La0.8Cu0.2MnO3 and La0.8Sr0.2MnO3 perovskite catalysts were prepared by the co-precipitation method. The resistance of these catalysts to sulfur poisoning
was tested via catalytic combustion of toluene. The results show that the perovskite catalysts were poisoned in the presence
of SO2. In the presence of dodecyl mercaptan (C12H25SH), La0.8Sr0.2MnO3 exhibits better resistance to sulfur poisoning than La0.8Cu0.2MnO3. It was determined that the SO2 deactivation is due to the formation of CuSO4 on the catalyst surface.