40results about How to "Good catalytic activity and stability" patented technology

A method of synthesizing titanium silicate molecular sieve is to hydrothermally crystallize the hydrolytic solution of silicon and titanium in a closed reaction vessel and then recycle the product. The method is characterized in that the hydrolytic solution of silicon and titanium is gotten by any one of the following three methods: A. under ultrasonic agitation, silicon source is first hydrolyzedin organo-alkali compound solution and then the titanium source is hydrolyzed in the solution; B. under the ultrasonic agitation, titanium source is first hydrolyzed in organo-alkali compound solution and then the silicon source is hydrolyzed in the solution; C. under the ultrasonic agitation, silicon source and titanium source are respectively hydrolyzed in organo-alkali compound solution and then mixed together. The synthetic method can eliminate partial uneven concentration, leads the amount of TiO2 generated by self agglomeration after the hydrolysis of titanium source to be as little as possible and reduces the production of extra framework titanium. Compared with the prior art, the TS-1 molecular sieve synthesized by the method not only has better catalytic oxidation activity and selectivity but also has better stability of catalytic activity.

The present invention provides a catalyst for water phase hydrogenation preparation of cyclopentanone from furfural or furfural alcohol and a preparation method thereof, the catalyst is a supported catalyst comprising an active ingredient and a carrier; the active component is one or two substance selected from Cu, Ni, Ru, Pd or Pt; the carrier is a magnetic iron oxide with the formula of FeyOx, wherein the ratio y / x is greater than 2/3 and less than 1; and the mass of the active ingredient 2. 0 to 10.0% of the carrier mass. The present invention also discloses a method for water phase hydrogenation preparation of cyclopentanone from furfural or furfural alcohol by use of the catalyst. The method has the advantages of simple operating steps and easy controlled operating conditions. The synthesized catalyst has good catalytic effect, high cyclopentanone product selectivity, and magnetic property, a magnet is used to attract the catalyst, separation and recovery of the catalyst are facilitated, and the catalyst has good prospects.

The invention belongs to the field of titanium silicon molecular sieve, and more specifically provides a titanium silicon molecular sieve, and a synthetic method and applications thereof. The titaniumsilicon molecular sieve is composed of crystal particles with a particle size ranging from 5 to 200nm via aggregation; the particle size of the titanium silicon molecular sieve ranges from 0.3 to 5<mu>m; the I960/I550 value ranges from 0.7 to 0.85. The invention also provides a cyclic ketone oxidation method. The cyclic ketone oxidation method comprises a step of contact of cyclic ketone, and anoxidizing agent with a catalyst. The catalyst contains the titanium silicon molecular sieve. The crystal of the titanium silicon molecular sieve is high in I960/I550 value, and is large in effective framework ti content. When the titanium silicon molecular sieve is used in oxidation reaction, the catalytic oxidation activity, and the reaction product selectivity are increased obviously, and excellent catalytic stability is achieved. The titanium silicon molecular sieve is capable of realizing aggregation of small crystal particles in crystallization growth process instead of simple physical aggregation of the small crystal particles, and micron order is achieved.

The invention relates to an electrocatalyst of a negative electrode of a fuel cell as well as a preparation method and application of the electrocatalyst. The catalyst adopts a conductive polymer as a reaction precursor, the conductive polymer is polymerized under the acid and oxidation condition to obtain polyaniline, the polyaniline is additionally provided with transition metal salt, and a phosphorus compound and/or a boron compound as a precursor, and the mixture is dried and is subjected to pyrolysis at the high temperature to obtain the electrocatalyst. The catalyst is N, phosphorus and/or boron co-doped nanometer carbon with a porous nanometer structure; the total mass percent of the doped heteroatom is 0.2 to 15 percent, the mass ratio of N to phosphorus and/or boron is 5:1 to 100:1, the weight percentage of metal is 0.1 to 10 percent, and the mass percent of the nanometer carbon is 75.0 to 99.7 percent.

