30results about How to "High reaction conversion rate" patented technology

The invention belongs to the technical field of synthesis and preparation of aluminum nitride, and discloses a controllable and extensible preparation method of a one-dimensional aluminum nitride nanowire / nanotube, which comprises the following steps: (1) uniformly mixing a solid aluminum source and a solid nitrogen source, transferring the mixture into a rotatable crucible, transferring the crucible into a tubular furnace, sealing the tubular furnace, and carrying out heat preservation for 2-3 hours; vacuumizing and then introducing protective gas; (2) under the condition that protective gas is continuously introduced, the tubular furnace is heated to a preset target temperature for a nitridation reaction, and the nitridation reaction is carried out under the condition that a crucible rotates at a constant rotating speed; and after the reaction is finished, cooling the tubular furnace and stopping the rotation of the crucible to obtain a one-dimensional aluminum nitride nanowire or nanotube product. According to the method, the solid aluminum source and the solid nitrogen source are used as raw materials, and the crucible rotation is introduced during the nitridation reaction to carry out dynamic enabling improvement, so that the single-crystal aluminum nitride nanowire or nanotube with high purity and uniform morphology can be efficiently synthesized.

The invention provides a novel method for obtaining (4)-(4-cyano-2-methoxyphenyl)-5-ethoxy-2, 8-dimethyl-1, 4-dihydro-1, 6-naphthyridine-3-carboxylic acid (intermediate 5) and an optical isomer (intermediate 5a) thereof through hydrolysis of a fenerenone intermediate III or an optical isomer IIIa thereof, the method does not need to use CuCl2, and the method is simple in operation, easy to implement and low in cost. By controlling the dosage ratio of acid to the initial raw material, or the dosage ratio of Zn powder to the initial raw material, or optimizing reaction conditions, the conversion rate of the intermediate III or intermediate IIIa is unexpectedly improved (not less than 90%), the generation amount of intermediate impurity X is reduced (not more than 5%), the generation of experimental waste acid is reduced from the source, the product purity is also improved, and the production cost is reduced. The method is suitable for industrial large-scale production.

The application provides a method for synthesizing 3-methyl-2-buten-1-ol, and belongs to the technical field of isopentenol synthesis. The method comprises the following steps: introducing 3-methyl-3-buten-1-ol and an atmosphere containing hydrogen into a fixed bed reactor, and performing a hydrogenation isomerization reaction under the action of a Pd / Al2O3 catalyst to generate 3-methyl-2-buten-1-ol; wherein the content of formaldehyde in the 3-methyl-3-buten-1-ol is 0.03-0.15%. The application adopts a fixed bed reactor to perform continuous production, adopts a Pd / Al2O3 catalyst with low palladium content as the catalyst, the preparation method is simple, the price is relatively low, and the content of formaldehyde in the 3-methyl-3-buten-1-ol is controlled to inhibit a side reaction, so that the reaction conversion rate and the product selectivity are high.

The invention relates to the field of high polymer materials, in particular to a method for adjusting material performance by controlling a polymer sequence structure, which adopts an organic tellurium mediated free radical polymerization mode, selects a first monomer and a second monomer with glass transition temperature difference, and keeps the equivalent proportion unchanged. The sequence structure of the polymer is regulated and controlled through a random copolymerization mode and a block copolymerization mode respectively, so that the polymer with corresponding material performance is realized; the conversion from plastic to rubber can be realized through sequence structure regulation and control; the material performance, including flexibility, elasticity, processability and surface responsiveness, is remarkably improved. The method disclosed by the invention is suitable for application scenes with high requirements on fine structure-performance matching, such as thermoplastic elastomers, functional films and intelligent response coatings, is high in reaction conversion rate and excellent in atom economy, and has an industrialization prospect.

