Enhanced effect of EDDS and hydroxylamine on Fe(II)-catalyzed SPC system for trichloroethylene degradation

Xiaori Fu, Dionysios D. Dionysiou, Mark L Brusseau, Waqas Qamar Zaman, Xueke Zang, Shuguang Lu, Zhaofu Qiu, Qian Sui

Research output: Contribution to journalArticle

1 Scopus citations

Abstract

This study presents a performance comparison of Fe(II)-catalyzed sodium percarbonate (SPC), Fe(II)-EDDS-catalyzed SPC, and of the innovative hydroxylamine hydrochloride (HA)-Fe(II)-EDDS-catalyzed SPC for the degradation of trichloroethylene (TCE) in water. TCE degradation was greater in the Fe(II)-EDDS-catalyzed SPC system compared to the Fe(II)-catalyzed SPC system, indicating the effectiveness of adding EDDS as an enhancement factor for the removal of TCE. Moreover, TCE degradation was faster in the HA-Fe(II)-EDDS-catalyzed SPC system compared to the Fe(II)-EDDS-catalyzed SPC system, illustrating that HA can play a synergistic role in TCE degradation. Analysis of iron distribution in the three systems demonstrated that EDDS addition maintained iron in soluble form, and that the generation of soluble ferrous from ferric iron was expedited with addition of HA. Studies using nitrobenzene and carbon tetrachloride probes provided insights on the generation of hydroxyl radical (HO) and superoxide anion radical (O2 •−) in the three systems. A gradual increasing contribution of O2 •− to TCE removal in Fe(II)-catalyzed SPC, Fe(II)-EDDS-catalyzed SPC, and HA-Fe(II)-EDDS-catalyzed SPC systems was verified through free-radical scavenger tests. Finally, monitoring of Cl concentrations manifested the complete dechlorination of TCE. A possible mechanism of TCE degradation involving two pathways of HO oxidation and O2 •− reaction was proposed.

Original languageEnglish (US)
Pages (from-to)1-10
Number of pages10
JournalEnvironmental Science and Pollution Research
DOIs
StateAccepted/In press - Mar 25 2018

    Fingerprint

Keywords

  • Fe(II)-EDDS
  • Groundwater remediation
  • Hydroxylamine
  • Sodium percarbonate
  • Trichloroethylene

ASJC Scopus subject areas

  • Environmental Chemistry
  • Pollution
  • Health, Toxicology and Mutagenesis

Cite this