3869 results about "Catalytic efficiency" patented technology

The invention discloses a high-activity catalyst which catalyzing and activating carbon dioxide to perform the copolymerization reaction with alkylene oxide to synthesize polycarbonate. The catalyst is characterized in that the catalyst is a tetradentate schiff base complex contains one or two organic base groups and has single active site initiation and controllable polymerization. The catalyst has the advantages that under milder conditions and at lower concentration of the catalyst, the catalyst can highly and efficiently catalyze the carbon dioxide to make the copolymerization reaction with the alkylene oxide to prepare the polycarbonate, the catalytic efficiency is 10<6>g polymer/mol catalyst, the polymer molecular weight is adjusted in the range of between 5,000 and 500,000, the molecular weight distribution is less than 2, the alternating structure is over 97 percent, and the catalyst can be degraded into small molecule compounds under certain condition. By utilizing the catalyst, the telomerization reaction between the carbon dioxide and two or more than two types of alkylene oxide can be catalyzed to synthesize a polycarbonate telomer with adjusting glass transition temperature.

Application of spinel ferrite catalyst and a method for urging persulfate to generate free radicals to catalytically degrade organic matters relate to application of spinel ferrite catalyst and a method for degrading organic matters. The invention aims to solve the problems of high probabilities of oxygenolysis and breakage, low strength, impurity dissolution, low catalytic efficiency and difficulty in recovering in the existing catalyst as catalyst generated by sulfate free radicals and complex reaction system, rigor reaction conditions and higher cost in the existing activating technology. The spinel ferrite catalyst, as catalyst for urging the generation of persulfate free radicals, for urging persulfate or mono-persulfate to generate free radicals is applied; and the method comprises the following steps: the spinel ferrite catalyst is adopted as catalyst for urging the generation of persulfate free radicals to urge persulfate or mono-persulfate to generate free radicals; and then sulfuric acid free radicals are used for degrading the organic matters. The application and the method are mainly applied in catalytic degradation of the organic matters.

The invention provides a porous-carbon nano-fiber supported nano-grain catalyst and a preparation method thereof. A porous polyacrylonitrile-based carbon nano-fiber supported nano-grain catalyst is prepared by adopting an electrostatic spinning process, constant-tension hot stretching, preoxidation and chemical activation at a temperature between 500 and 1,000 DEG C. Porous-carbon nano-fiber has the diameter between 100 and 500 nanometers, the aperture between 1 and 500 nanometers, the porosity between 0.1 and 1.0 cm<3>/g and the specific surface area between 100 and 2,000 m<2>/g, and catalyst particles supported on the surface of the nano-fiber has the aperture between 1 and 100 nanometers and the weight percentage content between 1 and 40 percent. The preparation method has the advantage of simple process, and can prepare the porous-carbon nano-fiber supported nano-grain catalyst with high porosity, large specific surface area, strong adsorption activity and catalytic efficiency through the chemical activation at a low temperature.

The invention discloses a catalyst for oxidation and decomposition of organic pollutants in water with ozone and a method thereof for catalyzing sewage treatment with ozone, and relates to a catalyst for decomposing the organic pollutants in water and the method thereof for sewage treatment. By adopting the catalyst, the problems that the traditional solid catalyst for catalyzing the decomposition of organic pollutants in the water with ozone is easy to be oxidized and decomposed by ozone, easy to break, can dissolve out impurities, has low strength and low catalytic efficiency and is difficult to recover can be solved. The catalyst for oxidation and decomposition of the organic pollutants in the water with ozone refers to spinel ferrite or a composite of spinel ferrite; and the method of the catalyst for catalyzing the sewage treatment with ozone comprises the following steps of: adjusting pH and temperature of sewage, then introducing ozone, further adding the catalyst and treating for 1 minute-120 minutes, then using a magnetic field to recover the catalyst, and finally absorbing tail gas of the ozone. The catalyst can improve the removal rate of organic matters to 90%-100%, and can be used for sewage treatment or deep treatment of drinking water.

