85 results about "Catalytic method" patented technology

The invention discloses a catalytic method for converting alpha-olefin in an alkane-olefin mixture into internal olefin and application, raw materials and a solid acid catalyst are carried out in a fixed bed or a reaction kettle, the reaction temperature is 50-150 DEG C, the reaction pressure is 15-400 psi, and the reaction environment is an inert gas atmosphere; when the reaction is carried out on the fixed bed, the mass space velocity of the solid acid catalyst is 1h <-1 >-20h <-1 >; when the reaction is carried out in the reaction kettle, the conversion frequency of the raw materials is 5000 mol substrate mol acid site density <-1 > h <-1 > to 50000 mol substrate mol acid site density <-1 > h <-1 >; wherein the raw material is an alkane-alkene mixture; the solid acid catalyst comprises an active component and a carrier, wherein the carrier contains at least one inorganic oxide; the active component has a structure as shown in a formula (1) and / or a formula (2), in the formula (1) and the formula (2), R is alkyl or phenyl, and n is greater than or equal to 1. According to the catalysis method provided by the invention, the conversion rate of alpha-olefin can be increased, and the proportion of skeleton isomerization products and oligomers in internal olefin products can be reduced.

This invention discloses a solution-based synergistic catalytic method for preparing post-functionalized polyolefins, belonging to the field of polymer material modification technology. The method includes the following preparation steps: adding polyolefin, graft monomer, and catalyst to an organic solvent, stirring until homogeneous, and heating to react, thereby obtaining the post-functionalized polyolefin; wherein the catalyst is a combination of a first catalyst and a second catalyst; and the first catalyst is selected from tert-butyl nitrite, and the second catalyst is selected from N-hydroxysuccinimide and / or N-hydroxyphthalimide. This invention utilizes a synergistic catalytic system composed of tert-butyl nitrite and N-hydroxysuccinimide and / or N-hydroxyphthalimide to activate the C-H bonds of polyolefins in an organic solvent via a free radical mechanism, thereby grafting polar functionalized graft monomers onto the main chain of various polyolefins.

The application discloses a kind of ruthenium grafting manganese aluminum hydrotalcite and catalytic method for C02 hydrogenation preparation formic acid, belong to catalyst technical field, in the application, under the optimized reaction condition, with methanol:water mixture as solvent (5:1), total pressure is 60bar, 60 DEG C, reaction 24 hours, with temperature controller to be heated to the temperature required for reactor.When the temperature inside the reactor reaches the specified temperature, start stirring at a fixed stirring speed (200-800 revolutions / min), after the required reaction time, stop stirring and heating, and allow the reactor to cool to room temperature. The hydrogenation products were analyzed by high performance liquid chromatography, the conversion number (TON) of formic acid reached more than 8000; RuMnAl-LDH was prepared by coprecipitation method, and RuMnAl hydrotalcite catalyst was obtained by heating and activation in a muffle furnace. The preparation process is simple, and the raw materials are easy to obtain. The RuMnAl-LDH catalyst prepared by the application has good catalytic activity and stability in the catalytic hydrogenation of formic acid to formic acid reaction, and has wide application prospect.

The application relates to a method for efficient utilization of solid waste, in particular to a catalytic method for polyolefin waste. The application provides a preparation method of a catalyst for catalyzing polyolefin waste, which comprises the following steps: 1) mixing an acid molecular sieve and an active metal precursor, and roasting to obtain a catalyst precursor; and 2) reducing the catalyst precursor by a reducing agent to obtain the catalyst. In the application, the acid molecular sieve is used as a carrier, solid ion exchange is carried out through high-temperature roasting, the active metal component is solidified in the molecular sieve channel structure, the reduced catalyst has rich acid sites, defect sites and high-dispersed active metals, and in combination with the shape selection and confinement of the molecular sieve structure, efficient conversion of the polyolefin waste into naphtha can be realized.