The application belongs to the field of pharmaceutical preparations and discloses a soothing pharmaceutical preparation and a preparation method thereof. The preparation method comprises the following steps: firstly, preparing synthetic naphazoline hydrochloride by using compound 1 containing a cyano group, wherein a composite solvent composed of toluene and ethyl acetate is used for condensation reaction in the synthesis process, and dilute hydrochloric acid is used for salt formation; secondly, preparing synthetic pheniramine maleate by using compound 2 containing a halogen group and compound 3 containing a cyano group, wherein a weak base catalyst is used for condensation reaction in the synthesis process; finally, adding functional additives, naphazoline hydrochloride and pheniramine maleate into water, stirring and dissolving, and filling to obtain the soothing pharmaceutical preparation, wherein the pH of the soothing pharmaceutical preparation is 5.7-6.3. The soothing pharmaceutical preparation prepared by the above method can effectively avoid the adverse influence of impurities in naphazoline hydrochloride and pheniramine maleate on the soothing effect.

The application discloses a spinel structure Cu 0.5 Co 0.5 Al2O4 catalyst and a method for catalytically preparing o-nitrobenzaldehyde, and belongs to the field of chemical synthesis. The method uses o-nitrobenzyl alcohol as a raw material, dissolves the raw material in an organic solvent, uses spinel structure Cu 0.5 Co 0.5 Al2O4 as a reaction system catalyst, adds TEMPO as a cocatalyst, and reacts in a fixed bed under the condition of oxygen being introduced. After the reaction is completed, the reaction system is cooled to normal temperature, is dissolved, and then a crude product is obtained. The conversion rate of the reaction is 100%, and the selectivity is 98.9%. The crude product is purified through recrystallization of n-hexane, and then o-nitrobenzaldehyde is obtained. The product has a gas phase purity of 99.95%. The spinel structure Cu 0.5 Co 0.5 Al2O4 spinel catalyst has high catalytic activity and high catalytic stability, and has recycling usability, and therefore provides an efficient, economical and green and environment-friendly synthesis method for o-nitrobenzaldehyde.

The utility model relates to a chemical industry mechanical equipment field especially, relates to a kind of ester exchange equipment for vegetable oil-based emulsifier production, including tank body, the tank body top is equipped with feed inlet, tank body bottom is equipped with discharge gate, the temperature regulating system is arranged in the tank body;The tank body top is installed with stirring motor, the output shaft of stirring motor is connected with stirring shaft, the stirring shaft is provided with stirring vane, the stirring vane includes the helical stirring vane of top layer, the stirring vane of pulp of middle layer and the anchor stirring vane located in bottom layer;The temperature regulating system includes high temperature layer located at the tank body top, constant temperature layer located at the tank body middle and cooling layer located at the tank body bottom.The ester exchange equipment of the application can reduce the adhesion of material to the inner wall of equipment and stirring device during production, thereby improving the uniformity of material distribution, reaction conversion rate and the quality of final product.

This application relates to a silicon nitride magnesium powder, its preparation method, and its applications, belonging to the technical field of structural ceramic powder materials. The preparation method includes: embedding silicon nitride powder into magnesium powder to form a magnesium-based composite powder with a micro / nano composite structure on its surface; mixing the magnesium-based composite powder with a dispersant to obtain a reaction precursor; subjecting the reaction precursor to a self-propagating synthesis reaction to obtain the silicon nitride magnesium composite powder; and sequentially subjecting the silicon nitride magnesium composite powder to acid washing and calcination treatments to obtain the silicon nitride magnesium powder. The prepared silicon nitride magnesium has a yield of over 95%, an oxygen content of less than 0.15 wt.%, and a particle size controlled between 1 μm and 2 μm with uniform distribution; it is suitable for applications such as a sintering aid for high-performance ceramics, a component of refractory materials, and a reinforcing phase in metal matrix composites.

This invention discloses a phase transfer enrichment functional catalyst for the preparation of 3-hydroxypropional from acrolein hydration, its preparation method, and its application, relating to the field of catalyst technology. Using macroporous styrene-based resin as a support, this invention introduces an intermediate containing dichlorinated active sites through a Friedel-Crafts phosphorylation reaction between phosphorus oxychloride and the resin surface. Subsequently, through stepwise esterification and hydrolysis reactions, organophilic long chains and phosphate hydroxyl functional groups are introduced, respectively, constructing a microenvironmental catalytic system with synergistic effects of organophilic side chains and acidic centers, thereby improving the conversion rate and selectivity of the acrolein hydration reaction.

