Zero-valent iron (ZVI) activation of persulfate (PS) for oxidation of bentazon in water

Xingya Wei, Naiyun Gao, Changjun Li, Yang Deng, Shiqing Zhou, Lei Li

Research output: Contribution to journalArticle

139 Scopus citations

Abstract

Bentazon (BTZ) in water, a broadly used herbicide in agriculture, is toxic to human beings and has a negative impact on ecosystem. In this study, zero-valent iron (ZVI) activation of persulfate (PS) for the oxidation of BTZ was investigated. More active sulfate radicals produced from the system were principally responsible for the BTZ degradation. The BTZ removal well followed a pseudo-first-order (PFO) kinetics pattern. Key factors affecting the treatment were tested, including ZVI concentration, PS dose, initial BTZ concentration, initial solution pH, temperature and common coexisting ions in water. Under the optimal ZVI (4.477. mM) and PS (0.262. mM) concentrations, 0.021. mM BTZ was totally removed at an initial pH. ≤. 7.Generally, lower BTZ concentration, lower pH and higher temperature favored the treatment. Different coexisting ions exhibited different effects. Al3+, Cl- and NO3- improved the treatment; NH4+, Ca2+, and Mg2+ did not significantly influence the BTZ removal; and, Mn2+, Cu2+, CO32-, HCO3-, PO43-, HPO42- and H2PO4- inhibited the BTZ degradation. Most of BTZ were not mineralized, and instead degraded into three major degradation products including 2,1,3-benzothiadiazin-4(3H)-one-2,2-dioxide (P1, C7H6N2O3S), 2-aminobenzoic acid (anthranilic acid) (P3, C7H7NO2), and 2-amino-2-sulfobenzoic acid (P5, C7H7NO5S). This study demonstrates that ZVI/PS is a viable alternative for controlling BTZ-induced water pollution.

Original languageEnglish
Pages (from-to)660-670
Number of pages11
JournalChemical Engineering Journal
Volume285
DOIs
StatePublished - 1 Feb 2016

Keywords

  • Bentazon
  • Degradation products
  • Degrading mechanism
  • Kinetics
  • Persulfate oxidation
  • Zero-valent iron

Fingerprint Dive into the research topics of 'Zero-valent iron (ZVI) activation of persulfate (PS) for oxidation of bentazon in water'. Together they form a unique fingerprint.

  • Cite this