62 results about "Pt based catalysts" patented technology

The invention discloses a N-doped porous carbon coated Fe and Co bi-metal nanoparticle catalyst and a preparation method of the N-doped porous carbon coated Fe an Co bi-metal nanoparticle catalyst, and belongs to the field of energy materials and electrochemistry. The catalyst takes glucose as the C source, g-C3N4 as the N source, the C source and the template, F3Cl3.6H2O and Co(NO3)2.6H2O are metal sources, a high-temperature stepwise calcining method is used to prepare the N-doped porous carbon coated Fe and Co Fe-Co@NC catalyst, and the catalyst is in a three-dimensional porous unordered stacking structure. Fe and Co exists in the forms of Fe0.3Co0.7, Fe2O3, and Co, and is evenly coated in the N-doped porous carbon. Compared with the commonly used Pt-based catalyst, the ORR (Overall Response Rate) performance in an alkaline medium is not much different from that of the commercial Pt / C catalysis, the OER (Oxygen Enhancement Ratio) performance is far better than that of the Pt / C catalyst, and the stability and the methanol tolerant property are better. Compared with the commonly seen bi-metal alloy catalyst, the catalyst has more active species, and the specific surface area is larger. In addition, the cost of the raw materials of the catalyst is low, the source of the raw materials is wide, the preparation process is simple and is favorable for large-scale production, and thecatalyst has a higher practical value.

The invention discloses a method for preparing a proton-exchange membrane fuel cell oxygen reduction catalyst based on PtNi (111) octahedral single crystal nanoparticles, which mainly solves the problem in the prior art that a conventional single-Pt catalyst or a Pt-based catalyst based on bimetallic spherical core-shell-structured nanoparticles is low in activity and poor in Pt atomic efficiency. Meanwhile, the influence factor and the synthesis optimization condition for morphology-controlled PtNi (111) octahedral single crystal nanoparticles are obtained. According to the technical scheme of the invention, platinum acetylacetonate and nickel acetylacetonate are adopted as metal salt precursors, and N, N-dimethylformamide (DMF) is adopted as a crystal face growth control agent. Through the heating reduction process, morphology-controlled PtNi (111) octahedral single crystal nanoparticles are obtained. The morphology-controlled PtNi (111) octahedral single crystal nanoparticles are subjected to ultrasonic dispersion in n-hexane, and then the well dispersed sol is slowly added onto the conductive carbon black of high specific surface area drop by drop through the residual titration process. Therefore, the electro-catalysis specific activity of the obtained oxygen reduction catalyst is high up to 1.5 A / mg Pt, and is improved by 9-10 times compared with that of conventional commercial Pt / C catalysts.

The invention discloses a preparation method of a metal organic framework loaded Pt-base catalyst. The method comprises putting the metal organic framework into an alcoholic solution, vibrating with ultrasonic, adding drop by drop a mixed solution of chloroplatinic acid and cobalt oxide, adding NaOH, stirring, putting into a microwave oven for intermittent heating, cooling, filtering by pumping, and drying under vacuum to obtain the metal organic framework loaded Pt-base catalyst. The catalyst is small in particle, not easy to agglomerate, good in dispersibility and high in electrochemical catalytic activity.

A catalyst for producing a liquefied petroleum gas according to the present invention comprises a Pd- and / or Pt-based catalyst component and a USY-type zeolite. By using the catalyst, a hydrocarbon containing propane or butane as a main component, i.e. a liquefied petroleum gas, can be produced with high activity, high selectivity and high yield from at least one of methanol and dimethyl ether.

The invention relates to a prussian blue-based high-stability high-activity Pt-based catalyst for a fuel cell and a preparation method thereof, and relates to the Pt-based catalyst for the fuel cell and the preparation method thereof, aiming at achieving the purposes of stability and activity of a cathode catalyst of the fuel cell. The catalyst is a composite catalyst which comprises Pt, the prussian blue and a carrier, wherein the weight ratio of the Pt to the prussian blue is (1-20) to 1, and the weight ratio of the Pt to total amount of the composite catalyst is (2.5-60) to 100. Compared with commercial Pt / C, the Pt-based composite catalyst disclosed by the invention has the advantages that the stability and the activity are greatly promoted, and a related Pt-prussian blue synergetic mechanism is provided for the first time to explain the promotion of the stability and the activity.