The invention relates to the technical field of hexafluoropropylene rectification post-treatment, and discloses a method for recovering fluoroether from hexafluoropropylene rectification raffinate, and the method comprises the following steps: S1, mixing hexafluoropropylene rectification raffinate with alcohol, and carrying out reactive rectification to obtain a fluoroether-containing mixture and reactive rectification mixed gas; s2, carrying out first rectification on the fluorine-containing ether mixture to obtain a fluorine ether-alcohol azeotrope; and S3, extracting the fluoroether-alcohol azeotrope to obtain a fluoroether crude product, and carrying out second rectification on the fluoroether crude product. According to the present invention, the reaction rectification technology is adopted to reinforce the etherification reaction of the hexafluoropropylene rectification residual liquid and the alcohol, and the reaction product is timely separated during the chemical reaction, such that the reaction conversion rate is substantially improved, the reaction heat is efficiently utilized, and the conversion rate of the highly toxic octafluoroisobutene and the fluoroether yield are significantly increased. Reactive rectification, first rectification, extraction and second rectification are effectively integrated, and a fluoroether product with the purity being larger than 99% is obtained.

The application relates to the technical field of organic synthesis, in particular to a preparation method of C9H 12 O. The method is to use phenol and isopropyl alcohol as reaction raw materials, then heat under a protective atmosphere, and make the mixed reaction liquid pass through the surface of a catalyst to complete the reaction and obtain C9H 12 O. In the process, when the catalyst is a phosphate catalyst, isopropyl phenol is mainly synthesized; when the catalyst is an Al-P-O catalyst, ortho-isopropyl phenol and para-isopropyl phenol are mainly synthesized. The reaction has low preparation cost, is not easy to produce harmful substances, is an environmentally-friendly reaction path, and realizes green environmental protection and low cost of C9H 12 O production.

This invention relates to the field of chemical synthesis, and more particularly to a process for producing allyl diethylene glycol dicarbonate, comprising the following steps: using allyl alcohol and dimethyl carbonate as raw materials, a transesterification reaction is carried out under the action of a core-shell catalyst to produce dipropylene carbonate; after solid-liquid separation and vacuum distillation to recover methanol and dimethyl carbonate, a second transesterification reaction is carried out with diethylene glycol under the same catalyst to produce allyl diethylene glycol dicarbonate; finally, high-purity product is obtained by multi-stage vacuum distillation purification. The core-shell catalyst uses MCM-41 molecular sieve as a support, with an amino-modified and zirconium-ion-coordinated core, encapsulated by an interface layer and a phenyl-modified silica shell, exhibiting high activity, high selectivity, and excellent structural stability. This process is mild, the catalyst is recyclable, and the product yield is high with excellent purity, making it suitable for industrial production.

The invention provides an acrylic resin composition, a preparation method thereof and an optical-grade resin molded body. The acrylic resin composition comprises (methyl) acrylic resin A and imide resin B, (methyl) acrylic resin A is used as raw material resin, an amination reagent is added for amination modification, and the carboxyl content in a polymer is reduced, so that the dimensional stability and the water vapor barrier property of the resin in a humid and hot environment are improved on the basis of keeping the heat resistance of the resin. In addition, an amide reaction which is lower in reaction activation energy and easier to react is adopted to replace an amine-ester exchange reaction, so that the energy consumption in the modification reaction process is reduced, and the reaction conversion rate is increased.

