17results about How to "Increased space-time yield" patented technology

The invention belongs to the technical field of biological catalysis, and particularly relates to application of R-transaminase and a mutant thereof in asymmetric synthesis of chiral amine compounds. The amino acid sequence of the R-transaminase is as shown in SEQ ID NO. 1. The amino acid sequences of the R-transaminase mutants are respectively shown as SEQ ID NO: 2 (G66L), 3 (F127A), 4 (F127M), 5 (G66L / F127M), 6 (G66L / F127A), 7 (G66L / F127M / L160I) and 8 (G66L / H67N / F127M / L160I). The recombinant transaminase mutant obtained by the invention has the advantages of high catalytic activity, strict stereoselectivity, mild reaction conditions and the like for various cyclic ketone and N-heterocyclic ketone compounds.

The invention discloses a heterogeneous catalyst for preparing methyl formate through CO esterification and a preparation method and application of the heterogeneous catalyst, and belongs to the field of methyl formate synthesis. The heterogeneous catalyst comprises a palladium active component, an auxiliary agent and a carrier, the auxiliary agent is selected from La and / or Ce; the loading capacity of the palladium active component is 0.01-0.6% of the mass of the carrier; and the loading capacity of the auxiliary agent is 0.01-10% of the mass of the carrier. Compared with a catalyst auxiliary agent reported in the literature, the rare earth auxiliary agent disclosed by the invention can enhance the interaction between the precious metal and the carrier, effectively improve the utilization rate of the precious metal, reduce the dosage of the precious metal and the production cost of the catalyst, and remarkably improve the economical efficiency of the technology. The preparation method disclosed by the invention is simple in process, easy to realize large-scale amplification and excellent in catalyst performance, and can be applied to a production technology for preparing methyl formate through CO esterification.

The invention discloses a device for resource treatment of iron phosphate wastewater through cooperation of a spiral carbon felt and a magnesium metal plate, the device comprises an electrolytic reaction device, the electrolytic reaction device comprises an iron phosphate wastewater container and a spiral device arranged in the iron phosphate wastewater container, and the spiral device comprises a spiral device and a modified carbon felt wound on the spiral device; the modified carbon felt is wound upwards clockwise around the spiral structure of the spiral device from the bottom end of the outer wall of the spiral device, and the modified carbon felt is fixed at equal intervals in the winding direction through a fixator and is wound to the top end of the spiral device; a magnesium metal plate is arranged in an inner hole of the spiral device; the spiral device is provided with a precipitator corresponding to the bottom of the magnesium metal plate; the modified carbon felt is used as the cathode to replace a traditional titanium plate or graphite plate, the waste plastic and the waste carbon felt are made into the spiral device in a spiral shape through the microwave-assisted cracking technology, the modified carbon felt and the spiral device form the spiral device, the design cost is further reduced, struvite is efficiently recycled, and the recycling cost is reduced.

The invention belongs to the field of chemistry and chemical engineering, and particularly relates to a reaction device for preparing isosorbide through two-step dehydration continuous reaction of sorbide. The device comprises a first-stage dehydration reactor and a second-stage dehydration reactor which are communicated, the upper part of the first-stage dehydration reactor is connected with an inlet pipeline, an outlet of the inlet pipeline extends into the bottom of the reactor, and a discharge port of the first-stage dehydration reactor is connected with a feed port of the second-stage dehydration reactor through a downward inclined connecting pipeline; the outlet of the inlet pipeline of the secondary dehydration reactor extends into the bottom of the reactor; partition plates are arranged in the first-stage dehydration reactor and the second-stage dehydration reactor; each of the first-stage dehydration reactor and the second-stage dehydration reactor is provided with a stirring component; each stirring component comprises motors respectively arranged at the upper ends of the first-stage dehydration reactor and the second-stage dehydration reactor, and stirring paddles which are connected with the lower ends of the motors and extend into the inner cavities of the reactors. According to the invention, two-step dehydration for preparing isosorbide from sorbitol can be continuously carried out, the reaction efficiency and the time space yield are improved, and the reaction cost is saved.

The present invention relates to the field of catalyst technology, and discloses a CO2 hydrogenation to olefins catalyst, a preparation method thereof and an application thereof. The active components of the CO2 hydrogenation to olefins catalyst include iron, manganese, sodium and rhenium; in the CO2 hydrogenation to olefins catalyst, the molar amount of manganese is not less than 10% of the molar amount of iron, the proportion of rhenium is 5-8wt‰, and the proportion of sodium is not less than 1wt%. The CO2 hydrogenation to olefins catalyst of the present invention has good catalytic activity, selectivity and anti-carbon deposition ability, can achieve a high olefin space-time yield, and maintain good catalytic stability.