The invention discloses a preparation method of proton exchange membrane fuel cell negative electrode catalyst with defect-structure nitrogen / sulfur co-doped porous carbon aerogel, and belongs to thefield of a fuel cell. In the carbon aerogel, the PEMFCs negative electrode catalyst is successfully prepared by taking carrageenan and urea as raw materials. The carbon aerogel is provided with a richdefect structure and a nitrogen and sulfur heteroatom co-doped and hierarchical porous structure, and excellent oxidization-reduction reaction (ORR) catalytic activity is shown (a half-wave potentialunder 0.5M of H2SO4 electrolyte is 0.76V); and the ORR activity of a traditional heteroatom-doped carbon material under an acid electrolyte is not ideal compared with commercial Pt / C, thus, the ORR catalytic performance of the negative electrode catalyst under the acid condition is improved, and the negative electrode catalyst has important significance when applied to the PEMFCs instead of a previous metal Pt-based catalyst. In the negative electrode catalyst, the carrageenan is rich in source, and the nitrogen / sulfur co-doped porous carbon aerogel having the defect structure is excellent inORR catalytic performance and is a potential energy conversion material.

The invention discloses a catalyzing method of benzene hydrogenation at low temperature and a special catalyst thereof. The catalyzing method of the benzene hydrogenation at the low temperature provided by the invention uses a co-based catalyst to catalyze the benzene hydrogenation to react; wherein, the co-based catalyst is a cobalt single metal catalyst / or a noble metal-cobalt bimetal catalyst. Compared with a Ni-based catalyst or a Pt-based catalyst which is used for catalyzing the benzene hydrogenation to react at present, the invention can realize the benzene hydrogenation reaction at low temperature or even under condition of room temperature by using the co-based catalyst to catalyze the benzene hydrogenation to react and is provided with high hydrogenation activity. The invention provides a novel co-based catalyst, namely the noble metal-cobalt bimetal catalyst which is used in the benzene hydrogenation reaction. The noble metal-cobalt bimetal catalyst is provided with higher hydrogenation activity than the cobalt single metal catalyst. Besides being used in the preparation of cyclohexane, the co-based catalyst can be used in the intensive removal of aromatics, in particular the benzene in the fuel oil and the elimination of trace benzene in the environment.

The invention discloses a Pt based catalyst highly dispersed in a carrier SiO2 as well as a preparation method and application thereof. The catalyst takes SiO2 as the carrier, takes metal Pt as an active component, and takes NiO, La2O3 and LaFeO3 as auxiliaries; based on the total mass of the catalyst, the Pt based catalyst is prepared from the following components in percentage by mass: 0.1-0.3%of metal Pt, 0.05-4% of NiO, 0.25-9.0% OF La2O3, 17.0-30.0% of LaFeO3 and 55.0-85.0% of SiO2, and the catalyst can be applied to isobutylene dehydrogenation. The selected SiO2 has a big specific surface area, so that each component can be highly dispersed, and therefore, the catalyst is not liable to gather and sinter; meanwhile, Pt is doped into a perovskite structure, so that the reduced Pt particles are small, and perovskite particles, lanthanum oxide particles and nickel oxide particles among the Pt particles achieve the dispersion effect as a result of the special structure of perovskite,and therefore, more active sites are exposed; and Pt is not liable to reunite at a high temperature, so that stability and reaction activity of the catalyst are improved.

The invention discloses a method for preparing modified Pt-based catalysts with La loaded by metal organic framework materials used as carriers and application of the modified Pt-based catalysts. Themethod includes adding deionized water into terephthalic acid, chromic nitrate nonahydrate and hydrofluoric acid mixtures to obtain first mixtures; crystallizing the first mixtures for a period of time and then filtering and drying the first mixtures; adding N, N-dimethylformamide into the first mixtures and carrying out stirring reaction; filtering, washing and drying reaction products to obtainthe metal organic framework materials which are used as the carriers; adding chloroplatinic acid aqueous solution and precursor salt into the metal organic framework materials; carrying out reaction,then drying and calcining reaction products and carrying out reduction on the reaction products to obtain the ultimate required modified Pt-based catalysts La-Pt / MIL-101. The method and the application have the advantages that the modified Pt-based catalysts are low in cost, high in universality, free of equipment corrosion and good in cycle performance and are economical, effective and environmentally friendly; the modified Pt-based catalysts are high in activity and para amino phenol selectivity under relatively mild reaction conditions when applied to processes for preparing para amino phenol by means of nitrobenzene one-step hydrogenation rearrangement, production conditions can be improved, the production cost can be reduced, and the quality of products can be enhanced.