摘要 |
The invention provides a catalyst for catalytically reducing nitrogen oxides in diesel engine exhaust gas by use of unburnt carbon contained in the diesel engine exhaust gas as a reducing agent, the catalyst comprising: (a) an acid zeolite, or (b) an alkali metal- and/or alkaline earth metal-containing zeolite, or (c) a rare earth metal-containing zeolite, or (d) a zeolite containing at least one transition metal selected from Fe, Co, Ni and Cu.
|