A facile preparation of hausmannite as a high-performance catalyst for toluene combustion

Mesoporous transition metal oxide catalysts are well-used in the elimination of volatile organic com-pounds.In this study,we developed an efficient method for the preparation of mesoporous-Mn3O4(m-Mn3O4)without the use of templates or surfactants.In this method,KCl protects oxygen defects on the surface of fresh Mn3O4 crystallites.m-Mn3O4 shows higher ameliorative catalytic activity than bulk-Mn3O4(b-Mn3O4)and calcined-Mn3O4(c-Mn3O4),achieving toluene catalytic oxidation of T1o and T90(the temperature at a conversion rate of about 10％and 90％)at 191℃and 230℃,respectively(WHSV=40,000 ml·g-1·h-1).Based on various characterizations,the prepared m-Mn3O4 has large speci-fic surface area and abundant oxygen defects,and thus can provide more surface active sites,which give it superior toluene combustion activity.