| 摘要 |
PROBLEM TO BE SOLVED: To promote activation of noble metals and to improve low temp. activity from the initial stage after long-term use by using an alumina-based multiple oxide containing at least one kind of lanthanum, nickel and cobalt in a specified compsn. ratio as the carrier base of noble metals. SOLUTION: This catalyst for purification of exhaust gas consists of an alumina multiple oxide containing at least one kind selected from lanthanum, nickel and cobalt. The alumina-based multiple oxide is prepared by dispersing or dissolving fine particles of alumina hydrate colloid (alumina sol), a water-soluble salt of at least one kind of element selected from cobalt and nickel, and a water-soluble salt of lanthanum in water, adding at least one kind of aq. soln. selected from ammonia water, aluminum carbonate, ammonium hydrogen carbonate, ammonium sulfate and ammonium hydrogen sulfate, then removing water, drying and calcining. |