The invention discloses a low temperature denitration catalytic addictive and a preparation method thereof, and belongs to the field of low temperature denitration catalyst. According to the low temperature denitration catalytic addictive, TiO2-SiO2 is taken as carrier, manganese oxide (MnOx) is taken as active substance, and cerium oxide (CeO2), nickel oxide (NiO) and iron oxide (FeOx) are taken as auxiliary agents. The preparation method comprises following steps: TiO2-SiO2 composite carrier is prepared by sol-gel method; loading of CeO2, NiO or FeOx is realized by one-step dipping; and then the low temperature denitration catalytic addictive is obtained by calcination. The low temperature denitration catalytic addictive possesses high low-temperature denitration catalytic efficiency, wide active temperature window, and relatively high alkali metal poisoning resistance. TiO2-SiO2 is low in cost, and specific area of TiO2-SiO2 is larger than that of pure TiO2 carrier, so that it is beneficial for dispersion of active substances on the surface of TiO2-SiO2, and stability of the active substances. Auxiliary agent NiO or FeOx are capable of increasing low-temperature activity and alkali metal poisoning resistance of the low temperature denitration catalytic addictive, so that the low temperature denitration catalytic addictive is suitable for denitration in dedusted cement kiln at low temperature or even under conditions with unstable temperature.

The invention discloses a preparation method for an iron-nitrogen co-doped porous carbon sphere material. The preparation method comprises the following steps: by taking 2-aminopyridine as a monomer and taking ammonium persulfate and ferric chloride as oxidants, performing in-situ polymerization reaction in a duct of a porous silicon dioxide template to obtain a precursor; performing high-temperature carbonization treatment on the precursor in a tubular furnace and an inert gas nitrogen-gas environment; and removing the silicon dioxide template by hydrofluoric acid to obtain the iron-nitrogen co-doped porous carbon sphere material which is taken as an electric catalyst to achieve good catalytic effect in oxygen gas reduction reaction. The preparation method has the advantages that the process is simple and easy to perform and the raw materials are cheap. The prepared carbon material contains a three-dimensional communicated pore structure, has a high specific surface area and a large pore volume, can effectively improve the electric catalytic activity through the heteroatom nitrogen-iron doping, has relatively high electric catalytic efficiency while being applied as a low-price electric catalyst, and has an important value and significance in the fields of doped type porous carbon material preparation and proton membrane fuel battery electric catalysis.

The invention pertains to chemical engineering field, in particular to a preparation method of a Ru-based catalyst, the catalyst has uniform load and high catalytic efficiency and is used for preparing cyclohexene from benzene through selectively hydrogenation reaction. A precursor of the catalyst is prepared through a cyclohexene/ water component solvent system, and then reduced by a mixing gas of H2 or Ar to prepare the catalyst, and the catalyst consists of ruthenium, a dressing agent and a mesoporous silicon dioxide carrier L, amongst which the active component is ruthenium metal, the dressing agent is a metal oxide, and the precursor is selected from the nitrate or chloride of metal elements in IIA main group, VIII group and IVA main group in the element periodic table; ruthenium and the dressing agent are uniformly carried on the carrier L through the preparation method of the invention. When being used in preparing cyclohexene from benzene through selectively hydrogenation reaction, and compared with the catalyst used for the selectively hydrogenation of industrial benzene, the catalyst has the advantages that: lower the ruthenium consumption, higher selectively hydrogenation activity and selectivity for benzene.

The invention relates to a ZIF-8 material-based hydrogenation catalyst and a synthetic method thereof. The synthetic method particularly comprises the following steps: (1) dissolving zinc nitrate, 2-methylimidazole and a surface active agent with methanol, carrying out stirring reaction for 1-6h at 20-60 DEG C, and standing for 10-18h to obtain a turbid solution; (2) carrying out centrifugal treatment on the turbid solution, placing sediments in a drying oven to be dried to obtain a ZIF-8 carrier after washing with methanol; and (3) dissolving transition metal salt with water, dipping the ZIF-8 carrier into the dissolved transition metal salt, and roasting in a muffle furnace to obtain the ZIF-8 material based hydrogenation catalyst. The hydrogenation catalyst can be used for preparing biodiesel; the biodiesel preparation method comprises the steps of placing the ZIF-8 material based hydrogenation catalyst into a fixed bed reactor to be reduced, and introducing vegetable oil into the reactor for hydrocracking reaction at 300-400 DEG C under the conditions that the hydrogen partial pressure is 2-4MPa, the air speed is 0.9-3.6h<-1> so as to obtain the biodiesel finally. The catalytic efficiency of the synthesized ZIF-8 material based hydrogenation catalyst is improved by dozens of times compared with the catalytic efficiency of a traditional aluminum oxide catalyst.