The present invention belongs to the technical field of hydrogen peroxide preparation, and proposes a method for in-situ synthesis of H2O2 based on low-temperature plasma driven hydrogen production. The in-situ synthesis method of H2O2 uses water vapor as a hydrogen source, utilizes plasma to drive the water gas reaction to produce hydrogen, and reacts with oxygen to generate H2O2 in situ, thereby realizing the one-step generation of H2O2 from CO, O2 and water vapor in a plasma reactor. Compared with the anthraquinone method, the reaction conditions of the present invention are mild and the process flow is simple. Compared with the direct generation of H2O2 from hydrogen and oxygen, the present invention effectively avoids the explosion risk caused by the contact between hydrogen and oxygen, and at the same time realizes the resource utilization and high value of CO in industrial waste gas. In addition, the present invention can greatly improve the space-time yield of H2O2, reaching 2700 g H2O2 L ‑1 h ‑1 The above has achieved exponential growth compared to existing technologies and made significant technological progress.

The application belongs to the technical field of 2,5-furan dicarboxylic acid (FDCA) biosynthesis, and particularly relates to an engineered Pseudomonas and application and a method thereof in 2,5-furan dicarboxylic acid biosynthesis. The engineered Pseudomonas takes MB04S-HMF1 as a starting strain, and 7 copies of a glycerolaldehyde-3-phosphate dehydrogenase gene expression cassette and an aldehyde dehydrogenase gene expression cassette are inserted into a 16s rDNA site of a genome of the starting strain, the glycerolaldehyde-3-phosphate dehydrogenase gene expression cassette comprises P MP00 a promoter, a gapA gene and a gapB gene, and the aldehyde dehydrogenase gene expression cassette comprises P MP00 a promoter and an aldehyde dehydrogenase gene. The engineered strain has good growth performance, extremely high substrate conversion rate and space-time yield, completely eliminates byproduct accumulation, has excellent operation stability and multi-batch recycling ability in continuous multiple recycling, and has extremely high genetic and phenotypic stability.

The invention provides a pressurized ammonia decomposition reactor and an ammonia decomposition method, and relates to the field of ammonia decomposition. The reactor body comprises a reactor inner cylinder and a reactor outer cylinder, the reactor outer cylinder is sleeved outside the reactor inner cylinder, and a preheating space is formed between the reactor outer cylinder and the reactor inner cylinder; an electric heating rod is arranged in the reactor inner cylinder, and a wiring end of the electric heating rod penetrates through the reactor inner cylinder and extends out of the reactor body; the reactor inner cylinder is filled with a catalyst; one end of the reactor inner cylinder is provided with a reaction gas inlet extending to the outside of the reactor body, and the other end is provided with a generated gas outlet; a cold ammonia gas inlet communicated with the preheating space is formed in one end of the reactor outer cylinder, a cold ammonia gas outlet communicated with the preheating space is formed in the other end of the reactor outer cylinder, and the cold ammonia gas outlet is connected into the reaction gas inlet. The problem that a traditional ammonia decomposition reactor cannot bear high pressure can be solved, the energy utilization efficiency and the space-time yield are improved, and high-pressure ammonia-hydrogen mixed gas can be effectively produced to meet the requirements of various rear-end application scenes.

The invention provides an L-alanine production strain and a construction method and application thereof.The L-alanine production strain is characterized in that a dns gene, a vnp1 gene and a vnp2 gene in a genome of vibrio natriureticus are sequentially knocked out through gene modification with the vibrio natriureticus as an original strain, a series of key competitive pathway genes pflB, lldh, dldh, pta, ackA and adhE are knocked out in order to block an organic acid fermentation pathway of the vibrio natriureticus, and the vibrio natriureticus is obtained; the production of L-alanine is increased, the accumulation of organic acids is reduced, pXtuf-alaD plasmids are transferred to increase the gene copy number, and by cooperating with the ultrafast growth characteristic of the starting strain vibrio natriureticus, the constructed strain has a clear genetic background, shows efficient transformation ability in the subsequent anaerobic production stage, can efficiently produce L-alanine, and has a wide application prospect. Good industrial application prospects are realized.

The present invention relates to a method for preparing a carbonyl intermediate by electrocatalytic oxidation of a nickel-vanadium nanosheet catalyst. The method adopts a flow-type electrolytic cell for reaction. In the anode chamber, the nickel-vanadium nanosheet catalyst is used as a working electrode, and a reactant alcohol intermediate, a mixed solvent and a nitroxide free radical are added and stirred evenly; in the cathode chamber, a nickel plate is used as a counter electrode, an alkaline solution is used as a cathode liquid, and the anode and cathode liquid storage chambers are pumped into a reactor through a circulation pump to start an electrocatalytic oxidation reaction. After the reaction is completed, the reaction liquid is cooled and then an organic solvent is added for extraction, and the organic layer is distilled under reduced pressure to obtain a carbonyl intermediate compound. The transition metal nickel-vanadium catalyst used in the present invention has low cost, avoids the consumption of rare precious metals, and solves the technical problems of high cost, high environmental pollution, low yield, long production cycle, etc. of the process route for preparing carbonyl intermediate compounds in the current process, and has the advantages of low reaction cost, high yield, short production cycle, high time-space yield, etc.

