US EPA

3226337 

Journal Article 

Study on the removal of nitric oxide (NO) by dual oxidant (H2O2/S2O82-) system 

Wang, Z; Wang, Z; Ye, Yin; Chen, Na; Li, H 

2016 

Yes 

Chemical Engineering Science
ISSN: 0009-2509 

145 

133-140 

10.1016/j.ces.2016.02.018 

WOS:000373407400013 

In this paper, the removal of NO with dual oxidant (H2O2/S2O82-) system was studied in a bubble column reactor. The contrast experiment for a different system showed that the combination of Na2S2O8 and H2O2 had a significant synergistic effect on NO removal. The effects of Na2S2O8 concentration (0.020.2 mol/L), H2O2 concentration (0.25-2 %), molar ratio of H2O2 to Na2S2O8 (0.3:0.2-0.3:0.02 mol/mol), reaction temperature (21-70 degrees C) and initial pH value (1-11) on the removal efficiency of NO were investigated. The NO removal efficiency increased with the increase of Na2S2O8 and H2O2 concentrations. However, above 1 % hydrogen peroxide and 0.1 mol/L persulfate, the rate of increase in NO removal efficiency gradually slowed down. The optimal molar ratio of H2O2 to Na2S2O8 is 0.3:0.1 mol/mol. The optimum temperature for the thermal activation of dual oxidant (H2O2/S2O82-) system was 50 degrees C. The highest NO removal efficiency (82 %) was obtained at pH 11. The final ionic products were analyzed by ion chromatography. Combined with N material balance, NO3- was the final ionic product in spent reaction solution. A preliminary reaction mechanism for the removal of NO in dual oxidant (H2O2/S2O82-) solution was deduced. This dual oxidant (H2O2/S2O82-) system proved to be a promising reagent for wet denitration. (C) 2016 Elsevier Ltd. All rights reserved. 

Nitric oxide; Oxidation; Sulfate radicals; Hydroxyl radicals; Wet scrubbing