Establishment of a novel Fenton-like enhanced low-temperature selective catalytic reduction over FeVO4 catalysts

Abstract

Deep NO removal technology for low-temperature flue gas is urgently needed in tail gas purification. This work proposes an efficient Fenton-like enhanced SCR reaction for NO removal. The SCR, Fenton-like, and Fenton-like enhanced SCR reactions were systematically studied with Fe2O3, V2O5, and FeVO4 as catalysts. The results showed that the FeVO4 exhibited an excellent NO removal performance in Fenton-like enhanced SCR reactions at low temperatures. Hydroxyl radicals (•OH) were demonstrated to perform a pivotal role in the NO removal from the radical tests. Moreover, H2O2 vapor inhibited the formation of N2O and improved the N2 selectivity. When the reaction temperature was 175 ℃, and the molar ratio of H2O2 and NO was 6, the NO removal efficiency researched 95.3%, which was 5.5 times higher than that with FeVO4 in SCR reactions. Further, the stability of FeVO4 was verified via the H2-TPR, Raman, FTIR, and SEM characterizations. The XPS results indicated that the regeneration of Fe3+ in Fenton-like enhanced SCR reactions had also positively influenced NO removal. Finally, the rate-determined steps were obtained via kinetic studies so that the mechanism of Fenton-like enhanced SCR reactions were speculated. This study provided a comprehensive view of the structure-activity relationships of FeVO4 catalyst in Fenton-like enhanced SCR reactions and was conducive to promoting potential applications.