80results about How to "Maintain catalytic performance" patented technology

The average cycle propylene selectivity of an oxygenate to propylene (OTP) process using one or more fixed or moving beds of a dual-function oxygenate conversion catalyst with recycle of one or more C₄⁺ olefin-rich fractions is substantially enhanced by the use of selective hydrotreating technology on these C₄⁺ olefin-rich recycle streams to substantially eliminate detrimental coke precursors such as dienes and acetylenic hydrocarbons. This hydrotreating step helps hold the build-up of detrimental coke deposits on the catalyst to a level which does not substantially degrade dual-function catalyst activity, oxygenate conversion and propylene selectivity, thereby enabling a substantial improvement in propylene average cycle yield. The propylene average cycle yield improvement enabled by the present invention over that achieved by the prior art using the same or a similar catalyst system but without the use of the hydrotreating step on the C₄⁺ olefin-rich recycle stream is of the order of about 1.5 to 5.5 wt-% or more.

The invention provides a method for producing lactic acid by using glycerin and a special catalyst for the production of the lactic acid by using the glycerin. The catalyst provided by the invention is obtained by loading 0.1 to 30 mass parts of an active ingredient onto 100 mass part of carrier, wherein active ingredient is (1) Pt or (2) a composite of Pt and other noble metals. The catalyst can be used in the production of the lactic acid by using the glycerin. In the presence of the catalyst of the invention, the glycerin can be converted into the lactic acid effectively under a mild reaction condition. The catalyst of the invention has the advantages of high activity and selectively, easy preparation, low price, easy industrialization, long service life, loss prevention and good application prospective.

The invention relates to an X-shaped zeolite molecular sieve and a method for preparing thereof, relating to a field of zeolite molecular sieve material; The X-shaped zeolite molecular sieve is a magnetic iron-doped X-shaped zeolite molecular sieve; magnetic ferroferric oxide is formed in the zeolite lattice, wherein, quality percentage of Fe occupying the molecular sieve is 1.89 percent to 3.48 percent. The preparing method comprises the steps that, iron-doped X-shaped zeolite molecular sieve is firstly compounded and then the magnetized magnetic iron-doped X-shaped zeolite molecular sieve is prepared through hydrogen reduction; the method results in a structure of Fe3O4 formed in frame of the iron-doped X-shaped zeolite molecular sieve. The magnetic iron-doped X-shaped zeolite molecular sieve has strong magnetism and magnetic stability, which not only solves the problem that the existing powdery zeolite molecular sieve is difficult to be recycled in reaction solution, and further improves absorption property of the sieve, but also enlarge application range of the zeolite molecular sieve, thereby allowing the zeolite molecular sieve to be applied to catalytic reaction in which iron acts as the catalyst.

The invention discloses a preparation method of a catalyst for catalyzing ozonization and decomposition volatile organic compounds (VOCs) at normal temperature. The preparation method comprises the following steps: (1) loading nano rare earth oxide coating serving as an auxiliary agent on a catalyst carrier, coating an active component, namely nano perovskite, on the carrier, on which the rare earth oxide is loaded, calcining the catalyst carrier, on which the auxiliary agent and the active component are loaded, and forming a large amount of micropores in the surface of and inside the catalyst carrier to obtain a target catalyst with pores; and (2) fixing the prepared target catalyst on a catalytic bed layer of a catalytic oxidation tower, starting an ozone generator, introducing VOC waste gas subjected to pretreatment in the catalytic oxidation tower, and performing deep oxidation on the VOCs at normal temperature of -10 to 40 DEG C to generate non-toxic and odorless substances. By the method, the VOCs can be completely oxidized at room temperature to generate carbon dioxide and water, so the method is safe in operation and low in energy consumption.

The invention discloses a graphene superfine fiber polyurethane synthetic leather and a preparation method thereof. The graphene superfine fiber polyurethane synthetic leather comprises a surface layer, a middle layer and an adhering layer which are respectively prepared from the following components of high-performance waterborne non-yellowing polyurethane resin, nylon, graphene, superfine fiberpolyurethane synthetic substrate, an abrasion-resistant agent, a light-resistant agent, a flame-retardant master batch and pure water. The preparation method comprises the following steps of S1, weighing the raw materials according to a ratio; S2, treating the graphene; S3, mixing and stirring the raw materials; S4, filtering the solution by a filtering net, and preparing an automobile superfine fiber leather by a dry type synthetic leather production line. The prepared graphene superfine fiber polyurethane synthetic leather has the advantages that the comprehensive property is excellent, thetesting result in each aspect is good, the physical indexes are basically the same with the physical indexes of common superfine fiber automobile interior trim, the moisture and air ventilating property is realized, the abrasion-resistant property is excellent, and the touch feel of the natural leather is realized.