Production of HFO-1132 and, in particular, HFO-1132E, may be produced from 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113) or CTFE. The present disclosure provides a non-catalytic method for producing trans-1,2-difluoroethylene (HFO-1132(E)), comprising: providing a reactant composition comprising cis-1,2-difluoroethylene (HFO-1132(Z)); and isomerizing the HFO-1132(Z) in an electric heater reactor or a tubular reactor at a temperature of from about 350°C to about 600°C to produce a product composition comprising HFO-1132(E).

This invention provides a 7β-HSDH enzyme mutant, its encoding gene, and its applications. Through artificial mutation screening, 7α-HSDH and 7β-HSDH enzyme mutants with specific amino acid sequences were identified, resulting in improved enzyme activity and catalytic efficiency compared to wild-type 7α-HSDH and wild-type 7β-HSDH. This invention also provides a method for preparing ursodeoxycholic acid using the aforementioned 7α-HSDH and 7β-HSDH enzyme mutants, specifically using NADP... + A one-pot catalytic method for the conversion of chenodeoxycholic acid to ursodeoxycholic acid using NADPH-dependent 7α-HSDH enzyme mutants and NADPH-dependent 7β-HSDH enzyme mutants is employed. This method is simple, yields high product conversion, and can also achieve the conversion of the coenzyme NADP. + / NADPH's self-circulating regeneration eliminates the need for auxiliary enzymes and raw materials used in coenzyme regeneration, greatly reducing production costs and environmental pressure, and possessing enormous potential for industrial applications.

The invention provides a photo-catalytic treatment reactor and a photo-catalytic method for photosensitive dry film developing waste liquid, the reactor comprises: an outer cylinder, an inner cylinder is arranged in the outer cylinder, the outer cylinder and the inner cylinder form an interlayer for storing waste liquid, the outer cylinder is a closed structure, and a liquid inlet pipeline is arranged on the outer cylinder; the inner cylinder is used for introducing the waste liquid in the interlayer in batches, a photocatalyst is arranged on the inner wall of the inner cylinder, an opening and closing door is mounted on the upper end face of the inner cylinder, and a liquid outlet pipeline is arranged on the lower end face of the inner cylinder, penetrates through the lower end face of the outer cylinder downwards and extends out of the outer cylinder; the opening and closing door is rotationally connected with the inner barrel and connected with a driving part on the inner wall of the outer barrel, and when the opening and closing door is closed, the inner barrel can be closed; a stirring part and a light source are arranged on the rotating shaft, the rotating shaft is connected with the output end of the power part, and the rotating shaft downwards penetrates through the upper end face of the outer cylinder from the outside of the outer cylinder and extends into the inner cylinder. The photocatalytic reaction efficiency is improved.

The invention relates to the technical field of flow batteries, and particularly discloses a catalytic system and a catalytic method of a flow battery. The catalytic system comprises an electric pile unit used for realizing conversion between electric energy and chemical energy; the electrolyte storage unit is used for storing electrolyte and comprises a positive electrode electrolyte storage unit and a negative electrode electrolyte storage unit, and functional particles are arranged in the positive electrode electrolyte storage unit and / or the negative electrode electrolyte storage unit; the ultrasonic unit is used for promoting the functional particles to be in contact with the positive electrode electrolyte and / or the negative electrode electrolyte for electrification to generate an electrostatic field; and the circulating unit is used for realizing circulation of the electrolyte between the electrolyte storage unit and the electric pile unit. According to the flow battery catalytic system, the electron transfer process can be optimized, and the problems of slow reaction kinetics and noble metal dependence of the flow battery are solved.

