Patent classifications
B01J23/58
PROCESS FOR PRODUCING A POROUS ALPHA-ALUMINA CATALYST SUPPORT
A process for producing a porous alpha-alumina catalyst support, comprising i) preparing a precursor material comprising, based on inorganic solids content, at least 50 wt.-% of a transition alumina having a loose bulk density of at most 600 g/L, a pore volume of at least 0.6 mL/g and a median pore diameter of at least 15 nm; and at most 30 wt.-% of an alumina hydrate; ii) forming the precursor material into shaped bodies; and iii) calcining the shaped bodies to obtain the porous alpha-alumina catalyst support. The catalyst support has a high overall pore volume, thus allowing for impregnation with a high amount of silver, while keeping its surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The invention further relates to a shaped catalyst body for producing ethylene oxide by gas-phase oxidation of ethylene, comprising at least 15 wt.-% of silver, relative to the total weight of the catalyst, deposited on a porous alpha-alumina catalyst support obtained in the process described above. The invention also relates to a process for preparing a shaped catalyst body as described above comprising impregnating a porous alpha-alumina catalyst support obtained in the process described above with a silver impregnation solution, preferably under reduced pressure; and optionally subjecting the impregnated porous alumina support to drying; and b) subjecting the impregnated porous alpha-alumina support to a heat treatment; wherein steps a) and b) are optionally repeated. The invention further relates to a process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising reacting ethylene and oxygen in the presence of a shaped catalyst body as described above.
Metal-decorated barium calcium aluminum oxide and related materials for NH.SUB.3 .catalysis
This invention relates to a supported catalyst for synthesizing ammonia (NH3) from nitrogen gas (N2) and hydrogen gas (H2), method of making the support, and methods of decorating the support with the catalyst.
CONVERSION OF ALCOHOLS AND ALDEHYDES TO ENERGY-DENSE HYDROCARBON FUEL MIXTURES
The present disclosure relates to a process for preparing long-chain alkanes and alkenes from alcohols, aldehydes, or both. The process proceeds via acceptorless dehydrogenation and decarbonylative coupling using a supported catalyst.
Exhaust gas purification catalyst
Provided is an exhaust gas purification catalyst having an improved catalyst performance while securing an OSC in an air-fuel ratio (A/F) rich atmosphere where HC poisoning is likely to occur. The present disclosure relates to an exhaust gas purification catalyst including a substrate and a catalyst coating layer coated on the substrate. The catalyst coating layer has an upstream coat layer formed from an end portion in an upstream side with respect to an exhaust gas flow direction in the exhaust gas purification catalyst and a downstream coat layer formed from an end portion in a downstream side with respect to the exhaust gas flow direction in the exhaust gas purification catalyst. The downstream coat layer includes Rh as a catalytic metal, alumina-ceria-zirconia complex oxide, and alkaline earth metal.
Catalyst for removing nitrogen oxides
A catalyst for removing nitrogen oxides, and the catalyst for removing the nitrogen oxides includes a first catalyst having a component including Pt, Ba, and Ce supported on a first support, and a second catalyst physically mixed with the first catalyst and having a component including Cu and Ce supported on a second support.
EXHAUST GAS PURIFICATION DEVICE
Provided is an exhaust gas purification device that allows improving an exhaust gas purification performance. An exhaust gas purification device of the present disclosure includes a substrate and a catalyst layer disposed on the substrate. The catalyst layer contains a porous carrier, a catalytic metal that is supported by the porous carrier and belongs to platinum group, an alkaline earth metal supported by the porous carrier, and an alkaline earth metal not supported by the porous carrier. At least a part of the alkaline earth metal supported by the porous carrier is supported inside the porous carrier.
EXHAUST GAS PURIFICATION DEVICE
Provided is an exhaust gas purification device that allows improving an exhaust gas purification performance. An exhaust gas purification device of the present disclosure includes a substrate and a catalyst layer disposed on the substrate. The catalyst layer contains a porous carrier, a catalytic metal that is supported by the porous carrier and belongs to platinum group, an alkaline earth metal supported by the porous carrier, and an alkaline earth metal not supported by the porous carrier. At least a part of the alkaline earth metal supported by the porous carrier is supported inside the porous carrier.
Exhaust Gas Purification Catalyst
Provided is an exhaust gas purification catalyst that includes a base material containing a silicon-silicon carbide composite material and a catalyst layer containing a barium component and that has excellent high-temperature durability of oxygen storage capacity. The exhaust gas purification catalyst disclosed here includes a base material and a catalyst layer in contact with the base material. The base material contains a silicon-silicon carbide composite material. The catalyst layer contains a platinum-group catalyst, a barium component, and an oxygen storage material. The barium component is one material selected from the group consisting of barium and a barium compound. The barium component is present on at least a surface of the oxygen storage material. The barium component has an average particle size of 100 nm or more and 350 nm or less.
Exhaust Gas Purification Catalyst
Provided is an exhaust gas purification catalyst that includes a base material containing a silicon-silicon carbide composite material and a catalyst layer containing a barium component and that has excellent high-temperature durability of oxygen storage capacity. The exhaust gas purification catalyst disclosed here includes a base material and a catalyst layer in contact with the base material. The base material contains a silicon-silicon carbide composite material. The catalyst layer contains a platinum-group catalyst, a barium component, and an oxygen storage material. The barium component is one material selected from the group consisting of barium and a barium compound. The barium component is present on at least a surface of the oxygen storage material. The barium component has an average particle size of 100 nm or more and 350 nm or less.
Exhaust Gas Purification Catalyst
According to a technique disclosed herein, provided is an exhaust gas purification catalyst, which both suppresses OSC when using a new vehicle and maintains OSC during life cycles. The exhaust gas purification catalyst disclosed herein is an exhaust gas purification catalyst includes a substrate, and a catalyst coated layer formed on the surface of the substrate, wherein the catalyst coated layer contains an OSC material having an oxygen storage capacity. The catalyst coated layer includes a Rh layer mainly containing Rh as a catalyst metal, and a Pd/Pt layer mainly containing Pd and/or Pt as a catalyst metal. At least a portion of the Pd/Pt layer in the catalyst coated layer contains, as the OSC material, a low specific surface area OSC material, including a ceria-zirconia composite oxide and having a specific surface area of 40 m.sup.2/g or more and 60 m.sup.2/g or less.