TY - JOUR
T1 - Role of Ferrate(IV) and Ferrate(V) in Activating Ferrate(VI) by Calcium Sulfite for Enhanced Oxidation of Organic Contaminants
AU - Shao, Binbin
AU - Dong, Hongyu
AU - Sun, Bo
AU - Guan, Xiaohong
N1 - Publisher Copyright:
© 2018 American Chemical Society.
PY - 2019/1/15
Y1 - 2019/1/15
N2 - Although the Fe(VI)-sulfite process has shown great potential for the rapid removal of organic contaminants, the major active oxidants (Fe(IV)/Fe(V) versus SO 4 •- / • OH) involved in this process are still under debate. By employing sparingly soluble CaSO 3 as a slow-releasing source of SO 3 2- , this study evaluated the oxidation performance of the Fe(VI)-CaSO 3 process and identified the active oxidants involved in this process. The process exhibited efficient oxidation of a variety of compounds, including antibiotics, pharmaceuticals, and pesticides, at rates that were 6.1-173.7-fold faster than those measured for Fe(VI) alone, depending on pH, CaSO 3 dosage, and the properties of organic contaminants. Many lines of evidence verified that neither SO 4 •- nor • OH was the active species in the Fe(VI)-CaSO 3 process. The accelerating effect of CaSO 3 was ascribed to the direct generation of Fe(IV)/Fe(V) species from the reaction of Fe(VI) with soluble SO 3 2- via one-electron steps as well as the indirect generation of Fe(IV)/Fe(V) species from the self-decay of Fe(VI) and Fe(VI) reaction with H 2 O 2 , which could be catalyzed by uncomplexed Fe(III). Besides, the Fe(VI)-CaSO 3 process exhibited satisfactory removal of organic contaminants in real water, and inorganic anions showed negligible effects on organic contaminant decomposition in this process. Thus, the Fe(VI)-CaSO 3 process with Fe(IV)/Fe(V) as reactive oxidants may be a promising method for abating various micropollutants in water treatment.
AB - Although the Fe(VI)-sulfite process has shown great potential for the rapid removal of organic contaminants, the major active oxidants (Fe(IV)/Fe(V) versus SO 4 •- / • OH) involved in this process are still under debate. By employing sparingly soluble CaSO 3 as a slow-releasing source of SO 3 2- , this study evaluated the oxidation performance of the Fe(VI)-CaSO 3 process and identified the active oxidants involved in this process. The process exhibited efficient oxidation of a variety of compounds, including antibiotics, pharmaceuticals, and pesticides, at rates that were 6.1-173.7-fold faster than those measured for Fe(VI) alone, depending on pH, CaSO 3 dosage, and the properties of organic contaminants. Many lines of evidence verified that neither SO 4 •- nor • OH was the active species in the Fe(VI)-CaSO 3 process. The accelerating effect of CaSO 3 was ascribed to the direct generation of Fe(IV)/Fe(V) species from the reaction of Fe(VI) with soluble SO 3 2- via one-electron steps as well as the indirect generation of Fe(IV)/Fe(V) species from the self-decay of Fe(VI) and Fe(VI) reaction with H 2 O 2 , which could be catalyzed by uncomplexed Fe(III). Besides, the Fe(VI)-CaSO 3 process exhibited satisfactory removal of organic contaminants in real water, and inorganic anions showed negligible effects on organic contaminant decomposition in this process. Thus, the Fe(VI)-CaSO 3 process with Fe(IV)/Fe(V) as reactive oxidants may be a promising method for abating various micropollutants in water treatment.
UR - https://www.scopus.com/pages/publications/85059777903
U2 - 10.1021/acs.est.8b04990
DO - 10.1021/acs.est.8b04990
M3 - 文章
C2 - 30570262
AN - SCOPUS:85059777903
SN - 0013-936X
VL - 53
SP - 894
EP - 902
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 2
ER -