11results about How to "Maintain catalytic activity" patented technology

The present application relates to a kind of catalyst for hydrogen chloride oxidation preparation chlorine and its preparation method and application.The preparation method includes: after carrier substrate, metal tantalum powder, binder solution are mixed, extrusion forming is obtained green body, the green body is prepared composite carrier by calcination, the mass fraction of metal tantalum powder in the composite carrier is 5%-30%;Inorganic salt containing catalytically active element is made into solution and is placed in the composite carrier, and after drying, pre-product is obtained, and the pre-product is prepared catalyst by calcination.The preparation method described in the present application prepares high thermal conductivity composite carrier, not only effectively improves the heat conduction efficiency of catalyst, guarantees the effective activity of catalyst, but also guarantees the stability of composite carrier, thereby effectively prolongs the life of catalyst.

The invention provides a fuel cell ORR catalyst and a preparation method and application thereof. The fuel cell ORR catalyst comprises a nitrogen-doped porous carbon core, a nitrogen-doped porous carbon coating layer arranged on the surface of the nitrogen-doped porous carbon core, and doped metal simple substances distributed in pore channels of the nitrogen-doped porous carbon core and the nitrogen-doped porous carbon coating layer, the ratio of micropores in the nitrogen-doped porous carbon core is gt; the total proportion of mesopores and macropores in the nitrogen-doped porous carbon core; the ratio of micropores in the nitrogen-doped porous carbon coating layer is lt; the total ratio of mesopores to macropores in the nitrogen-doped porous carbon coating layer is 1: 1. The nitrogen-doped porous carbon structure monatomic catalyst with multiple micropores inside and multiple mesopores / macropores outside is obtained through gradient pore channel design in space in combination with a CVD coating technology, and dissolution and loss of metal elementary substances are greatly inhibited while the catalytic activity of the catalyst is guaranteed, so that the service life of the catalyst is prolonged.

The application provides a method for preparing two-dimensional titanium dioxide microwires by using a high-viscosity system and application. The method comprises the following steps: providing a high-viscosity system, wherein the high-viscosity system is an aqueous solution of guar gum hydroxypropyltrimethyl ammonium chloride; and performing high-speed shearing treatment on the high-viscosity system; adding liquid tetrabutyl titanate into the high-viscosity system, stirring, centrifugal drying, and obtaining the two-dimensional titanium dioxide microwires. The preparation method is simple, reaction conditions are normal temperature and normal pressure, the method is easy to control, mass production is realized, and the prepared two-dimensional titanium dioxide microwires have good catalytic activity.

The application belongs to the field of petroleum refining catalysis technology, and discloses a ZSM-5 additive for increasing propylene production and a preparation and use method thereof. In the method, waste filtrate prepared by using SAPO-34 molecular sieve is used to improve the stability of the molecular sieve under a high-temperature water-containing atmosphere, prevent the molecular sieve channels from being blocked by excessive phosphorus elements, reduce environmental pollution caused by the waste filtrate, improve the specific surface area of the ZSM-5 additive and the stability of the product, realize the dual effects of the stabilization of the molecular sieve by the phosphorus elements and the protection of the organic ammonium channels, complement the low-molecular-weight ammonium polyacrylate, white carbon black and phosphorus aluminum binder, construct a hierarchical pore structure (micropore-mesopore-macropore hierarchical pore), and then obtain the additive with a specific surface area of 150-170 m 2 / g, an addition amount of only 10 wt% can achieve a propylene production effect better than that of 20 wt% of a commercially available additive, the catalyst procurement cost of a refinery is greatly reduced, and the slurry oil yield is reduced and the heavy oil cracking capacity is improved.

The application discloses a kind of photocatalytic nanocomposite and its preparation method and application, belong to nanocomposite technical field, first synthesis CuInS2 quantum dot powder, a layer of carbon is covered on the surface of CuInS2 quantum dot powder, then amino is introduced by silane coupling agent modification, then modified carbon composite CuInS2 quantum dot powder is loaded on tubular carbon nitride powder formed.The tubular structure of tubular carbon nitride powder is conducive to CuInS2 quantum dot dispersion on its surface or inside, so that the active site of CuInS2 quantum dot powder is fully exposed, the band gap energy of CuInS2 quantum dot powder is about 1.53eV, when being irradiated, electron and hole pair can be generated, can promote the separation of photoinduced electron and hole to improve the activity of catalyst, and the dense carbon layer on CuInS2 quantum dot powder can form physical barrier to prevent peroxide from directly contacting with sulfur ion.

The invention relates to the technical field of chemical catalysts, in particular to a catalyst for preparing 2-tert-butylhydroquinone and a preparation method and application thereof.The catalyst comprises a hierarchical pore H beta molecular sieve, active metal is loaded in a framework of the hierarchical pore H beta molecular sieve, and the active metal is one or more of La, Ce and Zn. The catalyst adopts the hierarchical pore H beta molecular sieve as a skeleton, so that the diffusion limitation of the traditional microporous molecular sieve can be effectively broken through, and the occurrence of side reactions is reduced while the intrinsic rate of the reaction is greatly improved. La, Ce and Zn active metals are introduced into a hierarchical pore H beta molecular sieve framework to form a high-activity catalytic center synergistic system, and the reaction process is enhanced. Compared with the traditional liquid acid catalyst and ion exchange resin, the catalyst has the characteristics of simple process, easiness in recovery, no pollution, good high-temperature stability, high catalytic activity, good selectivity and low cost, and solves the core problems of low activity, heavy pollution and high cost of the traditional catalyst.