The invention relates to a method for preparing a nickel-copper (111) alloy single crystal film. The method comprises: S1, providing a sapphire base, S2, depositing a metal film with thickness of 50 to 5000 nm on the crystal plane Al2O3 (0001) of the sapphire base to obtain a sapphire substrate on which a nickel-copper alloy is deposited, wherein the metal film is an alloy thin film composed of 1-40% of nickel atoms, and copper atoms, and S3, putting the sapphire substrate in a chemical vapor deposition furnace and carrying out annealing treatment in a gas atmosphere of argon gas and hydrogengas to obtain a single crystal thin film with (111) crystal orientation. The invention also relates to a nickel-copper (111) alloy single crystal film obtained by the method. The nickel-copper (111) alloy single crystal film greatly improves the performances of graphene and lays a foundation for the application of graphene in the field of microelectronics.

The invention provides a carbon nitride-carbon-TiO2-selenium nano composite material applied to photocatalytic degradation of pollutants. According to the invention, an azide-modified nano-carbon nitride-nano-titanium dioxide composite material is covalently chelated to the surface of an alkynylation-modified multi-walled carbon nanotube-nano selenium composite material to obtain a carbon nitride-carbon-TiO2-selenium nano composite material. The material can be applied to photocatalytic degradation of pollutants and has excellent photocatalytic degradation properties for the pollutants.

The invention discloses a method for synthesizing trioxymethylene. The method comprises the following step of carrying out a reaction on the aqueous solution of formaldehyde under the presence of an ionic liquid and an accelerant, wherein the accelerant is a salt compound, and the mass percent of the aqueous solution of formaldehyde is 30-70%. The method disclosed by the invention has the advantages that (1) the accelerant is convenient to prepare and has a good acceleration effect; (2) the activity of the ionic liquid which serves as a catalyst can be improved significantly without affecting the selectivity of the product of reaction, and the use amount and the cost of the ionic liquid can be reduced under the condition that the catalytic performance is guaranteed; (3) the concentration of the formaldehyde which serves as a raw material is wide and ranges between 30wt.% and 70wt.%, and the reaction condition is mild; (4) the continuous distillation reaction is adopted, and the accelerant can be recycled; (5) the concentration of the product of reaction is wide, and the accelerant has low corrosivity and a significant accelerating effect and can be recycled.

The invention belongs to the technical field of catalysts, and discloses an iron-nitrogen-codoped porous carbon catalyst for a proton exchange membrane fuel cell and a preparation method of the iron-nitrogen-codoped porous carbon catalyst. The method comprises the following steps: (1) adding 2-fluoroaniline and a ferric iron salt to deionized water, and stirring the deionized water evenly to obtain a mixed liquid; (2) transferring the mixed liquid obtained in the step (1) to a hydrothermal reaction kettle for a hydrothermal reaction, and cooling, filtering, cleaning and drying the mixed liquid to obtain a 2-fluoroaniline flake; (3) putting the 2-fluoroaniline flake obtained in the step (2) into a quartz tube furnace, introducing nitrogen, warming to 750-850 DEG C, carrying out a thermal reaction for 2-3 hours, and cooling the 2-fluoroaniline flake to obtain the iron-nitrogen-codoped porous carbon catalyst. The prepared catalyst is large in specific surface area, good in catalytic property, high in anti-methanol poisoning capability, good in durability, high in stability and simple in preparation method, and can be applied to the field of the fuel cell.

The invention relates to a preparation method of the caffeine intermediate N,N-1,3-dimethyl-4,5-diamido urazine and belongs to the technical field of synthesis and preparation of organic compounds. According to the preparation method, a hydrogen addition reaction is carried out under heated and pressurized conditions with N,N-1,3-dimethyl-4-imido-5-isonitroso urazine as the starting material and raney nickel as the catalyst, an aqueous solution containing metal halide and alkaline substances is used as the reaction medium, the preparation method has the advantages of being smooth and controllable in reaction, high in catalytic activity and stable in quality of dimethyl-DAU, and the yield and the quality of the dimethyl-DAU are improved.