The invention relates to a method for preparing lithium sulfide through a sulfur-lithium salt reaction assisted by molten salt, and belongs to the technical field of lithium-sulfur batteries and solid electrolyte materials, and the method comprises the following steps: 1, carrying out mechanical crushing and screening treatment on a lithium salt; then putting the treated lithium salt and molten salt into a crucible, and uniformly mixing; 2, putting the crucible filled with the lithium salt and the molten salt in the step 1 into a reactor; 3, in an inert atmosphere or a reduced pressure atmosphere, sulfur is added into the reactor, so that the sulfur is molten under the action of the molten salt and permeates to the surface of the lithium salt, and the sulfur and the lithium salt react at an interface to generate lithium sulfide; and 4, cooling the system after the reaction to room temperature in an inert atmosphere or a reduced pressure atmosphere, taking out the product, and separating and recovering the residual fused salt to obtain lithium sulfide powder. The method is simple in process and environment-friendly, and the prepared lithium sulfide has the advantages of high purity, low defect, cubic phase and the like, and is suitable for industrial amplification.

The application provides a synthesis process of hexamethyldisilazane. The synthesis process comprises the following steps: adding trimethylchlorosilane into liquid ammonia, then performing high-pressure stirring reaction to obtain a reaction liquid; performing layer separation, and performing rectification on the lower layer of the reaction liquid to obtain hexamethyldisilazane; performing pressure relief on the upper layer of the reaction liquid, and ammonia gas is generated after the liquid ammonia is vaporized, and ammonium chloride solid is precipitated; performing reduced-pressure drying on the ammonium chloride solid, desorbing the ammonia gas adsorbed on the ammonium chloride, and obtaining refined ammonium chloride. The reaction does not need to add any solvent, the reaction rate is adjusted by controlling the dropping speed of trimethylchlorosilane, and the generated by-product ammonium chloride is completely dissolved by controlling the addition amount of liquid ammonia, so that the mass and heat transfer effects of the reaction are ensured, the product conversion rate is improved, the reaction time is shortened, and the product is easy to separate. The method avoids the use of solvent, generates less waste liquid, is green and environmental protection, and is low in cost.

The invention provides a nano ZSM-5 molecular sieve and a preparation method thereof. The preparation method comprises the following steps: mixing a first silicon source, a first aluminum source, inorganic alkali, water and amorphous molecular sieve pre-crystallization liquid, and aging to obtain a first raw material mixture; adding a second silicon source into the first raw material mixture to obtain a second raw material mixture, crystallizing, filtering, washing, drying and roasting to obtain the nano ZSM-5 molecular sieve, the second silicon source comprises white carbon black. The invention also provides the nano ZSM-5 molecular sieve obtained by the preparation method. The nano ZSM-5 molecular sieve provided by the invention has the characteristics of small crystal grain, large specific surface area and abundant mesopores and macropores.

This invention discloses a gas-liquid mass transfer unit, comprising: an upper tray channel extending downward from an opening in the upper tray; a swirl vane array at the top of the upper tray channel, with a first through-hole on the channel wall at a fixed position of the swirl vanes, for allowing only gas phase flow during the gas phase flow stage, forming a swirling flow through the swirl vane array, and for allowing only liquid phase flow during the liquid phase flow stage; a first constriction at the bottom of the upper tray channel, with a second through-hole along the upper edge of the first constriction for liquid phase overflow; a lower tray channel with a third through-hole at its upper part, for allowing only gas phase flow during the gas phase flow stage and only liquid phase flow during the liquid phase flow stage; a fourth through-hole in the lower middle part of the lower tray channel; a second constriction at the top of the lower tray channel; and a movable component that can slide entirely within the upper and lower tray channels; the movable component includes an upper circular surface and a lower circular surface fixedly connected; when the movable component moves to the top under the lifting action of the gas phase, it is in the gas phase flow stage; when the movable component moves downward under the gravity action of the liquid phase, it is in the liquid phase flow stage.

