| 摘要 |
PROBLEM TO BE SOLVED: To provide a catalyst for catalytic reduction of nitrogen oxides with which nitrogen oxides in an exhaust gas can be efficiently reduced without using a large amt. of a reducing agent by selectively reacting, nitrogen oxides with the reducing agent even in the presence of oxygen, especially in the presence of oxygen, sulfur oxides and water in catalytic reduction of nitrogen oxides by using hydrocarbons and oxygen-contg. org. compds. as a reducing agent. SOLUTION: This catalyst for catalytic reduction of nitrogen oxides is prepared by depositing (a) iridium and (b) at least one kind selected from indium and gallium on an oxide carrier and uses hydrocarbons and/or oxygen-contg. org. compds. as a reducing agent. The component (a) is deposited by 0.1 to 10 wt.% calculated as metal, and the component (b) is deposited by 0.1 to 20 wt.% calculated as metals. The oxide carrier consists of titanium oxide, silica, alumina, zirconia or silica alumina. |