The invention relates to a nano particle taking Fe3O4 as core, in particular to a TiO2/SiO2/Fe3O4 nano particle with nuclear structure and manufacturing method thereof. The invention solves the technical problems that nano TiO2 particle catalyst has low catalytic efficiency under natural light and is difficult to meet recovery control while remaining high catalyst activity in sewage treatment. The method includes steps of preparing SiO2/Fe3O4 solution, preparing titanium sol and mixing the prepared SiO2/Fe3O4 solution and the titanium sol. The invention adopts ferromagnetic particle as a carrier core and prepared TiO2/SiO2/Fe3O4 particle with nuclear shell structure as catalyst, and the catalyst particle has good dispersity and water-solubility and can be fully contacted with organic pollutant in sewage, thereby not only having high efficiency of suspended phase photocatalyst but also realizing magnetic control of catalyst by super paramagnetic nuclear energy, thus being effectively recovered.

The invention discloses a preparation method of nanometer zinc oxide which takes shell powder as a carrier, and in particular relates to a reproducible porous nanometer zinc oxide powder which takes the shell powder as the carrier and the preparation method thereof. In the preparation method, zinc oxide is loaded by impregnation on the shell powder carrier; firstly, zinc salt solution with appropriate concentration is prepared, and then an activated shell powder carrier is impregnated in the zinc salt solution by certain proportion, and then the obtained solution is stirred and stayed for a certain time, and treated by low temperature and abstersion pretreatment and finally roasted at high temperature, so the nanometer zinc oxide forms high-strength bond with the shell powder and promotes the catalytic activity of the nanometer zinc oxide at the same time. Impregnation can be conducted for a plurality of times to increase load. The nanometer ZnO is characterized by small particle size, good compatibility with materials, high catalytic efficiency, good stability, good regenerability, and the like, and can be applied to the fields of plastics, rubbers, fibers, coatings, home appliances, paints, ceramics, water and environment treatment, pharmaceutical and hygienic articles, etc. In terms of sources of raw materials and production technology, the preparation method not only reduces the production cost of nanometer ZnO catalyst but also is helpful for disposal of the increasingly serious environmental problems, thus bearing great environmental protection significance.

The invention discloses a Cu2O-TiO2/g-C3N4 ternary complex and a preparation and application method thereof. The preparation method comprises the steps that firstly, urea and TiO2 are mixed through a simple physical method, water is added to the mixture, the mixture is dried by distillation, calcination is conducted, and then a binary complex of TiO2/g-C3N4 is obtained; secondly, by means of sediment and reduction processes, the Cu2O-TiO2/g-C3N4 ternary complex is prepared. The preparation method is simple, cost is low, and industrial production is facilitated. The prepared ternary complex serves as a visible-light-driven photocatalyst which has high catalytic activity in the visible region, the catalytic efficiency is high, and various organic pollutants in a solution can be degraded instantly; the prepared ternary complex can also serve as a visible-light-driven photocatalyst which is applied to hydrogen preparing of photocatalytic water splitting, degrading of volatile organic pollutants in air and the like, and very good application prospects are achieved.

The invention relates to a preparation method of a titanium dioxide/graphene composite photocatalyst. The invention is to solve the technical problems that titanium dioxide in a titanium dioxide/graphene compound prepared by the traditional method has a large particle size and low photocatalytic efficiency. The preparation method comprises the following steps that: tetrabutyl titanate is added to a graphene oxide dispersion solution, a concentrated acid is added to adjust the acidity after ultrasonic dispersion, and then deionized water is added to continue to carry out ultrasonic treatment to obtain sol; and then the sol is transferred to a hydrothermal reaction kettle to be subjected to hydrothermal reaction, and then is washed and dried to obtain the titanium dioxide/graphene composite photocatalyst. The particle size of the titanium dioxide in the composite photocatalyst provided by the invention is 5 to 10nm, and the composite photocatalyst can be used for visible light catalytic degradation of methyl orange, and the catalytic efficiency can reach 75% within 2 hours. The titanium dioxide/graphene composite material provided by the invention can be used as a photocatalytic material, a solar cell material and a lithium ion battery cathode material.

