The catalytic reduction of NO, with hydrogen and carbon monoxide in the presence of excess oxygen was studied over Pd-based catalysts with various pillared clays (PILC) as the support. The results showed that the Ti-PILC-supported Pd catalyst gave high NO conversions and the highest N-2 product selectivity (compared to known catalysts) at low temperatures. For example, the N-2 selectivity at 140 degreesC was 90% for Pd/Ti-PILC catalyst while that for the Pd/TiO2/Al2O3 catalyst was 50%. The effects of feed gas composition, CO concentration and H2O/SO2 were also studied. (C) 2003 Elsevier B.V. All rights reserved.