Abstract: Montmorillonite was pillared by multi-oligomeric hydroxyl cations to synthesize Al-Ce-PILC (PILC[CD1]pillared interlayer clay), which was modified by SO2-4 and then was used as a catalyst support to prepare the Cu/Al-Ce-PILC catalyst by impregnation. The influence of pretreatment atmosphere, concentration of O2 and C3H6, space velocity, water vapor, and SO2 on the conversion of NO and C3H6 over Cu/Al-Ce-PILC was investigated. The results showed that both Cu+and Cu2+ species were observed on Cu/Al-Ce-PILC pretreated in He, while only Cu+ existed after being pretreated in H2, and the maximum NO conversion was enhanced from 23% to 56%. Proper concentration of O2 and C3H6 promoted the reduction of NO to N2, and the formation of coke was distinctly suppressed by excess oxygen. NO conversion decreased with increasing space velocity. The presence of 10% water vapor in the feed restrained the selective catalytic reduction (SCR) of NO, the temperature for the maximum conversion increased, and the maximum conversion of NO and C3H6 decreased by 13% and 5%, respectively. Compared with Cu-ZSM-5, Cu/Al-Ce-PILC showed better resistance to water vapor owing to the hydrophobic nature of the oxide pillar surface. SO2 greatly inhibited the SCR activity of Cu/Al-Ce-PILC at low temperature and slightly promoted it at high temperature.

Key words: copper, aluminum, cerium, pillared interlayed clay, nitrogen oxide, selective catalytic reduction, propylene