TY - JOUR
T1 - Enhanced effect of HAH on citric acid-chelated Fe(II)-catalyzed percarbonate for trichloroethene degradation
AU - Fu, Xiaori
AU - Brusseau, Mark L.
AU - Zang, Xueke
AU - Lu, Shuguang
AU - Zhang, Xiang
AU - Farooq, Usman
AU - Qiu, Zhaofu
AU - Sui, Qian
N1 - Funding Information:
Funding This study was financially supported by grants from the National Natural Science Foundation of China (41373094, 21577033, and 51208199), Natural Science Foundation of Shanghai (16ZR1407200). The contributions of Mark Brusseau were supported by the NIEHS Superfund Research Program (P42 ES04940).
Publisher Copyright:
© 2017, Springer-Verlag GmbH Germany.
PY - 2017/11/1
Y1 - 2017/11/1
N2 - This work demonstrates the impact of hydroxylamine hydrochloride (HAH) addition on enhancing the degradation of trichloroethene (TCE) by the citric acid (CA)-chelated Fe(II)-catalyzed percarbonate (SPC) system. The results of a series of batch-reactor experiments show that TCE removal with HAH addition was increased from approximately 57 to 79% for a CA concentration of 0.1 mM and from 89 to 99.6% for a 0.5 mM concentration. Free-radical probe tests elucidated the existence of hydroxyl radical (HO•) and superoxide anion radical (O2 •-) in both CA/Fe(II)/SPC and HAH/CA/Fe(II)/SPC systems. However, higher removal rates of radical probe compounds were observed in the HAH/CA/Fe(II)/SPC system, indicating that HAH addition enhanced the generation of both free radicals. In addition, increased contribution of O2 •- in the HAH/CA/Fe(II)/SPC system compared to the CA/Fe(II)/SPC system was verified by free-radical scavengers tests. Complete TCE dechlorination was confirmed based on the total mass balance of the released Cl− species. Lower concentrations of formic acid were produced in the later stages of the reaction for the HAH/CA/Fe(II)/SPC system, suggesting that HAH addition favors complete TCE mineralization. Studies of the impact of selected groundwater matrix constituents indicate that TCE removal in the HAH/CA/Fe(II)/SPC system is slightly affected by initial solution pH, with higher removal rates under acidic and near neutral conditions. Although HCO3 − was observed to have an adverse impact on TCE removal for the HAH/CA/Fe(II)/SPC system, the addition of HAH reduced its inhibitory effect compared to the CA/Fe(II)/SPC system. Finally, TCE removal in actual groundwater was much significant with the addition of HAH to the CA/Fe(II)/SPC system. The study results indicate that HAH amendment has potential to enhance effective remediation of TCE-contaminated groundwater.
AB - This work demonstrates the impact of hydroxylamine hydrochloride (HAH) addition on enhancing the degradation of trichloroethene (TCE) by the citric acid (CA)-chelated Fe(II)-catalyzed percarbonate (SPC) system. The results of a series of batch-reactor experiments show that TCE removal with HAH addition was increased from approximately 57 to 79% for a CA concentration of 0.1 mM and from 89 to 99.6% for a 0.5 mM concentration. Free-radical probe tests elucidated the existence of hydroxyl radical (HO•) and superoxide anion radical (O2 •-) in both CA/Fe(II)/SPC and HAH/CA/Fe(II)/SPC systems. However, higher removal rates of radical probe compounds were observed in the HAH/CA/Fe(II)/SPC system, indicating that HAH addition enhanced the generation of both free radicals. In addition, increased contribution of O2 •- in the HAH/CA/Fe(II)/SPC system compared to the CA/Fe(II)/SPC system was verified by free-radical scavengers tests. Complete TCE dechlorination was confirmed based on the total mass balance of the released Cl− species. Lower concentrations of formic acid were produced in the later stages of the reaction for the HAH/CA/Fe(II)/SPC system, suggesting that HAH addition favors complete TCE mineralization. Studies of the impact of selected groundwater matrix constituents indicate that TCE removal in the HAH/CA/Fe(II)/SPC system is slightly affected by initial solution pH, with higher removal rates under acidic and near neutral conditions. Although HCO3 − was observed to have an adverse impact on TCE removal for the HAH/CA/Fe(II)/SPC system, the addition of HAH reduced its inhibitory effect compared to the CA/Fe(II)/SPC system. Finally, TCE removal in actual groundwater was much significant with the addition of HAH to the CA/Fe(II)/SPC system. The study results indicate that HAH amendment has potential to enhance effective remediation of TCE-contaminated groundwater.
KW - Citric acid
KW - Groundwater remediation
KW - Hydroxylamine hydrochloride
KW - ISCO
KW - Sodium percarbonate
KW - Trichloroethene
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U2 - 10.1007/s11356-017-0070-7
DO - 10.1007/s11356-017-0070-7
M3 - Article
C2 - 28889360
AN - SCOPUS:85029000196
SN - 0944-1344
VL - 24
SP - 24318
EP - 24326
JO - Environmental Science and Pollution Research
JF - Environmental Science and Pollution Research
IS - 31
ER -