| 摘要 |
PURPOSE:To minimize the sintering of catalyst metal even when used for a long time at a high temperatures and to maintain the catalytic activity for a long period of time by forming silicate particles containing metal into a cylindrical shape in an exhaust gas purifying catalyst in which a catalyst metal is supported on silicate particles containing a metal. CONSTITUTION:In the exhaust gas purifying catalyst in which a catalyst metal is supported on crystalline silicate particles 1 containing a metal, the silicate particles 1 are formed into a cylindrical shape. In this way, the silicate particles 1, even when, for example, supported on a honeycomb carried or pelletized to be packed closely, have greater porosity and a smaller contact area than the particles of a spherical shape. Consequently, even between the closest particles, the accessibility of the catalyst metal supported on the particles decreases so that chances of the mutual contact of the catalyst metal decrease even when the catalyst metal moves on the surface of the particles by heat. In order words, the probability of sintering of the catalyst metal laid across more than one particle 1 is reduced. |
