Removal of NO from flue gas by wet scrubbing with NaClO2/(NH2)2CO solutions

Integrative process of preoxidation and absorption for simultaneous removal of SO2, NO and Hg0

“…(12)) was also contributed to the oxidation reactions [15,23,26,28,35,44]. Moreover, ClO 2 could generate Cl Á and Cl 2 via the reactions of 15 to 17, which had been demonstrated previously [15,28,44]. Therefore, the secondary oxidants such as ClO 2 , Cl Å and Cl 2 partly contributed to the oxidation of SO 2 , NO and Hg 0 (Eqs.…”

“…It has been reported in the literature that the solution pH has a significant effect on the oxidation potential of NaClO 2 [23][24][25][26][27][28][29]. Therefore, the dependence of simultaneous removal on ACO pH was investigated.…”

“…Zhao et al [15] who found that a pH of 5.5 was suitable for NaClO/NaClO 2 oxidizing NO in a bubble reactor. Wei et al [28] revealed that when the initial pH value of the NaClO 2 /CO(NH 2 ) 2 solution changed from 7.05 to 10.51, NO removal efficiency remained approximately 97.3% in a wet scrubber. Moreover, UV-Vis was employed to determine the ClO 2 generation.…”

“…Based on the related literature references [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39]44], we inferred that the main functional oxidants in the reaction system were ClO 2 À , ClO 2 , Cl 2 , ClÁ and Br 2 . From the electrochemistry, the standard electrode potentials of ClO 2 À /Cl À (1.599 V), ClO 2 /Cl À (1.511 V), Cl 2 /Cl À (1.396 V) and Br 2 /Br À (1.09 V) are higher than those of Hg 2+ /Hg 0 (0.796V), SO 4 2À /H 2 SO 3 (0.172 V), SO 4 2À /SO 2 (0.158V), NO 2 /NO (1.049 V), NO 3 À /NO (0.957 V), NO 2 À /NO (-0.460V) and NO 3 À /NO 2 À (0.835 V), indicating that the oxidation of SO 2 , NO and Hg 0 by vaporized ACO can occur.…”

Simultaneous removal of SO2, NO and Hg0 by wet scrubbing using urea + KMnO4 solution

“…Ammonium sulfate can be recycled, and gasses can be directly released into the atmosphere. Some researchers had investigated the NO removal characteristics by wet scrubbing with urea solutions [26,27], but there is limited information on the simultaneous removal of Hg 0 , SO 2 and NO using urea + KMnO 4 solution in the literatures. In this study, a sequence of experiments was carried out in order to evaluate the influences of different operational parameters on Hg 0 , SO 2 and NO removal efficiencies in a bubble column reactor, and the optimal experimental conditions were established, meanwhile the mechanism of the reaction in the process was also hypothesized.…”