Simultaneous removal of NOX and SO2 with H2O2 over Fe based catalysts at low temperature

Abstract

Simultaneous flue gas desulfurization and denitrification are achieved with ˙OH radicals generated from H₂O₂ catalyzed by Fe based transition metal (Fe, Fe–Al, Fe–Ti, Fe–Si) oxides in the duct, followed by purification with ammonia-based glass made washing tower. The main recovered products are the ammonia nitrate and sulfate, which are important fertilizers. In this oxidation-removal process, 100% SO₂ and 74% NO_X removal efficiencies are achieved at the simulated flue gas temperature of 120–180 °C under the applied conditions with a space velocity of 36 000 h⁻¹. The experimental results show that the enhancement of Lewis acid benefits the generation of O₂ without ˙OH radical production. The increase of Fe³⁺ bonded with hydroxyl group and points of zero charge value are beneficial to produce ˙OH radicals, thus improving the NO_X removal efficiency.