The application discloses a kind of gas-liquid two-phase mixing type reaction kettle for pharmaceutical intermediates production and drive control method, it is related to pharmaceutical intermediates production equipment technical field.In the application: the bottom of reaction kettle is equipped with gas inlet end, inner cavity is configured with driving shaft and stirring paddle, top cover is configured with gas concentration sensor and multiple inverted cone, and inner cavity is provided with floating mixing disc.The piston ring is arranged on the side of floating mixing disc, the main shaft sleeve and the flow guide pipe are arranged on the top of floating mixing disc, the jet nozzle is arranged on the top end of flow guide pipe, and the liquid outlet of jet nozzle is opposite to the lowest point of inverted cone.The floating mixing disc is provided with flow guide slope and flow guide channel, the flow blocking component is elastically installed at the flow guide channel, a liquid level meter is further arranged, and the reaction kettle is provided with a hydraulic system for driving the floating mixing disc to rise and fall.The application realizes efficient mixing of gas-liquid two-phase by dynamically controlling the rising and falling of floating mixing disc, improves reaction efficiency and product quality, and is suitable for gas-liquid two-phase reaction production of pharmaceutical intermediates.

The invention relates to a method for regulating and controlling residence time of particles with different particle sizes in a multi-chamber fluidized bed reactor and inhibiting backmixing of particles among chambers, which can realize regulation and control of residence time of particles with different particle sizes in a fluidized bed. The multi-chamber fluidized bed reactor comprises an air inlet (1), an air chamber (2), a distribution plate (3), fluidization chambers (4), a feed port (5), an expansion section (6), an air outlet (7), a discharge port (8), an internal component inlet (9), an internal component outlet (10), n elutriation internal components (11) and an elutriation internal component gas inlet (12). A fluidized bed air inlet (1) is connected to the air chamber (2), an air outlet (7) is located at the top of the fluidized bed, a feeding port (5) is connected to the upper portion of the leftmost fluidization bin, and a discharging port (8) is connected to the middle of the rightmost fluidization bin. According to the invention, the residence time of particles with different size fractions in the fluidized bed can be regulated and controlled, and meanwhile, backmixing of particles between adjacent chambers can be approximately completely inhibited.

The present application relates to a kind of catalyst for propylene, butene oligomerization reaction and its preparation method and application, belong to catalyst technical field.The technical problems such as expensive, reaction conversion rate is low, harsh condition, easy argillization, corrosive to equipment etc. in prior art for olefin oligomerization reaction catalyst are solved.The catalyst of the present application includes 70wt%-80wt% main catalyst, 2wt%-3wt% cocatalyst and 18wt%-27wt% binder;Wherein, main catalyst is molecular sieve, cocatalyst is metal oxide, and binder is alumina.The catalyst is used to catalyze propylene or butene to carry out oligomerization reaction, has high propylene and butene reaction conversion rate (conversion rate >85%), high dimer and trimer selectivity (selectivity >80%), long single-pass use cycle, good sulfur resistance, easy to separate and the like, in addition, the preparation method of the catalyst is simple, and applicability is strong.

This invention belongs to the field of lubricating oil technology and discloses a method for synthesizing isopropylnaphthalene and its application. The method for synthesizing isopropylnaphthalene includes reacting a naphthalene source and an alkylating agent under an inert atmosphere and in the presence of a composite catalyst to obtain isopropylnaphthalene; the composite catalyst is a molecular sieve and SO4 supported on the molecular sieve. 2‑ Based on the mass of the composite catalyst being 100%, the SO4 2‑ The mass fraction is 2% to 11%; the composite catalyst of the present invention uses SO4 2‑ Loaded on a molecular sieve support, on the one hand, SO4 2‑ The combination of the superacid properties and the high specific surface area and certain pore structure of the molecular sieve can provide more acidic sites. The resulting composite catalyst exhibits high reaction conversion rate and selectivity for diisopropylnaphthalene in the naphthalene / 2-isopropylnaphthalene and propylene isopropylation reactions.

