Umicore Shokubai Japan Co., Ltd.

Umicore Shokubai USA Inc.

Kosuke Mikita

Masanori Ikeda

Takahiro Ikegami

Hideki Goto

Hirotaka Kuno

Masashi Nakashima

Shigekazu Minami

Yuji Ogino

Shinji Sugihara

Masanori Mikita

In order to provide an exhaust gas purification catalyst capable of purifying hydrocarbons, carbon monoxide, and nitrogen oxides in exhaust gas at low temperatures, the exhaust gas purification catalyst according to the present invention includes: a region () containing palladium and yttrium on a three-dimensional structure (), and a first region () and a second region () provided on the region () in order from an inflow side of exhaust gas to an outflow side of exhaust gas. The concentration of yttrium contained in the first region () and/or the second region () is higher than the concentration of yttrium contained in the region ().

Exhaust gas purification catalyst and exhaust gas purification method using the same

In order to provide an exhaust gas purification catalyst capable of purifying hydrocarbons, carbon monoxide, and nitrogen oxides in exhaust gas at low temperatures, the exhaust gas purification catalyst according to the present invention includes: a region () containing palladium on a three-dimensional structure (), and a first region () and a second region () provided on the region () in order from an inflow side of exhaust gas to an outflow side of exhaust gas. The concentration of rhodium contained in the first region () is higher than the concentration of rhodium contained in the second region ().

Provided is a catalyst for purifying an exhaust gas, the catalyst excelling in catalytic performance and oxygen storage capacity. The catalyst for purifying an exhaust gas is a catalyst for purifying an exhaust gas which includes a ceria-zirconia composite oxide having a pyrochlore structure and a ceria-zirconia composite oxide having a cubic crystal structure, wherein at least a part of the ceria-zirconia composite oxide is composited with the ceria-zirconia composite oxide.

Catalyst for purifying exhaust gas

PROBLEM The present invention is directed to provide a catalyst for purifying exhaust gas capable of maintaining a superior catalytic performance even when the catalyst is exposed to an exhaust gas at a high temperature of 800&#xb0; C. or higher. SOLUTION The catalyst for purifying exhaust gas of the present invention comprises a catalytically active component containing a noble metal and a promoter containing an oxygen storage material both being supported on a carrier. The oxygen storage material comprises cerium, zirconium, and iron, and content of iron in the oxygen storage material is 0.01% by mass or more and less than 0.70% by mass (FeOconversion) relative to the total mass of the oxygen storage material. And the oxygen storage material is (a) a complex oxide or a solid solution of iron and a metal comprising cerium and zirconium; or (b) an iron is supported on a complex oxide or a solid solution of a metal comprising cerium and zirconium.

An Object of the patent is to remove highly reducing hydrocarbon exhausted during acceleration period, and to remove efficiently hydrocarbon even after contacting with highly reducing hydrocarbon. By using a catalyst having a higher proportion of palladium having surface charge of 2-valence or 4-valence supported than that of 0-valence by supporting palladium together with magnesium oxide, hydrocarbon exhausted from an internal combustion engine especially during acceleration period can be efficiently removed.

Catalyst for purifying exhaust gas from internal combustion engine and process for purifying exhaust gas using the same

An exhaust gas purification catalyst of the present invention contains at least a precious metal coated with lanthanum-containing alumina. In at least one embodiment, it is possible to provide: an exhaust gas purification catalyst which can (i) have an increase in heat resistance, and (ii) inhibit the precious metal from being mixed in alumina and therefore inhibit the precious metal from forming a solid solution in combination with alumina; and a method for efficiently purifying, by use of the catalyst, an exhaust gas emitted from an internal-combustion engine.

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Himeji, Japan

Kosuke Mikita