtained through a one-step reaction; under the action of an olefin additive, the alkyl pentafluorothio compound is constructed by a one-step method through a visible light-induced free radical process, and the olefin additive is used for inhibiting generation of a pentafluorothio chloride byproduct from a pentafluorothio source and an olefin compound. According to the method disclosed by the invention, a series of alkyl pentafluorosulfenyl compounds can be prepared by only needing olefin double bonds in substrates and selecting more substrates through the reaction, the reaction is simple, the reaction condition is mild, the reaction can be completed under visible light, the reaction time is short, the implementation is easy, and the method is suitable for industrial production. And a method support is provided for further screening the alkyl pentafluorosulfenyl compound with excellent biological activity.

The invention relates to the technical field of C9 heavy aromatics, in particular to a method and device for producing mesitylene from C9 heavy aromatics, and the method comprises the following steps: firstly, in the presence of a catalyst, mixing the C9 heavy aromatics with hydrogen, performing dealkylation isomerization reaction and dehydrogenation separation to obtain a liquid-phase product, and then performing two-stage separation on the liquid-phase product to obtain mesitylene. And mesitylene is produced to the maximum extent. The C9 heavy aromatics are subjected to selective dealkylation and trimethylbenzene isomerization reaction, and the obtained product does not contain propylbenzene, and the content of methyl-ethylbenzene is 1t; the method has the advantages that the yield of mesitylene is more than or equal to 0.2%, the interference of methyl ethyl benzene on the separation of the mesitylene is eliminated, the loss of the mesitylene is small, the one-way yield of the mesitylene is more than or equal to 12%, the reaction process is simple, the mesitylene and unsym-trimethylbenzene products are high in purity, the unsym-trimethylbenzene can be recycled to further increase the yield of the mesitylene, the process is flexible, byproducts are few, the product value is high, and the utilization value of C9 heavy aromatic hydrocarbon resources is obviously improved.

The invention provides a preparation method of 2-pentyl-2-cyclopentenone, and belongs to the technical field of organic synthesis. The preparation method comprises the following steps: carrying out a first-stage isomerization reaction on 2-pentylidene cyclopentanone and a first composite catalyst in a first atmosphere to obtain an intermediate, carrying out a second-stage isomerization reaction on the intermediate and a second composite catalyst in a second atmosphere, and controlling the volume ratio of nitrogen to hydrogen in the first atmosphere and the second atmosphere to obtain the 2-pentylidene cyclopentanone. In the first-stage isomerization reaction, the conversion rate of converting 2-pentylidene cyclopentanone into 2-pentyl-2-cyclopentenone is increased, and in the second-stage isomerization reaction, the use amount of hydrogen in the second atmosphere is reduced, the temperature of the second-stage isomerization reaction is increased, generation of by-products is inhibited, and the yield of 2-pentylidene cyclopentanone is increased. Further, the yield and the purity of the 2-pentyl-2-cyclopentenone can be improved. According to the preparation method, the first-stage isomerization reaction and the second-stage isomerization reaction are continuous reactions, intermittent reactions are not needed, and the preparation method is more suitable for industrial application.

The invention relates to the technical field of removal of carbon dioxide in oil gas, in particular to a preparation method of carbon dioxide PAMAM grafted ionic liquid for oil gas purification. Comprising the following steps: 1) activating carboxyl: dissolving 1-butyl-3-methylimidazole carboxylic acid in a solvent, adding dicyclohexylcarbodiimide and 4-dimethylaminopyridine, and stirring at room temperature to generate active ester; 2) grafting PAMAM: adding PAMAM dendrimer into the solution, and reacting under the protection of nitrogen; and 3) purification: removing the dicyclohexylurea precipitate through centrifugation, and dialyzing the filtrate to remove the unreacted ionic liquid and small molecule byproducts to obtain the PAMAM grafted ionic liquid. The stability and durability of the absorbent are remarkably improved, the CO2 absorption efficiency is improved, the energy consumption of the absorbent per unit mass is reduced, and the preparation method is simple and controllable, mild in reaction condition and easy for large-scale production.

