Patent ID: 7913486

Claim:
An exhaust emission control device with a NO x -occlusion reduction catalyst incorporated in an exhaust passage so as to reduce and purify NO x , comprising: fuel reforming means arranged in the exhaust passage upstream of the NO x -occlusion reduction catalyst for decomposing fuel into H 2 and CO; plasma generating means arranged in the exhaust passage upstream of the fuel reforming means for oxidizing NO into NO 2 ; and a controller for controlling said fuel reforming means and said plasma generating means, wherein said controller controls said plasma generating means to oxidize NO into NO 2 for acceleration of NO x -occlusion by the NO x -occlusion reduction catalyst when exhaust/fuel ratio is lean, controls said fuel reforming means to decompose the fuel into H 2 and CO for reduction of NO x in the NO x -occlusion reduction catalyst when air/fuel ratio is fuel-rich and controls said fuel reforming means to feed the fuel without decomposition to instantly make the fuel denser when exhaust temperature is sufficiently high.