46results about How to "High synthetic conversion rate" patented technology

A low-free radical TDI polyurethane curing agent, its production and product are disclosed. The process is carried out by putting tolylene-diisoester cyanate, solvent S and catalyst A into reactor, adding into antioxidant and long-chain alcohol, agitating in reactor, heating, keeping temperature, inspecting NCO value, adding into phase-transferring solvent X while reaching NCO value to 20-40%, adding into catalyst B till reaching NCO value to 10-15, adding into inhibitor to stop reaction, adding into solvent S, decreasing pressure, distilling and removing phase-transferring solvent X. It's cheap and convenient.

The invention discloses a new method of chloroethylene through acetylene method and specific equipment, which comprises the following steps: disposing raw material gas strictly; reacting two-segment compensation; recycling heptane; cooling; radiating; providing specific catalyst and reactor to synthesize chloroethylene; disposing effluent with mercury to obtain high-purity chloroethylene monomer.

The invention discloses an insoluble sulfur stabilizing agent and a preparation method thereof. The insoluble sulfur stabilizing agent has a chemical structural formula as shown in the specification, and the molecular weight is 218-465, wherein R is C2-C20 linear-chain or branched-chain alkoxy or amino; and the stabilizing agent is generated through reaction by using an organic acid salt and an oxidant as raw materials and using water, acetone or fatty alcohol as a reaction medium. The stabilizing agent can be applied to an insoluble sulfur production process, can be uniformly dispersed in insoluble sulfur, can greatly improve the high-temperature stability of insoluble sulfur, and has the characteristics of mild process conditions, available raw materials, low synthesis cost, high product yield and the like.

The invention belongs to the field of urea preparation, and particularly relates to an energy-saving urea production system and a production process thereof. The system comprises a CO2 compressor, an ammonium carbamate pump, a liquid ammonia pump and a urea synthesizer. The system is characterized in that the CO2 compressor is connected with the ammonium carbamate pump and the liquid ammonia pump, the liquid ammonia pump is connected with the urea synthesizer, a falling-film countercurrent medium-pressure decomposing tower and a heater, an ammonium carbamate condenser, an ammonium carbamate separator, a three-stage medium-pressure absorption tower and an evaporative ammonia refrigeration recoverer, a liquid ammonia buffer tank, an inert gas scrubber, a tail-gas ammonia cleaning fine purifier, a low-pressure decomposing tower and a heater, a dimethyl liquid preheater, a horizontal low-pressure absorber, a falling film type pre-evaporator, a one-stage evaporator and a one-stage evaporative condenser, a two-stage evaporator and a two-stage evaporative condenser, and a process wastewater desorption and hydrolysis tower are sequentially connected behind the urea synthesizer in sequence. The energy-saving urea production system has the advantages of low investment, low energy consumption, simple operation, high elasticity and the like, thereby the process technology has considerable economic benefit and social benefit.

The invention relates to a manufacturing process of methanol and in particular to a method for synthesizing methanol through a low-carbon technology. The method is characterized by comprising the following steps: mixing synthesis gas transformed from methane gas and the synthesis gas produced by coal gasification in proportion, performing a synthesis compression process on the mixed gas, and then enabling the mixed gas to enter into a methanol reactor for producing the methanol, wherein the methane gas is natural gas or oil-associated gas or coal bed gas or coke oven gas or blast furnace gas or oil refining dry gas and other CH4-rich mixed gas; the hydrogen-carbon ratio or the ratio of H:C is the proportion of (H2-CO)/(CO+CO2) in the synthesis gas, and H2, CO and CO2 gas components are calculated by percentage content; and the production of the synthesis gas by coal gasification comprises the production of raw gas and the regulation process of the hydrogen-carbon ratio. The method for synthesizing the methanol through the low-carbon technology, provided by the invention, has the advantages of high production efficiency, high utilization rate of resources and low emission of carbon dioxide.

Aiming at the problem that the acquisition of formaldehyde with low water content decides the feasibility of DMMn synthesis and directly influences the product synthesis conversion rate, aldehyde canbe concentrated to 85 percent through a vacuum concentration system, the water content in the formaldehyde is dewatered to 0.5 to 3 percent in a dewatering tower, methyl alcohol with a low boiling point is condensed with the formaldehyde, the polymerization degree controllability of the formaldehyde in a liquid phase is realized, and a formaldehyde alcoholic solution with a polymerization degree nbeing equal to 3 to 10 is obtained, so that the most suitable reaction raw material-the formaldehyde alcoholic solution with a low water content is found for polymethoxy dimethyl ether synthesis. Theformaldehyde vacuum concentration system is combined with a stripping tower principle, so that the formaldehyde alcoholic solution with the low water content is prepared, the water content in the reaction system is reduced, the product decomposition is avoided, the DMMn synthesis conversation rate is efficiently improved, meanwhile, the risk of polymerization during a high-concentration formaldehyde concentration process is avoided due to the introduction of the formaldehyde, the concentration temperature is reduced, the generation of formic acid is reduced, and an advantageous effect is achieved on separating a follow-up polymethoxy dimethyl ether product.