The invention relates to a catalytic method for increasing the content of synthesis gas in biomass carbon dioxide gasification products. The method comprises the following steps: independently dissolving transition metal salt, alkali metal salt or alkaline earth metal salt in water, or jointly dissolving the transition metal salt and at least one of the alkali metal salt or the alkaline earth metal salt in water to form a metal salt solution; biomass powder is added into the metal salt solution for first stirring, a mixed solution obtained after first stirring is subjected to first dipping, first standing and first drying, and a metal-doped autocatalytic biomass raw material is obtained; aluminum oxide powder is added into the metal salt solution for second stirring, the mixed solution subjected to second stirring is subjected to second dipping, second standing, second drying and roasting, and the metal-loaded aluminum oxide catalyst is obtained; and by taking carbon dioxide as a gasifying agent, enabling the autocatalytic biomass raw material and the metal-loaded aluminum oxide catalyst to exist at the same time under the condition of 700-1000 DEG C, and carrying out gasification reaction to obtain a product of which the integral number of synthetic gas is greater than 85%.

The present application relates to a kind of synthetic hydroxytyrosol multi-enzyme catalytic method.The synthetic hydroxytyrosol multi-enzyme catalytic method described in the present application includes first module reaction, second module reaction, third module reaction in turn;The first module reaction is that glycerol is synthesized pyruvic acid by catalysis, wherein the concentration of the glycerol is 1-5mM;The second module reaction is that pyruvic acid is condensed with catechol and ammonium chloride to be L-levodopa by catalysis;Wherein, the concentration of the catechol is 1-5mM, and the concentration of the catechol is greater than the concentration of the glycerol in the first module reaction;The third module reaction is that L-levodopa is synthesized hydroxytyrosol by catalysis.The synthetic hydroxytyrosol multi-enzyme catalytic method described in the present application, reaction 4 hours hydroxytyrosol molar conversion rate can reach 71.5%, compared with one-pot method has obvious advantage, in the same reaction time molar conversion rate is compared with one-pot method and increased nearly 6 times.

The application discloses a catalytic flue gas treatment device and a yellow phosphorus tail gas purification system, and aims to solve the technical problem of reducing the hidden danger of oxygen supplement to the flue gas to be treated during the operation of the catalytic flue gas treatment device. The device comprises a reaction system, a regeneration liquid circulation system and a flue gas conveying system, and further comprises an oxygen supplement system. The oxygen supplement system comprises a second air blower, an airflow adjusting device and an oxygen supplement gas distribution pipe network. The second air blower and the airflow adjusting device are connected with each reactor through the oxygen supplement gas distribution pipe network, so that the airflow generated by the second air blower is adjusted in flow by the airflow adjusting device, and then forms the oxygen supplement gas and enters the flue gas to be treated in the corresponding reactor. The oxygen concentration in the oxygen supplement gas is greater than that in the flue gas to be treated before the mixed oxygen supplement gas. The safety hidden danger possibly caused by the external mixing of the oxygen supplement in the reactor is avoided.

The application relates to an array type magnetic driving continuous flow system and a catalytic method. The array type magnetic driving continuous flow system comprises at least one reactor unit, and the reactor unit comprises: an upper cover plate and a lower cover plate which are oppositely arranged; a reactor main channel which is arranged between the upper cover plate and the lower cover plate; a solid particle fixing cavity which is arranged in the reactor main channel; magnetic nano particles which are arranged in the solid particle fixing cavity; and a magnetic driving array which comprises at least one group of regularly arranged permanent magnets, the group of permanent magnets are respectively fixed on the upper cover plate and / or the lower cover plate, and can generate a magnetic field which acts on the magnetic nano particles, so that the magnetic nano particles are reversibly fixed in the solid particle fixing cavity. The application effectively solves the problems of the magnetic catalyst in the continuous flow system, such as fixing, mass transfer, flux and recovery, and provides a continuous flow catalytic solution which is efficient, flexible and easy to enlarge.

The present invention relates to systems and methods for catalytic removal of oxidized contaminants (for example, nitrite, chromate, chlorate, trichloroethene, CFC-11, 4-nonylphenol, RDX, and perfluorooctanoate) from water and wastewater. In some aspects, the catalytic method of removing oxidized contaminants comprises using precious metal nanoparticles as catalysts to reduce the oxidized contaminants.

