| 摘要 |
PROBLEM TO BE SOLVED: To obtain a catalyst having a high dispersibility and a high NOx- occluding capacity when an alkali metal, an alkali earth metal or a rare earth metal is carried on a catalytist carrier. SOLUTION: This catalytic metal colloid is used when a process A for carrying an alkali metal, an alkali earth metal or a rare earth metal, and a process B for carrying another chelated catalytic metal are executed as separate processes. When one kind or at least two kinds of catalytic metals to be used in the process B are made colloidal by chelating bond in this case, a certain specific polymer chelating agent is used. |
