| 摘要 |
PURPOSE:To suppress the reduction of specific surface area and activity due to sintering even at high temp. and to improve heat resistance by mixing oxides, carbonates, etc., of corresponding metals, pulverizing and firing the resultant mixture. CONSTITUTION:Oxides, carbonates, etc., of corresponding metals are mixed in a prescribed stoichiometric ratio, a dispersive medium is added and they are mixed, pulverized, dried and fired at 800-1,350 deg.C for 5-10hr in the air to obtain the objective heat resistant perovskite type multiple oxide represented by the formula AB1-xCxO3 (where A is a rare earth element and/or an alkaline earth metal, B is at least one selected from among Mn, Co and Cr, C is Ta and or Nb and 0.1<x<1.0). |