The application discloses an interactive catalytic method and platform based on molecular simulation and artificial intelligence, and realizes intelligent design of a catalyst through data classification, condition optimization, structure modeling and mechanism analysis. After being standardized, the catalytic data uploaded by a user is divided into two categories: data set A is used for recommending optimal reaction conditions by a multi-objective optimization algorithm; and the catalyst structure of data set B is optimized by quantum chemistry software to construct a three-dimensional model, and multiple intermediate, transition state structures and geometric / electronic descriptors are optimized. Through feature screening and dimension reduction technology, a double-model collaborative prediction system of model E and model F is constructed, and finally, model F is used to drive a molecular generation algorithm to screen high-performance catalysts. The application can realize flexible adaptation to specific application scenarios, meet the urgent needs of the industry for efficient and accurate catalyst performance prediction and intelligent design, and effectively help the industry to reduce costs and increase efficiency, and accelerate the catalyst research and development process.

This invention discloses a recombinant *E. coli* strain for producing phenyllactic acid, a lactate dehydrogenase mutant, a whole-cell catalytic method for preparing phenyllactic acid, and the application of the aforementioned recombinant *E. coli* strain or lactate dehydrogenase mutant in the catalytic preparation of phenylpyruvic acid from phenyllactic acid. This invention significantly improves catalytic efficiency by modifying the 52nd amino acid of lactate dehydrogenase through site-directed mutagenesis. After mutating glutamine (Q) to valine (V) at position 52 of the *Lactobacillus mucosa* lactate dehydrogenase, the catalytic efficiency is significantly improved even at low cell density (OD). 600 =15) and substrate 15 g / L conditions, almost complete conversion was achieved; and combined with high-density catalysis and surface display optimization, the yield of phenyl lactic acid was increased while the downstream separation and purification costs were significantly reduced, greatly enhancing the potential for industrial production.

The utility model discloses a combined corrosive liquid storage device and catalytic flue gas desulfurization device, solve the technical problem of the heavy structure of regenerative liquid tank, high construction cost, long period and insufficient corrosion resistance. Including: prefabricated storage tank, prefabricated storage tank main part is made of corrosion -resistant thermoplastic polymer and is distributed to install the sleeve pipe made of corrosion -resistant thermoplastic polymer, and the both ends of each sleeve pipe are installed on the opposite two side walls of prefabricated storage tank and are sealed connection lead -through with corresponding pair of side wall opening respectively, and support structure contains the outer frame of installation in prefabricated storage tank and is used to accommodate and support prefabricated storage tank and the pull rod of distribution installation in outer frame, and each pull rod is correspondingly worn in the corresponding sleeve pipe and is drawn to tie up the opposite two side walls on outer frame respectively. Realized the factory prefabricated production, reduced the field construction workload and period greatly, reduced the civil engineering investment, ensured the long -term safety and reliability of corrosive liquid storage.

The invention discloses a full-automatic photocatalytic reaction platform and a catalytic method thereof, and relates to the technical field of photocatalytic reaction. Comprising an outer box body and an ice maker, the ice maker is connected with the interior of the outer box body through a water pipe, a reaction chamber table is arranged at the top of the outer box body, a fixed protective cover is movably arranged at the top of the reaction chamber table, and an axial flow fan is arranged on the inner side of the fixed protective cover. According to the full-automatic photocatalytic reaction platform, the five groups of xenon lamp assemblies which are circumferentially and equidistantly distributed are adopted as light sources, light can be accurately refracted to the quartz test tube in cooperation with the refracting prism, and it is ensured that a sufficient and directional light source is obtained through photocatalytic reaction; the reflector assembly on the outer side of the xenon lamp holder further improves the light utilization rate. Meanwhile, an optical power meter probe arranged in the outer box body can detect the intensity of refracted light in real time, accurate illumination data support is provided for the test, and the consistency of illumination conditions of different batches of tests is guaranteed.