The invention discloses an anatase type titanium dioxide nano-fiber photocatalyst and a preparation method thereof, and belongs to the technical field of nano materials and photocatalysts. By the method, a composite nano-fiber is prepared by an electrostatic spinning technology, and then is calcinated in the air to obtain the titanium dioxide nano-fiber photocatalyst, but a sol-gel technology is not used in the process, so that process parameters are easy to adjust and control, multiple factors which influence the final crystallization degree, crystal form, granular distribution and size of a titanium dioxide nano-fiber are eliminated, and a catalytic efficient photocatalysis material can be easily obtained. The titanium dioxide nano-fiber prepared by the method has a large specific surface area, so that visible light is high in catalytic efficiency. The preparation method has a simple process and is easy to adjust and control, and the production cost is reduced. The photocatalyst can be used as a novel photocatalysis material, is high in photocatalysis efficiency under the action of the visible light and meets the requirement and the development direction of a new generation of photocatalysis materials.

The invention discloses a catalyst for converting alcohols and ethers into aromatic hydrocarbons, as well as a preparation method and a use method of the catalyst, and belongs to the technical field of chemical engineering. The preparation method comprises the steps as follows: at first, taking a template agent, kaolin, sodium hydroxide and water as raw materials for preparing a hydrogen type nanoscale ZSM-5 molecular sieve, and then directly preparing the catalyst; or based on the hydrogen type nanoscale ZSM-5 molecular sieve, preparing the two-component, three-component or four-component catalyst with metal and/or a structure enhancer and/or a stabilizing additive. The catalyst comprises the following components in percentage by mass: 30-100% of the needle-like nanoscale ZSM-5 molecular sieve, 0-10% of the metal, 0-50% of the structure enhancer and 0-10% of the stabilizing additive. The invention further provides a method for enabling the catalyst to be used for converting alcohols and ethers into aromatic hydrocarbons. The catalyst is small in particle size, high in catalytic efficiency and low in use cost; the preparation method is simple and efficient; and the use method is reasonable and efficient.

The invention aims at providing a method for synthesizing a scale-shaped graphite-phase nitrogen carbide nanosheet/cobaltosic oxide nanosheet composite material and belongs to the technical field of material preparation and catalysis. The composite material is prepared from the raw materials of functionalized graphite-phase nitrogen carbide and cobalt salt through a hydrothermal method at high temperature. The prepared scale-shaped two-dimensional nitrogen carbide nanosheet/cobaltosic oxide nanosheet composite material is in morphology that a scale-shaped cobaltosic oxide nanosheet nanocomposite material evenly grows on the surface of a two-dimensional nitrogen carbide nanosheet. Compared with a traditional pure two-dimensional nitrogen carbide nanomaterial, the specific surface area of the material and the screening capacity of the material to a catalytic substrate are effectively improved, and the material has more efficient photocatalytic performance. The preparation method has the advantages of simple technology, low cost and high catalytic efficiency; the prepared material has efficient carbon dioxide reducing capacity, and thus has good application prospect in the photocatalysis field of environmental modification, greenhouse gas elimination and the like.

The invention discloses a methyl methoxyacetate preparation method by gaseous carbonylation. The method comprises the step of reacting methylal and a CO-containing gas phase medium under the action of heteropolyacid and supported heteropolyacid catalyst to generate the methyl methoxyacetate, wherein the reaction temperature is 50-300 DEG C and the reaction pressure is 0.1-4MPa. Compared with the traditional ethylene glycol precursor preparation method by liquid phase carbonylation reaction synthesis, the method provided by the invention has the advantages of mild reaction conditions and high catalytic efficiency. Furthermore, the product is easily separated from the catalyst as no solvent is used in the reaction, which is conductive to large-scale industrial production.

