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公开(公告)号:US20210310391A1
公开(公告)日:2021-10-07
申请号:US17251942
申请日:2019-06-26
Applicant: CATALER CORPORATION
Inventor: Chihiro KASUYA , Yuji YABUZAKI , Masaaki KAWAI , Mitsuyoshi OKADA
Abstract: An exhaust gas purification catalyst device has catalyst coating layers, which extend from the upstream side to the downstream side of the exhaust gas flow. The catalyst coating layers each have at least three zones present in order from the upstream side to the downstream side of the exhaust gas flow, and each of these at least three zones is an oxidation catalyst zone or a reduction catalyst zone. In the uppermost layer of an oxidation catalyst zone, the total number of atoms of platinum and palladium is greater than the number of atoms of rhodium; in the upper most layer of a reduction catalyst zone, the number of atoms of rhodium is greater than the total number of atoms of platinum and palladium. The oxidation catalyst zones and the reduction catalyst zones alternate at least twice in the exhaust gas flow direction.