This invention discloses a method for the efficient catalytic hydrogenation of levulinic acid and its esters to prepare γ-valerol under mild conditions. The method uses water as the reaction solvent and a Ni3P / SBA-15 catalyst to catalyze the hydrogenation of levulinic acid and its esters in a high-pressure reactor or fixed-bed reactor under low-temperature conditions to selectively prepare γ-valerol. The Ni3P / SBA-15 catalyst is obtained by impregnating a Ni3P precursor onto SBA-15 and then reducing it in a hydrogen atmosphere. This invention offers a simple preparation method, readily available raw materials, low cost, and an environmentally friendly, pollution-free reaction process. Furthermore, the catalytic system is relatively simple, with high conversion rates of the reactants, and the γ-valerol yield can reach 100%. After 50 hours of reaction in a fixed-bed reactor, the yield of γ-valerol remains stable, indicating good catalyst stability. This method saves resources, reduces costs, and has promising prospects for industrial application.

This invention belongs to the field of composite materials and wastewater treatment technology, and discloses a method for preparing a dual-effect catalytic membrane through swelling-induced retention and immobilization, and its application. The method first prepares a dual-effect catalyst, then uses organic reagents to induce membrane swelling, enlarging the membrane pores and fixing the dual-effect catalyst. Subsequently, the membrane is naturally dried overnight, achieving adhesive-free assembly and fixation of the membrane and catalyst. This invention can be applied to the removal of tetracycline from water through persulfate advanced oxidation and photocatalytic oxidation. This invention has advantages such as simple preparation process, inexpensive and readily available raw materials, easy separation and recovery of the product membrane, and green and efficient operation. The tetracycline degradation rate reaches 98.09% in 60 minutes using persulfate advanced oxidation technology, with up to 5 recycling cycles. Furthermore, within 60 minutes, photocatalytic oxidation of tetracycline degrades it to 82.60%. This solves the problems of difficult recovery, high risk of secondary pollution, and inability to remove organic pollutants using multiple catalytic methods associated with traditional powdered catalysts, providing broad industrial application prospects for the treatment of tetracycline-containing wastewater.

The invention discloses a method for preparing acetone through photo-thermal catalytic methane conversion, and belongs to the field of methane conversion. The method comprises the following steps: adding a catalyst, water and reaction gas containing methane gas into a reactor, wherein the catalyst is formed by loading an active metal component on a nano semiconductor carrier; and reacting under the coupling condition of illumination and heating at 25-150 DEG C to generate a liquid product containing acetone. The catalyst is prepared by loading transition metal and noble metal on a nano semiconductor material. The metal-loaded nano-particles of the photocatalyst prepared by the method are relatively small in particle size and good in dispersity, and the photocatalyst has relatively strong ultraviolet-visible light absorption capability and is beneficial to activation of methane. Under the illumination of ultraviolet-visible light at 25-150 DEG C, the catalyst can efficiently and highly selectively catalyze methane and water to directly react to generate acetone, and meanwhile, excessive oxidation of a product is remarkably avoided. The prepared catalyst has the characteristics of high catalytic activity, good stability, simple process, low cost and the like.

This invention relates to a catalyst for preparing ortho-methylated products of phenol. The catalyst is a composite oxide containing indium oxide, with the composition In₂O₃ / X, where X is a promoter. The promoter is selected from one or more of ZrO₂, HfO₂, ZnO, Cr₂O₃, CeO₂, and MgO, and the amount of the promoter metal is 0.01 to 100 times the molar amount of indium. This invention also discloses the application of this catalyst in the reaction of carbon dioxide hydrogenation coupled with phenol methylation to prepare o-cresol and 2,6-dimethylphenol. Compared with traditional catalytic methods, the catalyst of this invention has low energy consumption, long service life, and can highly selectively convert phenol to o-cresol and 2,6-dimethylphenol with almost no byproduct formation.

