Simultaneous flue gas desulfurization and denitrification were achieved with (OH)-O-center dot radicals from the decomposition of H2O2 over hematite (Fe) as well as hematite supported on alumina (Fe-Al) and anatase( Fe-Ti). Under all conditions, SO2 achieved 100% removal, whereas NOX removal varies with the catalysts. The supporting of Fe over aluminum enhances the catalytic removal of NOX, whereas that of anatase presents negative effect. The NOX removal is determined by the decomposition rate of H2O2 into (OH)-O-center dot radicals over -OH bonded with Fe (Fe-OH). The supporting of Fe over alumina enhances the content of Fe-OH and the points of zero charge (PZC) values, which are beneficial for the production of (OH)-O-center dot radicals. The supporting of Fe over anatase results in the formation of FeOTi, which cannot decompose H2O2 into (OH)-O-center dot radicals. Furthermore, H2O2 tends more to be reacted with TiOH to produce O-2 over Fe-Ti. Finally, the enhancement mechanism of H2O2 decomposition over Fe-based catalysts is speculated. It has a contribution to the correct choice for supports and active ingredients of the catalyst in the future industrial applications. (C) 2014 Elsevier B.V. All rights reserved.