A method for recovering organic tin in a vinyl ether compound transesterification kettle liquid, comprising the following steps: 1) taking the vinyl ether compound transesterification kettle liquid, cooling to-10-40 DEG C, standing, until crystals are precipitated in the transesterification kettle liquid, filtering, or, cooling to-10-40 DEG C, adding 0.1-5% of organic tin powder in mass fraction to the transesterification kettle liquid, stirring and mixing uniformly, then standing, until crystals are precipitated in the transesterification kettle liquid, filtering; 2) adding a basic solution with a concentration of 5-8 wt% to the crystals obtained by filtering, in a mass ratio of 1:0.5-10, and heating to 25-60 DEG C, until flocculent substances appear on the surface of the basic solution, and filtering the lower aqueous phase; 3) washing the crystals obtained by filtering with water, then washing with an organic solvent, drying, to obtain organic tin. The process condition is mild and the operation is convenient, the recovered organic tin can be used repeatedly, the production cost of enterprises is reduced, and environmental pollution is avoided.

The invention discloses an anti-static wafer PVCWafer protective film and a preparation method thereof, and belongs to the technical field of PVC thin films, hydroxyl on a polyborosiloxane molecular chain and silicon hydroxyl on the surface of modified nickel composite hollow carbon fiber are condensed, polyborosiloxane / hollow carbon fiber is used as rigid filler and can be uniformly dispersed in a polyvinyl chloride matrix, and the reason is that the rigid filler can be uniformly dispersed in the polyvinyl chloride matrix, so that the anti-static wafer PVCWafer protective film is prepared. Polyborosiloxane molecules contain a large number of silicon-oxygen bonds and boron-oxygen bonds, the groups have high polarity, compatibility with polyvinyl chloride can be improved, organosiloxane chain segments of polyborosiloxane have certain flexibility, the organosiloxane chain segments can serve as flexible buffer layers, rigidity difference between polyborosiloxane / hollow carbon fibers and polyvinyl chloride is relieved, and therefore the service life of the hollow carbon fibers is prolonged. The interface stress concentration is reduced, and the compatibility of the two is further improved.

This application relates to the field of catalytic conversion technology of organohalides, specifically disclosing a catalytic disproportionation reaction method for chlorofluorocarbons. The method includes the following steps: using two or more chlorofluorocarbons with different chlorine / fluorine atom numbers as raw materials, and reacting them in a closed reactor in the presence of aluminum chlorofluoride and / or amorphous aluminum fluoride catalyst at a temperature of 50-400℃ and a pressure of 0.1-5MPa for 1-24 hours, causing directional transfer and recombination of chlorine and fluorine atoms between the raw material molecules to generate a target product with a chlorine / fluorine atom number between that of the raw materials; wherein the aluminum chlorofluoride has the chemical formula AlCl₂. x F 3‑x 0 < x < 3; the chemical formula of the amorphous aluminum fluoride is AlF3·nH2O, where n is 0 or a positive integer. The target product is generated with high selectivity by promoting the exchange of chlorine / fluorine atoms between different CFC molecules through aluminum chlorofluoride and / or amorphous aluminum fluoride catalysts.

This invention discloses a method for preparing a platinum-manganese composite monolithic metal substrate catalyst, comprising the following steps: A. Surface treatment of the metal substrate; B. Preparation of a manganese-containing precursor solution; C. Immersion of the surface-treated metal substrate in the manganese-containing precursor solution to obtain a metal substrate with a thin active layer of manganese oxide; D. Immersion of the metal substrate with the manganese oxide active layer first in a platinum ethylenediaminetetraacetic acid complex solution, and then in a sodium borohydride solution I to obtain a metal substrate with platinum seed crystals deposited on its surface; E. Preparation of a platinum-containing precursor solution; F. Immersion of the metal substrate with platinum seed crystals deposited on its surface in the platinum-containing precursor solution, adding sodium borohydride solution II dropwise during the immersion process to obtain the platinum-manganese composite monolithic metal substrate catalyst. The catalyst prepared by the method of this invention exhibits high decomposition catalytic activity, long service life, and high cost-effectiveness.

This invention discloses a rhodium-silicon catalyst, its preparation method, and its application. The catalyst is a Rh / SiO2 catalyst, comprising a support, a silicon dioxide support, and an active component. The Rh species exist in one or more forms, namely Rh clusters or Rh nanoparticles formed by the aggregation of Rh clusters. Based on the total mass of the Rh / SiO2 catalyst, the loading of Rh species is 0.2-2.0 wt%; the average particle size of the Rh species is 0.7-2.0 nm. This invention uses a water-in-oil reverse microemulsion method to prepare the Rh / SiO2 catalyst in one step. By adjusting the loading of Rh, the average particle size of the Rh species can be controlled. When the Rh species in the catalyst of this invention exist in the form of Rh clusters with a particle size of 1.0 nm, its application in the heterogeneous catalytic hydroformylation of formaldehyde exhibits advantages such as high reactivity, high selectivity for ethanolaldehyde, high stability, and easy separation and recovery.