| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for cleaning exhaust by which NOx and PM can be continuously self-removed under ordinary burning conditions without requiring specified control and to provide an exhaust cleaning catalyst and an apparatus for cleaning exhaust. SOLUTION: In the method for cleaning exhaust, PM particles and NOx in exhaust are removed by converting the PM particles to HC by a reaction represented by the formula mC+nH2 O→H2n Cm +n/2.O2 . The apparatus for cleaning exhaust has a filter obtained by carrying a noble metal and fine oxide particles of <=1 μm average particle diameter on the inner walls of pores in a monolithic filer and disposed in an exhaust flue. In the method for cleaning exhaust, hydrogen generation reactions represented by the formulae C+H2 O→H2 +CO and C+2H2 O→2H2 +CO2 are carried out at <=500 deg.C exhaust temperature. The exhaust cleaning catalyst contains an H2 generation catalyst and an NOx removal catalyst, the H2 generation catalyst contains Rh-carrying porous particles and metals such as Fe, Co, Mn and Ni, and these metals are contained at a ratio of 0.1-10 when Rh is represented by 1. |