A method for synthesizing a TS-1 molecular sieve comprises the steps that: (1) the aqueous solution of solid silica gel particles, titanium source and organo-alkali compound is mixed and treated with hydro-thermal treatment at 80-180 DEG C for 3-96 hours, wherein, the molar ratio of SiO2: TiO2: organo-alkali compound: water is 1: 0.001-0.5: 0.01-0.5: 5-100; (2) the aqueous solution of the solid silica gel particles, the titanium source and the organo-alkali compound is mixed until the titanium source is completely hydrolyzed; wherein, the molar ratio of SiO2: TiO2: organo-alkali compound: water is 1: 0.001-0.5: 0.001-0.80: 5-150; (3) the products obtained from step (1) and step (2) are mixed; and crystallization reaction is carried out by a conventional method to recover the product; wherein, the product of step (1) accounts for 10-80 percent. The method of the invention can synthesize the TS-1 molecular sieve with certain granularity, and the synthesized molecular sieve has low content of non-skeleton titanium and has high activity, stability and selectivity when being used in oxidation reaction.

The invention addressed two critical issues in fuel processing for fuel cell application, i.e. catalyst cost and operating stability. The existing state-of-the-art fuel reforming catalyst uses Rh and platinum supported over refractory oxide which add significant cost to the fuel cell system. Supported metals agglomerate under elevated temperature during reforming and decrease the catalyst activity. The catalyst is a perovskite oxide or a Ruddlesden-Popper type oxide containing rare-earth elements, catalytically active firs row transition metal elements, and stabilizing elements, such that the catalyst is a single phase in high temperature oxidizing conditions and maintains a primarily perovskite or Ruddlesden-Popper structure under high temperature reducing conditions. The catalyst can also contain alkaline earth dopants, which enhance the catalytic activity of the catalyst, but do not compromise the stability of the perovskite structure.

The invention provides a Cu-ZnO/SiO2 aerogel bimetallic catalyst, as well as a preparation method and application of the Cu-ZnO/SiO2 aerogel bimetallic catalyst. The preparation method comprises the following steps: weighing a SiO2 aerogel, adding the SiO2 aerogel into deionized water, stirring evenly at the constant temperature, dropwise adding a mixed aqueous solution of Cu(NO3)2.3H2O and Zn(NO3)2.6H2O; dropwise adding a Na2CO3 solution, stabilizing the pH value to 7.3-7.7; filtering, washing with the deionized water, drying overnight, roasting, tableting a sample, screening, and preparing a catalyst parent; conducting pretreatment of reduction activation on the catalyst parent in mixed gases of nitrogen and hydrogen, raising the temperature to 240 DEG C through a program at the speed of 2 DEG C per minute at the pressure of 0.1 MPa, wherein the volume fraction of H2 is 10%; raising the temperature to 300 DEG C through a program at the speed of 1.0 DEG C per minute, regulating the volume fraction of H2 to 30%, reducing for 6 hours at the constant temperature of 300 DEG C to obtain the reduced catalyst, namely the Cu-ZnO/SiO2 aerogel bimetallic catalyst. The distinguishing characteristic of the Cu-ZnO/SiO2 aerogel bimetallic catalyst and the preparation method is that the preparation process of the adopted SiO2 aerogel bimetallic catalyst is simple, and the SiO2 aerogel bimetallic catalyst is excellent in catalytic activity and stability in the reaction process.

The invention relates to a method for preparing a load type nanogold catalyst, which comprises the following steps: weighing a polyoxypropylene/polyoxyethylene copolymer solution and dissolving in deionized water to form a haze-free solution A; mixing a formaldehyde aqueous solution with concentration of 37wt.% and deionized water to obtain a haze-free solution B, then adding melamine and thiourea for stirring to obtain a solution C; dumping the solution A in the solution C for stirring to obtain a solution D, dissolving soluble glass in deionized water to obtain a solution E, rapidly dumping the solution D in acetate acid gracial, dumping the solution E in the solution D, performing microwave heating and soxhlet extraction by ethanol to obtain a mesoporous organic-inorganic interpenetrating network material, and dispersing in deionized water, then adding a HAuCl4 aqueous solution with concentration of 0.24M drop by drop, using NaOH with concentration of 1M to adjust pH value to 7-8, stirring, and filtering to obtain the load type nanogold catalyst. The load type nanogold catalyst has advantages of good catalytic activity and stability, the chemical materials with cheap price can be used for preparing the load type nanogold catalyst, and the load type nanogold catalyst enables multitime usage.

