Oxidative absorption of NO by sodium persulfate coupled with Fe²⁺, Fe₃O₄, and H₂O₂

Abstract

The oxidative absorption of nitric oxide (NO) by sodium persulfate (Na2S2O8) coupled with Fe2+, Fe3O4, and H2O2 was investigated in a bubble column reactor. Moreover, the effect of temperature on NO removal has been studied. At high temperatures, Fe2+ and Fe3O4 could effectively activate persulfate to form sulfate radicals, leading to high removal efficiency of NO. About 62% and 86% of NO were removed at 75 and 90°C, respectively. Also, the optimum Fe2+ concentration for 0.2 mol L−1 persulfate was 1.0 mmol L−1 at 75°C, under which the removal efficiency of NO was observed to be 89%. However, beyond 1.0 mmol L−1 Fe2+, the increase in Fe2+concentration was unfavorable to NO removal due to the scavenging of radicals by the excess Fe2+. Additionally, the presence of 2.85 mmol L−1 Fe3O4 increased the NO removal efficiency by 11% compared to that obtained in the absence of Fe3O4. It was proposed that activation ability of Fe3O4 to persulfate was attributed to Fe2+ on the Fe3O4 surface. Moreover, the addition of H2O2 led to the increase of the NO removal for some time, but followed by a drop because of the depletion of H2O2. It was suggested that H2O2 served as an oxidant rather than an activator of persulfate. © 2014 American Institute of Chemical Engineers Environ Prog, 2014 © 2014 American Institute of Chemical Engineers Environ Prog, 34: 117–124, 2015

Cation ratio and oxygen defects for engineering the magnetic transition of monodisperse nonstoichiometric zinc ferrite nanoparticles

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Removal of NO from flue gas using heat-activated ammonium persulfate aqueous solution in a bubbling reactor

“…It was observed that the NO removal efficiency decreased from 42% to 31% with the SO 2 concentration increased from 0 to 4000 ppm. The additive SO 2 could react with water via reactions (19) and (20) and subsequently, oxidation reaction of sulte ion or bisulte ion consumed SO 4 c À /cOH and produced SO 3 c À via reactions ( 21)- (23). The SO 3 c À easily reacted with water via reaction (24), producing SO 4…”

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Removal of nitric oxide in a microporous tube‐in‐tube microchannel reactor by ferrous chelate solution

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