The invention belongs to the field of photocatalyst application of organic semiconductors and in particular relates to application of a heteroatom-containing triazine covalent organic framework material in photocatalysis. The heteroatom-containing triazine covalent organic framework material serves as a photocatalyst. The preparation method comprises the following steps: introducing heteroatoms through heterocyclic aldehyde group monomers, carrying out a condensation polymerization reaction with binary or poly-element amidino compounds in the presence of a basic catalyst, thereby obtaining theproduct. The material serves as the photocatalyst, and is capable of degrading organic pollutants in water and producing hydrogen under light conditions by virtue of water splitting. According to themethods, the heteroatom-containing triazine covalent organic framework material is introduced to serve as the photocatalyst, and is high in catalytic efficiency, high in applicability and suitable for large-scale application.

The invention provides a nanometer manganese catalyst for room-temperature catalytic oxidation of formaldehyde and a preparation method thereof. The nanometer manganese catalyst comprises an oxide carrier and an active component MnO2 which is loaded on the oxide carrier. The oxide carrier accounts for 0-85 % of mass of the nanometer manganese catalyst; the active component MnO2 accounts for 15-100% of mass of the nanometer manganese catalyst; and a surfactant accounts for 0-15% of mass of the nanometer manganese catalyst. By the use of the catalyst, formaldehyde can be completely oxidized intocarbon dioxide and water under the condition of room temperature. The catalyst has high catalytic efficiency, good stability and long service life. After 120 h of the reaction, formaldehyde removal rate is still maintained at 82% and above, and there is no secondary pollution. There is no need to provide light source, heat source, complex equipment and external conditions. The preparation methodis low-cost, has a simple and feasible production process, and has a wide application prospect.

The synthesis method of methyl ethyl carbonate belongs to the technical field of organic compounds synthesized by ester exchange. Dimethyl carbonate and diethyl carbonate, or dimethyl carbonate and ethanol are used as raw materials to perform ester exchange in the presence of catalyst. The reaction mode comprises two kinds of fixed bed continuous reaction and kettle-type reaction. The catalyst issolid alkali catalyst in which the carrier is active carbon, carbon molecular sieve or mesoporous carbon and the active component is Na2O, K2O, MgO, CaO, SrO or BaO. In the process of fixed bed continuous synthesis, the catalyst is stable without inactivation after long-term use, thereby retaining the high yield of the methyl ethyl carbonate, simplifying the production process, and achieving environmental friendliness and energy conservation. In the kettle-type reaction, the catalytic efficiency is high, the catalyst can be recovered by simple filtering and re-sintering, and the target product can be obtained in short time with high yield.

The invention discloses a preparation method for a three-dimensional molybdenum disulfide nanoflower-graphene composite material and application of the three-dimensional molybdenum disulfide nanoflower-graphene composite material as an electrochemical hydrogen evolution catalyst. According to the invention, the three-dimensional molybdenum disulfide nanoflower-graphene composite material is prepared through a one-step hydrothermal method; and the obtained composite material is used to modify a glassy carbon electrode after ultrasonic dispersion so as to obtain a three-dimensional molybdenum disulfide nanoflower-graphene composite material modified electrode. The three-dimensional molybdenum disulfide nanoflower-graphene composite material is mainly applied to electrochemical hydrogen evolution; and a linear scanning curve (polarization curve) is used to detect the catalytic activity of the synthesized molybdenum disulfide nanoflower-graphene composite material, and a cyclic voltammetry curve is employed for testing the stability of the molybdenum disulfide nanoflower-graphene composite material. According to the invention, synergism of molybdenum disulfide nanoflower and graphene in the three-dimensional molybdenum disulfide nanoflower-graphene composite material is made full use of to improve the catalytic efficiency of electrochemical hydrogen evolution and to effectively enhance the stability of the catalyst so as to allow the catalyst to be used in an acidic environment for a long time.

