| 摘要 |
<p>PURPOSE:To obtain a catalyst for purification of exhaust gas contg. NOx, CO and hydrocarbon. CONSTITUTION:Iridium is carried on a crystalline silicate having an X-ray diffraction pattern represented by the chemical formula (1+ or -0.4)R2O.[aBi2O3.bLa2 O3.cCe2O3.dM2O3].ySiO2 when the silicate is expressed in terms of the molar ratio among oxides in a dehydrated state. In the formula, R is ions of Na and/or H, M is ions of one or more kinds of group VIII: metals or an ion of Ti, V, Cr, Nb, Sb or Al, a+b+c+d=1, a>=0, b>=0, c>=0, d>=0, a+b+c>0 and y>=12. The objective catalyst for treatment of exhaust gas is obtd.</p> |