The invention relates to a dual-tower parallel urea synthesizing device, comprising two urea synthesizing towers. Each urea synthesizing tower is communicated with respective liquid ammonia feed pipe,carbon dioxide feed pipe and nail liquid feed pipe; discharge pipes are respectively arranged at the tops of the two urea synthesizing towers; two discharge pipes are connected together and then communicated with a discharge main pipe; and the size and the specification of the two urea synthesizing towers are same. The dual-tower parallel urea synthesizing device reduces the production strength of the urea synthesizing towers, prolongs the stay time of materials in the synthesizing towers, improves the urea synthesizing conversion rate and the yield capacity, has less investment and quick extension and production, saves labor force and matched facilities, allows to repair synthesizing towers having faults or stop the overhaul of any one synthesizing tower under the condition of not stopping production and has simples operation and flexible adjustment.

The present invention relates to a synthesis method of phosphodiesterase (2-ethylhexyl) ester, including the following steps of mixing the phosphorus oxychloride and the 2-ethylhexyl alcohol at molar ratio of 1: (1.9 -2.0), adding the calcium-magnesium catalyst, stirring, controlling the pressure in -0.02Mpa to -0.03Mpa, the dropping rate of phosphorus oxychloride at 100+/-5kg/h and the temperature at 55+/-5 DEG C, adding the phosphorus oxychloride for continuous reaction for 4 to 5 hours; maintaining the negative pressure above 700mmHg, heating up to 70+/-2 DEG C to continue reacting for 4 to 5 hours to obtain solids; basifying, acidifying to obtain the crude ester; distilling: heat-distilling the crude ester, collecting the fraction of between 170 and 175 DEG C, to obtain the phosphodiesterase (2-ethylhexyl) ester. The preparation method provided by the invention simplifies the synthesis process, with simple method easy to operate, available raw materials and low cost. Moreover, the synthetic conversion rate of phosphodiesterase (2-ethylhexyl) ester obtained by the method is up to 88%, and the product quality is stable with good effect for use, various technical indicators reaching the standard.

The invention relates to a reaction tower for ammonia synthesis. Main components comprise an outer cylinder, a top cover, a tower top flange, a bottom cover, a tower bottom assembly, an inner cylinder, a catalyst basket, a casing pipe mechanism, a heat exchanger, heat exchange pipes, a circulation pipe, a product output pipe and a filter membrane. The upper end of the outer cylinder is connected to the top cover. The upper end of the top cover is connected to the tower top flange. The top cover is provided with a raw material inlet. The lower end of the outer cylinder is connected to the bottom cover. The lower end of the bottom cover is connected to the tower bottom assembly. The outer cylinder wraps the inner cylinder. The upper part of the inner cylinder is provided with the catalyst basket. The casing pipe mechanism is arranged at the lower end of the catalyst basket. The heat exchanger is arranged at the lower end of the inner cylinder. The heat exchanger is provided with the heatexchange pipes spirally and inclinedly distributed, the heat exchanger is provided with a circulation pipe, a product output pipe is arranged at the lower end of the heat exchanger and the filter membrane is arranged in the product output pipe. The reaction tower has the advantages of high ammonia synthesis conversion rate, compact structure, small floor space, neat internal structure, convenientmaintenance, energy saving, high ammonia separation efficiency and high ammonia quality.

The invention discloses a D-phenylglycine methyl ester phosphate crystal, a preparation method and a solution, and the preparation method comprises the following steps: step a, adding Dphenylglycine and methanol into a reaction tank, uniformly stirring, and feeding phosphoric acid; step b, after the phosphoric acid is fed, carrying out reflux reaction; c, after the reflux reaction in the step b isfinished, carrying out vacuum dehydration, and then repeating the following operations for n times: adding methanol, continuously carrying out the reflux reaction, and carrying out vacuum dehydrationafter the reflux reaction is finished; and d, adjusting the pH value to be acidic, adding the Dphenylglycine methyl ester phosphate seed crystal for crystallization, and drying to obtain the Dphenylglycine methyl ester phosphate crystal. The problems of low subsequent enzymatic synthesis conversion rate and severe corrosion to equipment in the related art are solved.

The invention provides a preparation method of hydroxamic acid. The preparation method comprises the following steps: reacting acid anhydride with hydroxylamine under the catalysis of alkali, and acidifying after the reaction is completed, wherein the acid anhydride is C4-C12 cycloalkane fatty acid anhydride or aromatic acid anhydride. According to the preparation method, hydroximation reaction can be realized without heating, the reaction conditions are mild, side reactions are few, the purity of the obtained product is high, and the concentrate product obtained by flotation is high in recovery rate and grade. Secondly, the synthesis conversion rate of the product is high, the raw material consumption ratio is reduced, the synthesis cost is greatly reduced, the alkali consumption in the preparation process of the method is greatly reduced, the acid required in the subsequent acidification process is also reduced, the generated waste residue sodium chloride is reduced and the wastewater discharge amount is reduced by about 50% or above.

