Abstract: A catalyst for purification of exhaust gas containing a phosphorus compound includes: a lower catalyst layer containing at least one of noble metal provided on a refractory three-dimensional structure; and an upper catalyst layer at an inflow side of exhaust gas and an upper catalyst layer at an outflow side of exhaust gas provided on a surface of the lower catalyst layer. The upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side have different concentrations of noble metal. The catalyst has an intermediate zone with a length of 3 to 23% of the overall length of the refractory three-dimensional structure provided between the upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side. The intermediate zone starts from a position 10 to 38% from an end face of the catalyst at the inflow side of exhaust gas.

Abstract: The present invention provides exhaust gas purification catalyst for an internal combustion engine, and exhaust gas purification method using the catalyst. The present invention provides the exhaust gas purification catalyst including a support, a first catalyst layer on an upstream side, a second catalyst layer on a downstream side, and a third catalyst layer. In the exhaust gas purification catalyst, the upstream portion of the third catalyst layer is present on the first catalyst layer, the downstream portion of the third catalyst layer is present on the second catalyst layer, and in the middle portion between the upstream portion and the downstream portion of the third catalyst layer is present between the first catalyst layer and the second catalyst layer.

Abstract: The present invention provides exhaust gas purification catalyst for an internal combustion engine, and exhaust gas purification method using the catalyst. The present invention provides the exhaust gas purification catalyst including a support, a first catalyst layer on an upstream side, a second catalyst layer on a downstream side, and a third catalyst layer. In the exhaust gas purification catalyst, the upstream portion of the third catalyst layer is present on the first catalyst layer, the downstream portion of the third catalyst layer is present on the second catalyst layer, and in the middle portion between the upstream portion and the downstream portion of the third catalyst layer is present between the first catalyst layer and the second catalyst layer.

Abstract: A catalyst for purification of exhaust gas containing a phosphorus compound includes: a lower catalyst layer containing at least one of noble metal provided on a refractory three-dimensional structure; and an upper catalyst layer at an inflow side of exhaust gas and an upper catalyst layer at an outflow side of exhaust gas provided on a surface of the lower catalyst layer. The upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side have different concentrations of noble metal. The catalyst has an intermediate zone with a length of 3 to 23% of the overall length of the refractory three-dimensional structure provided between the upper catalyst layer at the inflow side and the upper catalyst layer at the outflow side. The intermediate zone starts from a position 10 to 38% from an end face of the catalyst at the inflow side of exhaust gas.