Behavior of some deep oxidation catalysts under extreme conditions. 1. Comparison of resistance to thermal shock and SO2 poisoning Original Research Article

The activity of catalysts before and after heat treatment up to 950°C was measured in model reactions of methane and butane deep oxidation. The poison stability was investigated by examining the catalysts in deep oxidation of methane (1 vol% in air) in the presence of SO2 (0.05 vol%). The alumina-manganese oxide catalyst was found to be the most resistant to overheating. It lowered the activity in deep methane oxidation ∼2.5 times only after calcination at 950°C for 800 h. The more poison stable samples were found to be alumina-palladium and perovskite (on the base of LaMnO3) catalysts. The activity of more thermostable alumina-manganese oxide catalyst is lowered up to zero activity in deep oxidation of methane at 500°C. But at reaction temperature 700°C the catalyst is sufficiently stable to poisoning.