Development of a rapid ageing technique for modern methane combustion catalysts in the laboratory: Why does SO2 concentration play an essential role?

In pursuance to decrease emissions of transportation sector, the durability and longevity of modern catalysts has become a topical issue. Understanding the deactivation of catalysts is especially urgent. Our aim in this study was to clarify the roles of reaction temperature and SO2 concentration in methane combustion catalyst poisoning. Information about this process can help the research community perform more realistic laboratory simulations and provide new insights for catalyst development. With the collected experimental data, the likelihood that poisoning would be influenced by different sulphur species and mechanisms was evaluated. Our results suggested that both reaction temperature and SO2 concentration influenced the stability of the resulting sulphates. Low SO2 concentrations lead to formation of stabler sulphates and lower total amount of sulphur in the catalyst. In turn, high SO2 concentrations formed less stable sulphates but accumulated more sulphur. Lesser stability was attributed to formation of Al-2(SO4)(3) through spillover.