The application discloses a device and a method for recovering sulfur by hydrogen sulfide thermal catalytic cracking, belongs to the technical field of hydrogen sulfide catalytic cracking, and comprises successively connected gas inlet devices, hollow reaction tubes, condensers and sulfur collecting devices. The hollow reaction tubes are arranged in heating furnaces, heat preservation structures are arranged outside connecting pipelines of the hollow reaction tubes and the condensers, inverted catalyst placing tubes are arranged in the hollow reaction tubes, a plurality of through holes are formed in the bottom of each catalyst placing tube and are communicated with the upper space of the hollow reaction tube, different catalysts are respectively filled in the inside of each catalyst placing tube and the upper space of the hollow reaction tube. The application can realize controllable bed layer height of the catalyst, controllable proportion of the two kinds of catalysts and space separation, effectively recovers the sulfur, avoids the occurrence of sulfur blockage, and simultaneously improves the hydrogen sulfide reaction conversion rate and the total sulfur recovery rate.

The utility model relates to the technical field of preparation of diethylene glycol monoethylene diether, and particularly discloses a dissolving device for preparation of diethylene glycol monoethylene diether, which comprises a tank body, a discharge pipe arranged at the bottom of the tank body and provided with a discharge valve, and a top cover arranged at the top of the tank body, a pressure release valve, a pressure sensor, a dropper, a PH probe and an oxygen concentration analyzer are integrated at the top of the top cover, a liquid outlet of the dropper, the pressure sensor, the PH probe and a detection probe of the oxygen concentration analyzer all extend into the tank body, and a stirring mechanism is combined with a crushing cutter, so that uniform mixing of a high-viscosity material and low-boiling-point vinyl ether is realized, the reaction is accelerated, and the reaction efficiency is improved. Microbubble groups generated by the annular nitrogen distribution pipe are combined to enhance liquid turbulence, improve the reaction conversion rate and reduce by-products, and a pressure release valve, a pressure sensor and oxygen concentration real-time monitoring are combined, so that the oxygen concentration in the tank is kept stable, and the risk of burning explosion is completely eradicated.

The invention relates to the technical field of medicine synthesis, and discloses a synthesis method of tiall peptide, which comprises the following steps: carrying out amino protection on Trp15, Lys20 and Ile23 on polypeptide with a sequence of SEQ ID NO: 1, sequentially activating and amidating carboxyl at a C terminal, and removing a protecting group on the amino to obtain TP07; the preparation method comprises the following steps: grafting TP11 to an amino group of Lys20 in TP07 to obtain TP08; carrying out condensation reaction on an N-terminal amino group (namely, an amino group on Ile23) in TP08 and a carboxyl group in TP12, and removing a protecting group to obtain the tiall peptide. According to the present invention, during the synthesis process of the tilpotide, through the whole synthesis route and the design of the process details, the generation of the by-products can be reduced, the high reaction conversion rate and the high yield can be achieved, the purification difficulty of the product can be reduced, and the prepared tilpotide has the high purity.

The present application relates to a kind of continuous discharge reaction kettle unit of pseudo-boehmite, belong to inorganic material synthesis equipment technical field;Including stepped main reactor, the stepped main reactor is in vertical direction and presents stepped variable-diameter structure, at least including first stage reaction section and second stage reaction section from top to bottom, the top of the stepped main reactor is equipped with the feed inlet being connected with the discharge port of the premixing unit, the stepped main reactor is equipped with boost system, the stepped variable-diameter structure cooperates boost system and is synergistically regulated slurry flow rate and residence time;By variable-diameter structure, material flow cross section is changed, gradient flow rate and uniform turbulent flow field are formed, cooperate boost system active flow guide and push, accurately regulate slurry flow rate and each stage residence time, completely solve the problem of traditional equipment flow field disorder, short circuit flow, dead zone, inhibit solid slurry settlement and plugging failure from root, substantially improve the stability of equipment continuous operation.