The application discloses a catalyst for synthesizing ammonia by using plasma and a preparation method and application thereof, relates to the technical field of synthesizing ammonia by using plasma, and provides a preparation method for preparing copper oxide loaded oxygen-rich vacancy cerium dioxide, wherein the whole preparation process is simple in process and convenient in condition control, and is beneficial to industrial preparation. Moreover, the prepared copper oxide loaded oxygen-rich vacancy cerium dioxide can be used for synthesizing ammonia by using nitrogen and hydrogen as raw materials under the cooperation of plasma under mild conditions of low temperature and normal pressure, the preparation process of the ammonia is simple, high ammonia yield and energy efficiency can be realized under lower power, a new catalyst and a catalytic method are provided for a green ammonia synthesis industry, and the application has a wide market application prospect.

The invention discloses a synthetic method for preparing 1-isobutyryl-2-pyrrolidone through green catalysis, and belongs to the technical field of chemical synthesis. The synthesis method comprises the following synthesis steps: replacing a reactor with nitrogen for three times, filling nitrogen and sealing; the preparation method comprises the following steps: under the protection of nitrogen, dissolving 5.0 mmol of pyrrolidone, 2.75 mmol of isobutyric anhydride and a functional catalyst in 10mL of tetrahydrofuran; cooling to 0 DEG C in an ice bath, slowly dropwise adding triethylamine, and maintaining the system temperature lt; raising the temperature to 25 DEG C from 5 DEG C, reacting for 6 hours, and monitoring the reaction process through TLC; adding 5mL of 1M HCl for quenching, extracting with ethyl acetate for three times (20mL each time), combining an organic phase S5, washing the organic phase with NaHCO, and drying with MgSO; adjusting a water phase with quick lime, standing for layering, and discharging lower-layer water to obtain water-containing triethylamine; and S7, carrying out suction filtration on the organic phase, carrying out rotary evaporation to remove the solvent, and carrying out silica gel column chromatography separation on the residue. According to the method, a DMAP + CuI dual-catalyst system is adopted, so that the diacylation by-products are remarkably reduced, and the yield is increased by 10% or above and is not lower than 97%.

This invention provides the application of a directed mutant glycosyltransferase in the synthesis of galactoside anthocyanins, belonging to the field of enzyme engineering technology. This invention provides a glycosyltransferase mutant, wherein the mutant includes mutations at at least one of the following sites in the amino acid sequence of the glycosyltransferase Vc3GT: position 82, position 139, and position 322. The embodiments of this invention verify the synthesis and catalytic efficiency of the mutants, showing that each mutant can be ligated into an expression vector and, through genetic transformation, a recombinant expression host capable of producing the corresponding mutant protein can be obtained. Furthermore, the recombinant protein obtained after induced expression possesses in vitro enzymatic catalytic activity, and can use malvidin and UDP-galactoside as substrates to catalyze the synthesis of malvidin-3-O-galactoside. The catalytic method is simple, the process cost is low, and it is suitable for large-scale industrial production.

This invention belongs to the field of fine organic synthesis, specifically relating to an electrochemically catalytic method for the direct amination of aromatic hydrocarbon carbon-hydrogen bonds. This invention efficiently converts primary or secondary aromatic hydrocarbons into corresponding amination products in a single reaction. Compared with commonly used methods, this method has significant advantages: (1) it uses widely available and inexpensive primary or secondary aromatic hydrocarbons as starting materials; (2) it requires no metal catalysts, no exogenous oxidants or bases, and uses electrons as a clean oxidation medium, eliminating the need for traditional exogenous oxidants, reducing costs and environmental pollution; (3) it achieves the activation of inert carbon-hydrogen bonds under mild reaction conditions; (4) the reaction uses sulfonylimide substrates as nitrogen sources to introduce amino groups, enabling the target product to be obtained with relatively ideal separation yields and rich product structures.