The invention relates to a five-sodium tetrathiocarbonate synthetic method. The method uses sodium thiocarbonate and sulphur powder as raw material. Excess sulphur powder is used to synthesize five-sodium tetrathiocarbonate rapidly in high efficiency under the synergetic action of a phase transfer catalyst ionic liquid and microwaves. The ionic liquid can be used as a phase transfer catalyst, a solubilizer and a microwave absorbent; and a subsidiary product of four-sodium tetrathiocarbonate has small amount. The method is simple in operation and easy to separate and realize continuous production. The five-sodium tetrathiocarbonate synthetic method provides a new idea and a new method for the five-sodium tetrathiocarbonate synthesis.

The invention discloses a synthesis process of uridine, and belongs to the technical field of organic synthesis. The process comprises the following steps of uniformly mixing cytidine serving as a main raw material with water, controlling the temperature to be 10-60 DEG C, respectively adding a nitrous acid reagent and inorganic acid or organic acid, carrying out heat preservation reaction for 1-10 hours, ending the reaction after the raw material is added, controlling the pH value to be 1-4 after the reaction is completed, carrying out reduced pressure concentration to obtain a uridine concentrated solution, dropwise adding an alcohol solvent into the uridine concentrated solution, and crystallizing to obtain the product uridine. The process is easy to operate, thorough in reaction and high in reaction speed, and the synthesis period is greatly shortened. In addition, the conversion rate of the process is up to 90% or above, the yield is up to 80% or above, and the purity is greater than 99.5%.

The invention discloses a preparation method of brominated epoxy resin special for a copper-clad plate and a product prepared by using the preparation method. The preparation method comprises the following steps of by adopting bisphenol A liquid epoxy resin and tetrabromobisphenol A as raw materials, adding a catalyst for reaction to obtain intermediate resin; adding the bisphenol A liquid epoxy resin again for polymerization and chain extension to obtain the target brominated epoxy resin. The brominated epoxy resin prepared by using the preparation method provided by the invention has the advantages of high purity, low product chrominance and stable product quality.

The invention relates to the technical field of building admixtures, in particular to a concrete water reducing agent and a preparation method thereof. The concrete water reducing agent comprises a photopolymerizable monomer selected from alkoxy polyethylene glycol esterification intermediates, and a photoinitiator which is benzoin. According to the concrete water reducing agent provided by the invention, the alkoxy polyethylene glycol esterification intermediate is adopted, slump retaining performance and water reducing performance can be both considered, meanwhile, the reaction can be carried out at normal temperature or low temperature, monomer prepolymerization is directly initiated through light irradiation, the polymerization rate is greatly increased, the synthesis conversion rate is increased, and the sensitivity is reduced; and in addition, the sulfonic acid group is added, so that the surfaces of cement particles can be stably adsorbed, the hydration reaction can be effectively delayed, the dispersing and slump retaining effects in concrete with medium and low strength grades are enhanced, and the market application prospect is extremely wide.

The invention discloses a synthesis method of pentaerythritol polyoxyethylene ether stearate. The synthesis method comprises the following steps: 1, heating melting: adding stearic acid, pentaerythritol polyoxyethylene ether and a fixed superacid catalyst to a reaction kettle, and heating melting, the molecular weight of pentaerythritol polyoxyethylene ether being 5000-9000; stirring until the materials in the reaction kettle are completely molten; 2, esterification reaction: continuously carrying out esterification reaction on the material obtained in the step 1 in the reaction kettle until the acid value of the material is less than or equal to 15mg. KOH/g through sampling test; and 3, cooling and filtering: taking out the material obtained in step 2 from the reaction kettle, cooling, and filtering to obtain pentaerythritol polyoxyethylene ether stearate. According to the method, the synthesis conversion rate of pentaerythritol polyoxyethylene ether stearate is effectively increased,and the production requirements of enterprises are met.

The invention discloses a process for synthesizing an organic polymer flocculant. The process comprises the following steps: (a) measuring certain quantities of polyacrylamide, formaldehyde, dimethylamine and hydrochloric acid for later use, wherein in percentage by mass, the hydrochloric acid accounts for 1.0 percent of the total mass; (b) placing the formaldehyde in a reaction container; (c) slowly adding the polyacrylamide and a catalyst into the reaction container and stirring with adding; (d) then placing the reaction container into water bath to heat; (e) next, adding the dimethylamine into the reaction container; (f) cooling and then adding the hydrochloric acid to carry out quaternization; (g) finally, obtaining the target product by carrying out evaporation concentration and filtration. According to the invention, the qualified organic polymer flocculant can be successfully synthesized; the synthesis process is simple; the synthesis conversion rate is high; the process is convenient for workers to operate; synthesis cost of the organic polymer flocculant is greatly reduced; in the synthesizing process, by controlling the concentration of the hydrochloric acid, reaction efficiency and product performance are further improved.