A catalyst for purifying exhaust gas of an internal combustion engine and its manufacturing method

文件类型：PDF文档
文件大小：61K
PROBLEM TO BE SOLVED : To produce a catalyst which is provided with a catalyst carrier having a high oxygen absorbing/releasing performance. SOLUTION : The catalyst having the high oxygen absorbing/releasing performance can be obtained by using, as the catalyst carrier, A2O2SO4(wherein A is a rare-earth element) obtained by firing a raw material being a sulfate of the rare-earth element in air at ≥800°C to decompose a part of the sulfate group. The catalyst carrier shown by the formula A2O2SO4changes into A2O2S in a reducing atmosphere of high temperature (≥ about 800°C) while releasing the absorbed oxygen to the outside. The A2O2S changes into the A2O2SO4in an oxidizing atmosphere while absorbing oxygen. COPYRIGHT : (C)2005, JPO&NCIPI