Abstract:

The gas file, surface file and thermal file of LNT in Chemkin were rewritten, and the adsorption model of lean NO_x trap (LNT) , which included two kinds of adsorption paths, was developed to investigate the influence of CO₂ concentration and temperature of lean burn gasoline exhaust on the adsorption path from
150 to 400 ℃ . The main research results show that the presence of CO2 has influence on the both paths, and CO₂ has more inhibition on nitrite path than nitrate path. With the concentration of CO₂ increasing, the effect of inhibition weakens. The influence of exhaust temperature on both of the paths is more significant. During low temperature 150-200 ℃ , nitrite path is major path because of the inactivation of nitrite evolution and NO oxidation. While at the high temperatures of 300 ℃ and 400 ℃ , two paths have similar occupancy

Key words: lean burn gasoline, lean NO_x trap (LNT), carbon dioxide (CO₂), temperature, adsorption path.