The invention discloses a catalytic purification and heat exchange system. The catalytic purification and heat exchange system comprises a shell, a heat exchanger main body, a separation element, a heat carrier, a flue gas channel and an air channel, wherein a cavity is defined by the shell; the heat exchanger main body is arranged in the cavity and can rotate around the central axis of the heat exchanger main body; the separation element is arranged in the heat exchanger main body along the central axis, and the heat exchanger main body is separated into a first containing part and a second containing part, which are opposite to each other; the heat carrier contains catalysts which are contained in the first containing part and the second containing part, respectively; the flue gas channel is communicated with one of the first containing part and the second containing part, and the air channel is communicated with the other one of the first containing part and the second containing part so as to enable air and the heat carrier contained in the containing parts to exchange heat. According to the catalytic purification and heat exchange system provided by the invention, harmful gases can be removed through continuous catalysis, or waste heat can be recycled in the denitrification process.

The invention discloses a granular titanium-silicon molecular sieve catalyst and a preparation method thereof. The granular titanium-silicon molecular sieve catalyst is prepared by using the following method: hydrochloric acid is added into water, the mixture is stirred and added with a glycol-propylene glycol-glycol copolymer, ethyl orthosilicate is dropped after the glycol-propylene glycol-glycol copolymer is dissolved, titanium-silicon molecular sieve fine powder is added into the mixture after the ethyl orthosilicate is completely hydrolyzed to be evenly mixed into a slurry state substance; and the slurry state substance is calcined for 5 to 30 hours in the air at 500 to 950 DEG C to obtain the granular titanium-silicon molecular sieve catalyst which has a middle hole, is covered with a silica gel layer and has a particle diameter of 5mu m to 75mu m. The granular titanium-silicon molecular sieve catalyst prepared by the invention has large particle diameter and high strength, is not easy to pulverize, is easy to separate after catalyzed reaction is completed, keeps the catalysis property of the titanium-silicon molecular sieve fine powder and is used for preparing propylene oxide by catalyzing propylene ring oxidation, and the oxydol conversion rate and the propylene oxide selectivity of the granular titanium-silicon molecular sieve catalyst approach to those of titanium-silicon molecular sieve fine powder.

The invention discloses a preparation method of a graphene-based iridium-copper nano composite material. The method comprises the following steps: 1, dissolving iridium salt and copper salt in deionized water to obtain a mixed solution; 2, adding graphene oxide powder into the mixed solution, and carrying out ultrasonic dispersion to obtain a turbid liquid; 3, atomizing and drying the turbid liquid to obtain graphene oxide-loaded mixed metal salt powder; and 4, carrying out synchronous thermal reduction treatment on the graphene oxide-loaded mixed metal salt powder to obtain the graphene-basediridium-copper nano composite material. According to the invention, a method of combining spray drying with synchronous thermal reduction is adopted, nano particles of iridium and copper mixed salt are uniformly loaded on the surface of the graphene oxide, the graphene-based iridium-copper nano composite material prepared by adopting the method has the advantages that agglomeration of nano particles of iridium and copper mixed salt is reduced, the number of active sites on the surface of the graphene-based iridium-copper nano composite material is increased, the catalytic performance of the graphene-based iridium-copper nano composite material is improved, the service life of the graphene-based iridium-copper nano composite material is prolonged, and the utilization efficiency of the graphene-based iridium-copper nano composite material is improved.

The invention discloses a self-heating coating type low-temperature denitration catalyst, and relates to the field of denitration catalysts. The self-heating coating type low-temperature denitration catalyst comprises a matrix and a catalyst coating, wherein the catalyst coating is arranged above the matrix, and the catalyst disclosed by the invention can be initially used as a normal low-temperature denitration catalyst, and can be subjected to electrifying self-heating online regeneration after ammonium bisulfate is inactivated. The invention further discloses a preparation method. Accordingto the preparation method disclosed by the invention, Al2O3 is deposited on the surface of an electrothermal metal alloy by utilizing an electro-deposition technology to form a transition layer film,the upper surface of the Al2O3 transition layer is coated with a catalyst slurry coating, and then roasting is carried out in an air atmosphere, so that the catalyst coating slurry is sintered on thesurface of the Al2O3 transition layer.

