TY - JOUR
T1 - Both Fe(IV) and Radicals Are Active Oxidants in the Fe(II)/Peroxydisulfate Process
AU - Dong, Hongyu
AU - Li, Yang
AU - Wang, Shuchang
AU - Liu, Weifan
AU - Zhou, Gongming
AU - Xie, Yifan
AU - Guan, Xiaohong
N1 - Publisher Copyright:
Copyright © 2020 American Chemical Society.
PY - 2020/3/10
Y1 - 2020/3/10
N2 - The question of whether Fe(IV) or SO4 â - is the dominant intermediate in the Fe(II)-Activated peroxydisulfate process [Fe(II)/PDS process] remains unanswered. In this study, besides Fe(IV), SO4 â - and HOâ were shown to be produced in the Fe(II)/PDS process by using multiple probes [dimethyl sulfoxide, methyl phenyl sulfoxide, p-nitrobenzoic acid (p-NBA), and benzoic acid (BA)]. The removal of p-NBA and BA and the influence of BA on the yield of methyl phenyl sulfone (PMSO2) indicated that the major oxidizing intermediate changed from Fe(IV) to SO4 â -/HOâ with an increase in the PDS/Fe(II) molar ratio at pH 3.0. Fe(IV), SO4 â -, and HOâ were all involved in this process at pH 3.0-6.5, but their available amounts that contributed to abating organic contaminants decreased with an increase in pH considering the influence of pH on the generation of PMSO2 and p-hydroxybenzoic acid. Furthermore, Fe(IV), SO4 â -, and HOâ contributed differently to abating different organic contaminants because of the different reactivities of these oxidizing oxidants toward different organic contaminants. Overall, this study demonstrates that multiple oxidizing species [Fe(IV), SO4 â -, and HOâ ] are generated in the Fe(II)/PDS process, which was significant for the application of this process and understanding the mechanisms of Fe(II)-Activated peroxide processes.
AB - The question of whether Fe(IV) or SO4 â - is the dominant intermediate in the Fe(II)-Activated peroxydisulfate process [Fe(II)/PDS process] remains unanswered. In this study, besides Fe(IV), SO4 â - and HOâ were shown to be produced in the Fe(II)/PDS process by using multiple probes [dimethyl sulfoxide, methyl phenyl sulfoxide, p-nitrobenzoic acid (p-NBA), and benzoic acid (BA)]. The removal of p-NBA and BA and the influence of BA on the yield of methyl phenyl sulfone (PMSO2) indicated that the major oxidizing intermediate changed from Fe(IV) to SO4 â -/HOâ with an increase in the PDS/Fe(II) molar ratio at pH 3.0. Fe(IV), SO4 â -, and HOâ were all involved in this process at pH 3.0-6.5, but their available amounts that contributed to abating organic contaminants decreased with an increase in pH considering the influence of pH on the generation of PMSO2 and p-hydroxybenzoic acid. Furthermore, Fe(IV), SO4 â -, and HOâ contributed differently to abating different organic contaminants because of the different reactivities of these oxidizing oxidants toward different organic contaminants. Overall, this study demonstrates that multiple oxidizing species [Fe(IV), SO4 â -, and HOâ ] are generated in the Fe(II)/PDS process, which was significant for the application of this process and understanding the mechanisms of Fe(II)-Activated peroxide processes.
UR - https://www.scopus.com/pages/publications/85081001538
U2 - 10.1021/acs.estlett.0c00025
DO - 10.1021/acs.estlett.0c00025
M3 - 文章
AN - SCOPUS:85081001538
SN - 2328-8930
VL - 7
SP - 219
EP - 224
JO - Environmental Science and Technology Letters
JF - Environmental Science and Technology Letters
IS - 3
ER -