The invention belongs to the technical field of two-dimensional material preparation, and particularly relates to a method for directly synthesizing an Nb < x > Ta < 2-x > S2C material through a catalytic method. According to the method, niobium powder, tantalum powder, sulfur powder and carbon powder are used as raw materials and sealed in an ampoule bottle to isolate air, and a halogen compound or a halogen simple substance is used as a catalyst to directly synthesize NbxTa (2-x) S2C at high temperature. According to the method, Nb < x > Ta < 2-x > S2C is directly synthesized by heating in an ampoule bottle without air, so that the process flow is simplified, the preparation temperature is reduced, the reaction time is shortened, the use of organic solvents such as acetonitrile is avoided, and the material preparation cost is reduced. Therefore, the method belongs to the Nb < x > Ta < 2-x > S2C preparation method which is low in cost, simple in process, safer and more reliable, and can be widely applied to the fields of energy storage batteries, electromagnetic interference shielding, catalysis and plasma metamaterials.

This invention provides a 7α-HSDH enzyme mutant and a 7β-HSDH enzyme mutant, their encoding genes, and their applications. Through artificial mutation screening, 7α-HSDH and 7β-HSDH enzyme mutants with specific amino acid sequences were identified, resulting in improved enzyme activity and catalytic efficiency compared to wild-type 7α-HSDH and wild-type 7β-HSDH. This invention also provides a method for preparing ursodeoxycholic acid using the aforementioned 7α-HSDH and 7β-HSDH enzyme mutants, specifically using NADP... + A one-pot catalytic method for the conversion of chenodeoxycholic acid to ursodeoxycholic acid using NADPH-dependent 7α-HSDH enzyme mutants and NADPH-dependent 7β-HSDH enzyme mutants is employed. This method is simple, yields high product conversion, and can also achieve the conversion of the coenzyme NADP. + / NADPH's self-circulating regeneration eliminates the need for auxiliary enzymes and raw materials used in coenzyme regeneration, greatly reducing production costs and environmental pressure, and possessing enormous potential for industrial applications.

The application discloses a catalytic method for synthesizing furan alkenyl-cycloketone compounds, a catalyst and a preparation method thereof, relates to the technical field of chemical catalysis and organic synthesis, and the catalyst is a solid catalyst with variable mesopore diameters and containing acid-base double sites; the catalyst is composed of an acidic mesoporous carrier and basic metal hydroxide loaded on the carrier; the acidic mesoporous carrier is a composite of SiO2 and acidic metal oxides, and is prepared by hydrolysis and calcination of soluble precursors of acidic metals, tetraethyl orthosilicate and hydroxyl carboxylic acid pore-forming agents. The mesopore diameter of the catalyst is 3.41nm-11.2nm, the specific surface area is 172.4-869.6m 2 / g, the acid content is 0.180-0.973mmol / g, the base content is 0.016-0.125mmol / g, and the catalyst has the characteristics of recyclability, high temperature resistance, solution non-pollution and the like.

The application provides an enzymatic preparation method of histamine dihydrochloride, and belongs to the technical field of biochemistry. The method uses L-histidine as a substrate, uses a histidine decarboxylase mutant as a biological catalyst, and converts the substrate into histamine under suitable enzyme catalytic reaction conditions. Finally, the histamine dihydrochloride is obtained through a proper extraction and purification process. The substrate conversion rate of the enzyme catalytic reaction is more than 99%, and the purity of the product after extraction is greater than 98%. The enzyme catalytic method has the advantages of high conversion rate, short conversion time, easy extraction and purification, and great industrialization prospect. The method has the advantages of high conversion rate and high yield, and the obtained product has market competitive advantage.

This invention relates to the field of gas catalysis technology, specifically to a gas catalysis system and method for use in industrial boilers. It includes a gas pipe body and a catalyst pipe body disposed on the gas pipe body, the gas pipe body and the catalyst pipe body being in communication. A catalytic assembly is disposed within the gas pipe body, the catalytic assembly including a baffle plate installed within the gas pipe body. One side of the baffle plate has a gas-gathering component for catalyzing the gas, and the other side has an exhaust component for discharging the catalyzed gas. This invention uses a baffle to close the baffle plate, forming a mixing chamber between the baffle plate, the baffle plate, and the pusher plate. The gas is mixed in the mixing chamber by the catalyst. When the baffle plate is opened, the catalyzed gas is discharged through the baffle plate for use.