A catalyst comprising palladium, a porous support comprising at least one refractory oxide selected from the group constituted by silica, alumina and silica-alumina, the palladium content in the catalyst being in the range 0.01% to 2% by weight with respect to the total catalyst weight, at least 80% by weight of the palladium being distributed in a crust at the periphery of said support, the thickness of said crust being in the range 20 to 100 m, characterized in that said support is in the form of an extrudate and in that said support comprises a specific surface area in the range 165 to 250 m.sup.2/g.

A method for preparing acrylic acid, more specifically, to a method for preparing acrylic acid under a neutral condition at high yield in a short time without using a base, unlike the prior art in which a base is essentially used. The acrylic acid is produced using a supported catalyst having a specific composition when preparing acrylic acid by oxidation of allyl alcohol. Particularly, the preparation method can recover acrylic acid rather than acrylic acid salt as a final product, and thus has an advantage that the overall process cost can be reduced by eliminating essential processes in the prior art, such as ion exchange after the acidification process required for the conversion of acrylic acid salt to acrylic acid.

The present invention is in the field of catalysis. More particularly, the present invention is directed to supported precious metal catalysts, preferably palladium and/or platinum metal catalysts, having a high metal loading, a high degree of dispersion and a high degree of edge-coating. The present invention is further directed to a process for producing these catalysts, as well as to the use of these catalysts in chemical reactions.

An object of the present invention is to provide ferrite particles for supporting a catalyst having a small apparent density, various properties are maintained in a controllable state and a specified volume is filled with a small weight, and a catalyst using the ferrite particles for supporting a catalyst. To achieve the object, ferrite particles for supporting a catalyst provided with an outer shell structure containing Ti oxide, a catalyst using the ferrite particles for supporting a catalyst are employed.

A catalyst composition contains an inorganic porous material with pore diameters of at least 2 nm and of crystals of molecular sieve. The crystals of molecular sieve have an average diameter, measured by scanning electron microscopy, not bigger than 50 nm. The catalyst composition has a concentration of acid sites ranges from 50 to 1200 mol/g measured by TPD NH3 adsorption. An XRD pattern of the catalyst composition is the same as an XRD pattern of the inorganic porous material.

Methods for producing nanostructures from copper-based catalysts on porous substrates, particularly silicon nanowires on carbon-based substrates for use as battery active materials, are provided. Related compositions are also described. In addition, novel methods for production of copper-based catalyst particles are provided. Methods for producing nanostructures from catalyst particles that comprise a gold shell and a core that does not include gold are also provided.

The present invention is in the field of catalysis. More particularly, the present invention is directed to supported precious metal, preferably palladium and/or gold metal catalysts, having a high degree of dispersion and a high degree of edge-coating. The present invention is further directed to a process for producing these catalysts, as well as to the use of these catalysts in chemical reactions.

A structured catalyst for steam reforming of the present disclosure is used for producing reformed gas containing hydrogen from a reforming raw material containing hydrocarbon, and includes a support having a porous structure constituted of a zeolite-type compound, and at least one catalytic substance present inside the support. The support includes channels connecting with each other, and the catalytic substance is metal nanoparticles and present at least in the channels of the support.

A method of manufacturing a layered catalyst for purifying an exhaust gas stream includes introducing a mixture of colloidal ceria, alumina particles, and a liquid medium into a drying chamber via an atomizer to form atomized droplets of the mixture. A drying gas is introduced into the drying chamber such that the atomized droplets contact the drying gas, the liquid medium is removed from the atomized droplets, and ceria nanoparticles deposit on the alumina particles to form composite catalyst support particles. A catalyst precursor including a rhodium precursor and colloidal ceria is applied to the composite catalyst support particles. The composite catalyst support particles and the catalyst precursor are heated to form the layered catalyst. The layered catalyst includes an alumina substrate, a ceria nanoparticle layer extending substantially continuously over the alumina substrate, and a rhodium catalyst layer including an atomic dispersion of rhodium adsorbed on the ceria nanoparticle layer.

A method for producing a dispersion of metal-containing particles includes contacting a metal-supported material obtained by supporting a metal and/or a metal compound on a carrier with a polymeric protective agent showing affinity for the metal and/or the metal compound in a solvent to obtain a dispersion of metal-containing particles in which the metal and/or the metal compound is dispersed in the solvent in the form of particles.