| 摘要 |
PROBLEM TO BE SOLVED: To provide a catalyst capable of excellently removing nitrogen oxides in a strongly oxidized gas mixture at low temperatures. SOLUTION: This catalyst is a catalyst which reduces nitrogen oxides to molecular nitrogen by reducing agents in a medium which is superstoichiometric in oxidizing substances. The composition of the active phase of the catalyst, expressed by weight percentage to a material (excluding a monolith support) baked for four hours at 1000 deg.C, is as follows: 50-99.78% of at least one inorganic refractory oxide, 0.1-20% of at least one rare earth element (A) expressed in a form of its oxide, 0.1-15% of at least one alkaline-earth element (B) in a group IIA, expressed in a form of its oxide, 0.01-5% of at least one platinum group metal (C), and 0.01-10% of at least one silver or gold metal (D) in a noble metal group. |