The invention relates to an SCR catalyst applicable to medium-and-high-temperature and high-humidity flue gas conditions and a preparation method thereof, belonging to the technical field of catalystpreparation. The preparation method comprises the following concrete steps: placing a cerium precursor, a molybdenum precursor and a carrier namely TiO2 with calculated amounts into a ball mill tank,carrying out ball milling for 1 to 6 h, and calcining a uniformly-mixed powder in a muffle furnace by two steps so as to obtain a MoO3-CeO2/TiO2 composite oxide catalyst, wherein the content of CeO2 accounts for 5 to 40 wt% of the total amount of a cerium-titanium composite oxide, and the content of MoO3 accounts for 0 to 10 wt% of the total amount of a molybdenum-cerium-titanium composite oxide.The SCR catalyst provided by the invention maintains an NO conversion rate to be 85% or above in a medium and high temperature range (250 to 500 DEG C) under a high-humidity flue gas condition. The preparation method provided by the invention has the advantages of simple preparation process, easily-controllable conditions, low raw material price, and potential application value in the field of denitration.

The invention discloses a nanometer rare earth catalyzed ozonation method for normal temperature digestion of volatile organic matters. The nanometer rare earth catalyzed ozonation method comprises: (1) loading a nanometer rare earth element coating adopted as an auxiliary agent on a catalyst carrier, coating nanometer spinel adopted as the active component of the catalyst on the obtained carrier, and finally calcining the catalyst carrier loading the auxiliary agent and the active component to form a large number of micro-pores on the surface and in the internal of the catalyst carrier so as to obtain a target catalyst with pores; and (2) fixing the prepared target catalyst on the catalytic bed layer of a catalytic oxidation tower, starting an ozone generator, introducing volatile organic matters into the catalytic oxidation tower, and carrying out deep oxidation on the volatile organic matters into non-toxic and odorless substances at a room temperature of -10-40 DEG C, wherein the volatile organic matters are pre-treated and acid gas, alkali gas and other dust and particles are removed from the volatile organic matters before the volatile organic matters are introduced into the catalytic oxidation tower. According to the present invention, with the method, the VOCs can be completely oxidized at the room temperature to produce carbon dioxide and water, such that the operation is safe, and the energy consumption is low.

The invention provides a preparation method of a fatty alcohol tertiary amine load type catalyst. The preparation method of the fatty alcohol tertiary amine load type catalyst comprises the followingspecific steps: premixing the following metal oxides and a carrier in parts by mass: 20-40 parts of copper oxide, 5-10 parts of nickel oxide, 0-10 parts of zinc oxide, 0-5 parts of magnesium oxide and35-75 parts of the carrier in a ball-miller, successively adding deionized water and a dispersing agent and dispersing and grinding for 1-4 hours, after filtering and drying, roasting for 2-4 hours at the temperature of 300-400 DEG C, and after grinding and hydrogen reduction, catalyzing fatty alcohol under the condition of normal pressure to react with dimethylamine so as to prepare tertiary aliphatic amine. A preparation process of the catalyst is simple, and is easy to operate, the preparation method is energy-saving and environmentally friendly, and the performance of the catalyst is good.

The invention discloses a preparation method of a supported carbon-coated bimetallic catalyst, which comprises the following steps: (1) weighing a supported bimetallic catalyst, uniformly mixing the supported bimetallic catalyst with water, adding an aqueous solution of a soluble saccharide carbon source compound and an aqueous solution of hydroxyethyl cellulose, dipping at room temperature for 0.5-10 hours, and carrying out vacuum drying until moisture is dried to obtain the supported bimetallic catalyst; a dried product is obtained; (2) carrying out high-temperature roasting on the dried product at 400-1000 DEG C in an inert atmosphere, a hydrogen atmosphere or a vacuum state for 2-20 hours to obtain a roasted product; and (3) reducing the temperature to 100-180 DEG C, and treating the roasted product in an air atmosphere for 4-10 hours to prepare the supported carbon-coated bimetallic catalyst. The catalyst prepared by the invention has a complete carbon layer wrapping metal active component with a proper structure and thickness, is used for preparing alkoxy substituted or phenolic hydroxyl substituted aniline compounds by hydrogenation rearrangement of nitrobenzene compounds, and has high stability and high target product selectivity.