Integrative Process for Simultaneous Removal of SO2 and NO Utilizing a Vaporized H2O2/Na2S2O8

A novel integrative process for simultaneous removal of SO2 and NO from coal-fired flue gas was designed, in which, SO2 and NO were initially oxidized by a vaporized complex oxidant composed of hydrogen peroxide (H2O2) and sodium persulfate (Na2S2O8) (HN solution) and then absorbed by the Ca(OH)(2) that followed. The effects of various reaction factors on the simultaneous removal were investigated, such as the concentration of Na2S2O8, the transition metal additives, the HN pH, the adding rate of HN, the residence time of flue gas, the reaction temperature, and the concentrations of coexistence gases O-2, SO2, NO, and CO2. Under the optimal conditions, the simultaneous removal efficiencies of 98.9% for SO2 and 79.6% for NO were obtained. The reaction mechanism was speculated based on the characterization of removal products by scanning electron microscopy and X-ray diffraction and related literature references. Meanwhile, the macrokinetics of desulfurization and denitrification were also calculated.