Carbonate-Promoted Catalytic Activity of Potassium Cations for Soot Combustion by Gaseous Oxygen

The possible mechanism of soot combustion catalyzed by potassium carbonate loaded on aluminosilicate was elucidated to understand the surface reaction in solid-solid-gas triphasic catalysis. Potassium species on aluminosilicate showed high catalytic performance for the oxidation of carbon black by gaseous oxygen. Aluminosilicate helped in stabilizing the alkali cation on the surface. The carbonate ion played a critical role in enhancing the catalytic performance by acting as a supplier of active electrons to gaseous oxygen. To the best of our knowledge, this is the first report on the essential role of carbonate on the catalytic activity of an alkali cation for an oxidation reaction, although carbonate (carbon dioxide) is widely recognized to hinder the catalytic performance of the alkali compound for base-catalyzed reactions.