Improved performance of NO_x reduction by H_2 and CO over a Pd/Al_2O_3 catalyst at low temperatures under lean-burn conditions

摘要

Selective reduction of NO_x by H_2 and CO in excess O_2 was studied using a Pd/Al_2O_3 catalyst.Incipient wetness impregnation into Al_2O_3 was done using PdCl_2 as the metal precursor.The NO_x conversion profile was maximal at 423 K(up to 95.2% for 250 ppm CO),at which temperature complete oxidation of H2 and CO occurred.There is a very strong synergic effect when both CO and H_2 are simultaneously present in the feed.This catalyst has good selectivity towards N2 and has a window of operation going from 400 to 530 K.