| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust gas cleaning system which generates more hydrogen and dramatically improves an NOx purification ratio in a low temperature range. <P>SOLUTION: The exhaust gas cleaning system comprises a CO removing catalyst installed in an exhaust passage of an internal combustion engine, an NOx adsorbing purification catalyst installed in the downstream side of the above catalyst and a water supply means. The CO removing catalyst at least removes CO and generates hydrogen, or allows the hydrogen included in the exhaust gas to permeate. The NOx adsorbing purification catalyst adsorbs NOx when the exhaust gas is lean and eliminates the adsorbed NOx when in stoichiometric or rich conditions. The water supply means increases the water supply amount according to the increase of a rich level and the decrease of an exhaust gas temperature. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