The invention provides a synthesis method and application of an H-shaped slice high-silicon mordenite molecular sieve, and belongs to the technical field of molecular sieve synthesis and application. The preparation method comprises the following steps: mixing tetraethylammonium hydroxide and long-chain pyrrolidinium salt as template agents with an alkali source, an aluminum source and a seed crystal to form silicon-aluminum sol, aging the silicon-aluminum sol, carrying out a crystallization synthesis reaction, and carrying out ammonium ion exchange, drying and roasting to obtain the H-type high-silicon slice mordenite molecular sieve (MOR). According to the synthesized H-shaped sheet high-silicon mordenite molecular sieve, the Al element is enriched in an eight-membered ring of an MOR zeolite molecular sieve skeleton structure, acid sites which are subjected to side reactions in HMOR can be effectively shielded, and the H-shaped sheet high-silicon mordenite molecular sieve has good catalytic activity and product selectivity when being applied to a reaction for synthesizing methyl acetate through carbonylation.

The invention discloses a system and a method for continuously synthesizing aromatic diisocyanate. The method comprises the following steps: continuously introducing an aromatic diamine solution and hydrogen chloride gas into a salifying kettle for reaction, and carrying out primary and secondary photochemical reactions on a liquid-phase material and phosgene after the salifying reaction to obtain a diisocyanate synthetic solution; the tail gas of the primary and secondary photochemical reactions is condensed by a condenser, the condensate returns to the photochemical kettle for continuous reaction, the uncondensed gas phase enters the absorption tower, the absorption liquid returns to the primary photochemical kettle for reaction, and the unabsorbed part of the gas phase enters the salifying kettle for reaction. The method can realize continuous synthesis of isocyanate, can effectively utilize synthesis tail gas, and reduces hydrogen chloride raw material cost and tail gas treatment cost; the phosgene is utilized to the maximum extent, the phosgene consumption is reduced, the product yield is improved, and the method has the advantages of low consumption of auxiliary raw materials and convenience in industrial implementation.

This invention provides a strain derived from Clostridium difficile (Clostridium difficile) Clostridioides difficile This invention relates to mutants of glutamate dehydrogenase and their applications. The mutants are single-site, two-site, or multi-site mutants of glutamate dehydrogenase. This invention effectively solves the problems of inactivity or low activity of glutamate dehydrogenase in the biocatalytic transformation of 2-carbonyl-4-(hydroxymethylphosphono)butyric acid as a substrate, and provides a continuous chemical method for the synthesis of 2-carbonyl-4-(hydroxymethylphosphono)butyric acid using a microchannel reactor throughout the entire process.

The invention belongs to the technical field of gene engineering, and particularly relates to a nitrile hydratase mutant and application thereof. On the basis of wild type nitrile hydratase from rhodococcus ruber, a mutation site which has a remarkable influence on the activity of the nitrile hydratase is determined by predicting, screening and verifying key active sites, and the nitrile hydratase mutant with improved activity and application of the nitrile hydratase mutant in production of amide compounds are provided. The nitrile hydratase mutant provided by the invention has the advantages that the unit thallus dry weight enzyme activity reaches up to 3649.95 U / g DCW, which is 142.98% higher than that of a wild type; the specific enzyme activity of the purified nitrile hydratase pure enzyme can reach 3589.44 U / mg, and the efficiency of converting nitrile substances into amide products is improved. When the mutant provided by the invention is used for conversion, 2, 6-difluorobenzamide, nicotinamide, cinnamamide, acrylamide and other amide substances can be rapidly produced, and the mutant has higher space-time conversion rate and shorter conversion time.

The invention provides a synthesis method and application of an H-type high-silicon-wafer-shaped MOR zeolite molecular sieve, and belongs to the technical field of synthesis and application of molecular sieves. The method comprises the following steps: adding an aluminum source into a mixed solution containing an alkali source, tetraethylammonium hydroxide, long-chain bipiperidine onium salt and water to form slurry, adding a silicon source and a small-grain MOR zeolite molecular sieve seed crystal into the slurry, uniformly mixing to obtain silicon-aluminum sol, aging the silicon-aluminum sol, carrying out a crystallization synthesis reaction, carrying out ammonium ion exchange on the obtained crystallization product, and drying to obtain the small-grain MOR zeolite molecular sieve. And filtering, washing, drying and roasting to obtain the H-type high-silicon-wafer-shaped MOR zeolite molecular sieve. According to the molecular sieve synthesized by the invention, the Al element is enriched in an eight-membered ring of an MOR zeolite molecular sieve skeleton structure, the quantity of B acid in the eight-membered ring is increased, and the molecular sieve has a small-grain morphology feature structure, can effectively shield acid sites in side reaction in HMOR, is applied to a reaction for synthesizing methyl acetate by carbonylation of dimethyl ether, and has a good application prospect. The catalyst has the advantages of high catalytic activity, good product selectivity, simple preparation process and easy industrial amplification.