PURPOSE: To improve the heat resistance of an exhaust gas purifying material by depositing at least one kind of oxides of transition metals including the group IIB metals of the periodic table and Sn to a carrier consisting of carbon, depositing also an alkali metal thereto, then binding catalyst particles with calcium aluminate.
CONSTITUTION: After immersing a carrier consisting of carbon, such as graphite, coal, or amorphous carbon, etc. in a soln. of carbonate, nitrate, acetate, or hydroxide, etc. of alkali metal, the carrier is dried naturally or at 100W400°C. Then, the carbon carrier impregnated with said alkali metal is immersed in a soln. contg. acetate, etc. of a transition metal (Ni, Fe, Mn, Co, Cu, Ce, Zn, etc.) including the group IIB metals of the periodic table, and Sn. The product is then dried. Thereafter, calcium aluminate is mixed with the carbon carrier after the treatment as a heat resistant binder. The mixture is mixed further in the wet state with water, and the mixture is molded, dried, and heat-treated to prepare thus an exhaust gas purifying material.