The invention provides a green and efficient production method of hexafluoropropylene oxide, and belongs to the technical field of synthesis of organic fluorine compounds. The method comprises the following steps: carrying out a continuous oxidation reaction on hexafluoropropylene, oxygen and a perfluoro solvent in an immersed supergravity reactor to generate HFPO and byproducts carbonyl fluoride and trifluoroacetyl fluoride, removing the solvent from the reacted liquid, feeding the liquid into an acyl fluoride rectifying tower, separating low-boiling-point acyl fluoride from the tower top, enriching HFPO, unreacted HFP and a small amount of acyl fluoride from the tower bottom, and carrying out a continuous oxidation reaction on the HFPO and the byproducts carbonyl fluoride and trifluoroacetyl fluoride. Converting acyl fluoride into anhydrous trifluoroacetic acid from a high-boiling-point substance at the bottom of the tower through a hydrolysis tower, carrying out alkali washing on the synthesis gas to obtain an HFPO crude product, and further carrying out drying and extractive distillation to obtain an HFPO product; acyl fluoride rectified by an acyl fluoride rectifying tower is directly used for producing PAVE, and long-chain perfluoroacyl fluoride accumulated in a solvent of oxidation reaction is hydrolyzed to synthesize a non-PFOA emulsifier. The method has the advantages of high HFPO selectivity, short reaction time and high safety; the method realizes resource comprehensive utilization of byproducts, and is environment-friendly and economical.

The invention relates to the field of benzoxazine, in particular to modified benzoxazine resin and a preparation method and application thereof.The preparation method of the modified benzoxazine resin comprises the following steps that S1, first-stage reaction is conducted, specifically, an alkane amine compound, formaldehyde and an organic solvent are stirred to be uniform and heated to react; the alkane amine type compound is one or more of short aliphatic chain amine, alicyclic polyamine and a monoamine type compound; s2, second-stage reaction: adding a phenolic compound containing unsaturated alkyl, and heating for reaction; s3, heating, and removing small molecular impurities and by-products under negative pressure to obtain the modified benzoxazine resin, the modified benzoxazine resin and the preparation method and application thereof solve the problem that the existing benzoxazine resin is insufficient in storage stability and processing performance while improving the dielectric property.

The invention provides a preparation method of ethylene carbonate and ethylene sulfate, which comprises the following steps: 1) by taking vinylethylene carbonate as a raw material, carrying out oxidation reaction with an oxidant to obtain epoxy ethylene carbonate as shown in a formula I; and 2) carrying out heating reaction on the epoxy ethylene carbonate as shown in the formula I obtained in the step 1) and sulfamic acid in an acidic solvent to obtain ethylene carbonate disulfate as shown in a formula II. The method avoids the problem of poor reaction selectivity caused by using butantetraol as a raw material in the prior art; according to the method disclosed by the invention, an intermediate butantetraol carbonate is not generated, so that the problem that the intermediate further reacts to generate a byproduct 2, 4, 7-trioxa-3-oxy-bicyclo [3.3. 0] octane does not exist; in addition, when the final product sulfate is synthesized, mild and non-irritant sulfamic acid is used, and the method has the advantages of being clean, green and environmentally friendly.

The invention discloses an environment-friendly early-strength alkali-free accelerator as well as a preparation method and application thereof, and belongs to the technical field of concrete admixtures. When the environment-friendly early-strength alkali-free accelerator is prepared, aluminum sulfate is not directly adopted to participate in the reaction, the accelerator is obtained by reacting concentrated sulfuric acid and fluosilicic acid with an aluminum oxide component in the industrial byproduct aluminum mud, and the solubility of aluminum ions is further improved by utilizing the principle that concentrated sulfuric acid releases a large amount of heat when encountering water and the principle that acid-base reaction releases heat; the resource utilization of the industrial byproduct aluminum mud is realized. According to the invention, the industrial by-product fluorosilicon slag is subjected to mechanical activation and chemical excitation and the synergistic effect of the grinding aid, so that the reaction activity of the fluorosilicon slag is greatly improved, the fluorosilicon slag is used for preparing the accelerator, the effects of accelerating and early strength are exerted, waste is turned into wealth, and the raw material cost of the accelerator is saved.