摘要:
A porous metal-oxide composite particle suitable for use as a oxygen reduction reaction or oxygen evolution reaction catalyst and sacrificial support based methods for making the same.
摘要:
The present subject matter describes a catalyst composition based on sodium tantalate, a modifying agent and at least one co-catalyst and the process of preparing the catalyst composition. The process for photocatalytic reduction of CO2 comprises re-acting carbon dioxide and alkaline water in the presence of catalyst composition that is irradiated with radiation with wavelength in the range of 300-700 nm to produce lower hydrocarbons and hydrocarbon oxygenates.
摘要:
A catalyst layer including: (i) a first catalytic material, wherein the first catalytic material facilitates a hydrogen oxidation reaction suitably selected from platinum group metals, gold, silver, base metals or an oxide thereof; and (ii) a second catalytic material, wherein the second catalytic material facilitates an oxygen evolution reaction, wherein the second catalytic material includes iridium or iridium oxide and one or more metals M or an oxide thereof, wherein M is selected from the group consisting of transition metals and Sn, wherein the transition metal is preferably selected from the group IVB, VB and VIB; and the first catalytic material is supported on the second catalytic material. The catalyst can be used in fuel cells, supported on electrodes or polymeric membranes for increasing tolerance to cell voltage reversal.
摘要:
Disclosed are solid titanium-free Fischer-Tropsch catalysts including iron homogeneously modified with a zirconium promoter/stabilizer. The homogeneously mixed solid catalysts can be formed through co-precipitation of iron and zirconium precursors followed by calcination and reduction to form the active catalyst materials. The catalysts can optionally include additional materials such as copper, potassium, and silicon promoters.
摘要:
A particulate material is ground more efficiently using a mixture of at least two different sizes of yttrium-stabilized zirconia balls. The method facilitates preparation of photocatalysts with high activity.
摘要:
A nanostructure comprised of a primary layered non-cylindrical nanostructure support and at least one type of secondary substantially graphitic nanostructure grown therefrom. Both the primary layered nanostructure support and the layered substantially graphitic secondary nanostructure are substantially crystalline, wherein the secondary nanostructure, which will preferably be carbon, has a smaller diameter than the primary non-cylindrical nanostructure.
摘要:
The present invention relates to methods for producing metal-supported thin layer skeletal catalyst structures, to methods for producing catalyst support structures without separately applying an intermediate washcoat layer, and to novel catalyst compositions produced by these methods. Catalyst precursors may be interdiffused with the underlying metal support then activated to create catalytically active skeletal alloy surfaces. The resulting metal-anchored skeletal layers provide increased conversion per geometric area compared to conversions from other types of supported alloy catalysts of similar bulk compositions, and provide resistance to activity loss when used under severe on-stream conditions. Particular compositions of the metal-supported skeletal catalyst alloy structures can be used for conventional steam methane reforming to produce syngas from natural gas and steam, for hydrodeoxygenation of pyrolysis bio-oils, and for other metal-catalyzed reactions inter alia.
摘要:
The present invention concerns a catalyst for carrying out hydrocarbon synthesis starting from a mixture comprising carbon monoxide and hydrogen, the active phase of which comprises at least one metal from group VIII deposited on a support formed by at least one oxide, in which said metal from group VIII is selected from the group constituted by cobalt, nickel, ruthenium or iron, and in which said catalyst has an atomic ratio (Co/Al)not ground/(CO/Al)ground, measured by X-ray photo-emission spectroscopy, in the range 1 to 12.The invention also concerns the catalyst preparation process and its use.
摘要:
Catalysts and methods for alkane oxydehydrogenation are disclosed. The catalysts of the invention generally comprise (i) nickel or a nickel-containing compound and (ii) at least one or more of titanium (Ti), tantalum (Ta), niobium (Nb), hafnium (Hf), tungsten (W), yttrium (Y), zinc (Zn), zirconium (Zr), or aluminum (Al), or a compound containing one or more of such element(s). In preferred embodiments, the catalyst is a supported catalyst, the alkane is selected from the group consisting of ethane, propane, isobutane, n-butane and ethyl chloride, molecular oxygen is co-fed with the alkane to a reaction zone maintained at a temperature ranging from about 250° C. to about 350° C., and the ethane is oxidatively dehydrogenated to form the corresponding alkene with an alkane conversion of at least about 10% and an alkene selectivity of at least about 70%.
摘要:
A substantially pure phase LaTaO4 photocatalyst is prepared by grinding precursors with mixture of at least two different sizes of high-density yttrium-stabilized zirconia balls to a very fine particle size and calcining the ground precursors. The LaTaO4 photocatalyst prepared by this method is useful in photolysis of water.