Search

A series of MnFe catalysts were prepared by hydrothermal synthesis combined with heat treatment at different temperatures. The characterizations demonstrated that MnFe-120 with both surface -OH and -NO 3 , MnFe-175 with surface -OH, MnFe-300 containing neither surface -OH nor -NO 3 , and MnFe-300-NO 3 containing surface -NO 3 were gained by drying or calcination and impregnation. The activity evaluation showed that the order of catalytic activity was MnFe-120 > MnFe-175 > MnFe-300-NO 3 > MnFe-300. Further, characterizations and experiment results revealed that O 3 adsorbed on the surface of the catalyst can interact with surface -OH and generated hydroxyl radicals (·OH). The presence of surface -NO 3 provided more Lewis acid sites, thereby promoting H 2 O adsorption and conversion to the surface -OH, which supplemented the surface -OH consumed by the interaction with O 3. It was deduced that the coexistence of surface -OH and -NO 3 improved the production of·OH, which synergistically promoted the catalytic ozonation of toluene. [Display omitted] • A series of MnFe catalysts with different amounts of surface -OH and -NO 3 were prepared. • MnFe catalyst containing both surface -OH and -NO 3 had a optimal catalytic ozonation performance for toluene. • O 3 adsorbed on the surface -OH sites and hydroxyl radicals (·OH) to oxidize toluene was produced. • H 2 O adsorbed on the surface -NO 3 sites and was converted to the surface -OH, which supplemented the surface -OH consumed. • The synergistic effect of surface -OH and -NO 3 increased the amount of·OH production. [ABSTRACT FROM AUTHOR]