The invention provides a photocatalytic reaction method, comprising the steps of: atomizing a solution or suspension containing a photocatalyst and a reactant to form mist; and leading the mist to be subjected to photocatalytic reaction by utilizing a light source. The invention also provides a photocatalytic reaction device, which comprises a reaction vessel, an atomizer arranged inside or outside the reaction vessel, a condensation sleeve communicated with the reaction vessel, and the light source used for photocatalytic reaction. By means of the method and the device, a gas-liquid interface is enlarged by changing the form of water, i.e. atomizing the liquid-phase solution of the catalyst, so as to reduce the escape path of hydrogen gas and effectively inhibit the occurrence of reverse reaction, meanwhile, because the scattering probability of light in the mist is increased and the effective absorption is enhanced, the light utilization rate and the catalytic efficiency of the photocatalyst are greatly improved.

The invention discloses a Fenton-like catalyst of graphene coated ferriferrous oxide (Fe3O4) micro-spheres as well as a preparation method and application thereof. The preparation method comprises the following steps: completely coating Fe3O4 particles by graphene; by taking an aqueous solution of inorganic ferric salt and graphene oxide as a precursor, rapidly preparing graphene oxide coated ferric salt precursor micro-spheres by adopting a spray-drying technology, and performing calcination reduction at a protective atmosphere to obtain a target product. The Fenton-like catalyst of the graphene coated Fe3O4 micro-spheres, disclosed by the invention, has relatively good catalytic efficiency and very good stability under the coordination of a hydrogen peroxide aqueous solution, can also be acquired by virtue of simple external magnetic field separation to be recycled and repeatedly used, can be used for reducing cost, and is an environment-friendly material.

The invention discloses an inorganic antibacterial fiber of a coating layer and a preparation method thereof. The invention leads four-needle zinc oxide whisker that is blended with silver, ferric oxide, titanium dioxide or the mixture of the silver, the ferric oxide and the titanium dioxide to be modified, and expands the responsiveness of the four-needle zinc oxide whisker in the field of visible lights. The four-needle zinc oxide whisker or the modified four-needle zinc oxide whisker are loaded onto the fiber, and due to the special space structure, the four-needle zinc oxide whisker has strong holding power to the fiber and can be well loaded onto the fiber, thus well combining the high catalytic activity of the four-needle zinc oxide whisker and the high specific surface property of the fiber, greatly improving the catalytic efficiency of optical catalysts, and simultaneously solving the recycling problem of the optical catalysts.

The invention provides a Fe3O4-poly-dopamine-Au nano-composite material. Au nano-particles are deposited on the surfaces of Fe3O4 nano-magnetic beads covering poly-dopamine, wherein the diameter of the Au nano-particles is 10-30 nm; the thickness of poly-dopamine is 20-55 nm, and the diameter of Fe3O4 magnetic beads is 200-250 nm. The invention also provides a preparation method of the Fe3O4-poly-dopamine-Au nano-composite material and an application of the Fe3O4-poly-dopamine-Au nano-composite material in detection of catalysis of p-nitrophenol. According to the composite material, because nanogold is distributed on the surface layer of the Fe3O4-poly-dopamine-Au nano-composite material, the catalytic efficiency is improved; in addition, the Fe3O4 magnetic beads have the characteristics of high biocompatibility and environmental protection, and is convenient to synthesize and easy to separate, so that a nanogold catalyst can be repeatedly used.

The invention discloses an ozone-catalytic functional ceramic membrane, a preparation method thereof and a circulating coating device, relates to the technical field of membrane material preparation, and aims at solving the problems that the ozone-catalytic efficiency of the existing ceramic membrane is low, the integration of membrane filtration and ozone-catalytic functions cannot be realized, membrane pollution cannot be effectively relieved and the like. By using a tubular ceramic membrane as a carrier, single-component or multi-component metal oxides are loaded through an impregnation method, then manganese oxide dipping coating solution is prepared, and a catalytic coating layer is prepared on the surface of the membrane through a layer-by-layer dipping coating method. The invention aims at establishing a stereoscopic multistage catalyst system, simultaneously improving the catalytic efficiency of the separation layer and supporting layer of the ceramic membrane and enabling an ozone-catalytic effect to seep into the entire ceramic membrane to fully realize the overall catalytic effect. Compared with other metal oxides, manganese oxide has better adsorption and ozone-catalytic capacities, and while the ozone-catalytic capacity is improved, the membrane pollution is effectively relieved and the integration of multiple functions such as pollutant adsorption, ozone-catalytic oxidization and membrane separation is realized.