The utility model relates to the technical field of hydrolysis tanks, in particular to an agriculture and forestry solid waste lignin hydrolysis tank with a spiral stirring structure, which comprises a hydrolysis tank body, and a left servo motor and a right servo motor which are mutually symmetrical are fixedly mounted at the top of the hydrolysis tank body. The tail end of an output shaft of the servo motor is connected with a long shaft which is vertically arranged and extends into the hydrolysis tank body through a coupler, a spiral stirring blade in a spiral shape is fixedly mounted on a rod body of the long shaft located in the hydrolysis tank body, and an attaching ring is fixedly mounted on a rod body at the bottom end of the long shaft; a horizontal supporting rod is fixedly installed on the inner wall of the bottom of the hydrolysis tank body, a left supporting ring and a right supporting ring which are mutually symmetrical are fixedly installed on the top face of the horizontal supporting rod, annular grooves are formed in the supporting rings, a rod body at the bottom end of the long shaft is located in the annular grooves and rotationally connected with the annular grooves, and the upper surfaces of the supporting rings are covered with attaching rings. The reaction kettle disclosed by the utility model is convenient for stirring operation, has better stability and is beneficial to hydrolysis operation.

The application discloses a high-boiling chlorination furnace and a high-boiling substance treatment system, which are used for uniformly mixing chlorine gas and gas-phase high-boiling substances in the high-boiling chlorination furnace and improving the situation that the gas-phase high-boiling substances appear condensation and block the gas inlet pipeline of the chlorine gas. The high-boiling chlorination furnace comprises a furnace body (1), a gas distributor (2), a first porous medium (4), a gas premixing cavity (5) and a high-boiling inlet device (3). The gas distributor (2) is fixed at the bottom of the furnace body (1). The first porous medium (4) is arranged in an inner cavity and located above the gas distributor (2). The gas premixing cavity (5) is located above the first porous medium (4). There is a gap between the gas distribution plate (6) and the first porous medium (4), the part of the inner cavity between the gas distribution plate (6) and the first porous medium (4) forms the gas premixing cavity (5). The high-boiling inlet device (3) is fixed at the bottom of the furnace body (1).

The application provides a preparation method of hexanediol bis[3-3,5-di-tert-butyl-4-hydroxyphenyl]propionate, comprising the following steps: step one, adding 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propyl methyl ester, 1,6-hexanediol and immobilized lipase Novozym435 into a reaction kettle, filling CO2, and performing enzyme catalysis transesterification reaction in a supercritical CO2 state; step two, filtering the reaction liquid in step one, recycling and repeatedly using the filter cake which is the catalyst immobilized lipase Novozym435, and performing column chromatography treatment on the filtrate; step three, according to the separation conditions of each component in the reaction liquid sample in step one in thin layer chromatography or liquid chromatography, combining the target collection liquid in the column chromatography process and removing the solvent again; combining and removing the solvent of other collection liquids, and repeatedly participating in the reaction of the remaining substances; and step four, drying the remaining substances of the target collection liquid in step three to obtain a target product.

This invention provides a palladium catalyst, its preparation method, and a method for preparing an all-trans C15 phosphine salt. The method prepares a pyrazole-palladium catalyst, which is then used in the isomerization reaction of a C15 phosphine salt to obtain the all-trans C15 phosphine salt. The catalyst of this invention has advantages such as high catalytic conversion efficiency and good selectivity.

This invention belongs to the field of acyclic compound technology, specifically relating to a method for preparing tert-butyl peroxide. An alkaline solution is added to acetic anhydride, and the mixture is stirred to obtain a reaction solution. A composite catalyst is added to a purified tert-butyl hydrogen peroxide solution, and the mixture is stirred to obtain a mixture. The reaction solution is added to the mixture, and the mixture is stirred to obtain an organic phase. The organic phase is acid-washed to obtain an oil phase. The oil phase is then alkali-washed, salt-washed, and freeze-dried to obtain tert-butyl peroxide. This invention purifies the tert-butyl hydrogen peroxide solution, effectively removing di-tert-butyl peroxide impurities. A composite catalyst composed of p-toluenesulfonic acid, perfluorosulfonic acid resin, and sulfonated carbon is used as the catalyst, reducing the destructive effect on the product tert-butyl peroxide and significantly improving the yield of tert-butyl peroxide, thus possessing industrial production significance.