Enhanced activity of Ba-doped Ir/SiO2 catalyst for NO reduction with CO in the presence of O2 and SO2

The effect of metal additives on the catalytic performance of Ir/SiO2 catalyst for the selective reduction of NO with CO in the presence of O2 and SO2 was investigated. Among the 19 additives tested here, the addition of barium was the most effective to enhance the activity of Ir/SiO2 at low temperature and low SO2 concentration. Catalyst characterization suggested that barium prevents catalyst deactivation as an oxidation-retardant for the active Ir metal supported on SiO2.