The invention belongs to the preparation field of catalysts, and in particular relates to a C@TiO2 solid acid catalyst in a core-shell structure and a preparation method of the C@TiO2 solid acid catalyst. The main preparation process is as follows: reacting biomass and tetrabutyl titanate serving as raw materials for 6-24 hours at 100-200 DEG C, drying and pyrolyzing the product to obtain a catalyst precursor in the core-shell structure, sulfonating the catalyst precursor through sulfuric acid, and drying to obtain the C@TiO2 solid acid catalyst in the core-shell structure. The catalyst has good catalysis activity and stability in acid alcohol esterification and transesterification. The raw material for the catalyst disclosed by the invention is cheap and easy to obtain, the performance is stable, and the large-scale production can be realized. Furthermore, the catalyst solves the common fault that the normal metallic oxide solid acid catalyst is easy to inactivate, and meanwhile, the acid density is increased, so that the acid strength is greatly prompted, the catalysis effect is good, and the catalyst is reusable and environmentally friendly.

The invention provides a carbon nitride based material for photocatalytic water total decomposition as well as preparation and application thereof. The carbon nitride based material for the photocatalytic water total decomposition, provided by the invention, is characterized by comprising a carbon nitride carrier; and monatomic palladium is loaded on the carbon nitride carrier. Compared with puregraphite-phase carbon nitride and palladium nanoparticle loaded carbon nitride, the carbon nitride based material provided by the invention has better catalytic activity and stability.

The invention belongs to the technical field of zinc air batteries, and particularly relates to a three-function heterostructure catalyst as well as a preparation method and application thereof. The three-function heterostructure catalyst comprises carbon cloth and a composite material layer arranged on the surface of the carbon cloth, the composite material layer comprises CoSe2 nanotubes, and the CoSe2 nanotubes are coated with an MNi LDH material; m is any one of cobalt, iron and manganese. According to the three-function heterostructure catalyst disclosed by the invention, a three-dimensional branch nanostructure array is constructed by compounding MNi LDH and CoSe2 nanotubes, so that the catalyst has more active sites and higher conductivity, thereby showing better catalytic activity and stability, and the three-function heterostructure catalyst can be used for preparing an electrolytic water electrode material and a zinc air battery.

The invention discloses a preparation method for sol-gel one-step low-temperature synthesis of a pure-phase Bi25F3O40/ZnO photocatalyst. The photocatalyst is applied to degradation reaction of low-concentration phenol aqueous solution under simulated sunlight. The photocatalyst is prepared according to a sol-gel method by steps: taking glycine as a complexing agent for complexing reaction of Fe(NO3)3.9H2O, Bi(NO3)3.5H2O and Zn(NO3)2.6H2O, calcining at 500 DEG C for 3h under the air atmosphere to form a semiconductor catalyst, wherein a ratio of amount of substance of Fe to Bi to Zn is 1:1:4, and a mole ratio of glycine serving as the complexing agent to total metal ions is 1:2. The pure-phase Bi25F3O40/ZnO photocatalyst is synthesized at a low temperature by sol-gel one-step preparation with glycine serving as the complexing agent. The preparation method is convenient and simple in operation and low in cost and is high in catalytic activity and structural stability in application to degradation of the low-concentration phenol aqueous solution.

The invention discloses a preparation method of a pure water cracking semiconductor catalyst for realizing visible light response by bimetallic ion co-doped strontium titanate, which comprises the following steps: conventionally mixing a (III) IA source compound and a (III) IB source compound with a common chemical containing Sr and Ti elements in proportion, and carrying out chemical complexation through simple heating treatment to obtain the pure water cracking semiconductor catalyst. And the double metal ion co-doped SrTiO3 body is directly synthesized. The preparation method comprises the following steps: uniformly mixing SrTiO3 with SrCl2, carrying out a certain thermal insulation heat treatment, removing excess SrCl2 by using a large amount of water to obtain a target product, and synthesizing the bimetallic ion co-doped SrTiO3 with specific morphology of (III) and (III) , the molar ratio of (III) ions is 0.1-0.5%, the molar ratio of (III) ions is 0.1-0.5%, and RhCrOx and CoOOH are loaded as cocatalysts. The reaction conditions are mild and safe, and the used reagents are low in price.