Electro-assisted heterogeneous activation of persulfate by Fe/SBA-15 for the degradation of Orange II

Chun Cai; Zhuoyue Zhang; Hui Zhang

doi:10.1016/j.jhazmat.2016.04.007

Electro-assisted heterogeneous activation of persulfate by Fe/SBA-15 for the degradation of Orange II

J Hazard Mater. 2016 Aug 5:313:209-18. doi: 10.1016/j.jhazmat.2016.04.007. Epub 2016 Apr 6.

Authors

Chun Cai¹, Zhuoyue Zhang², Hui Zhang³

Affiliations

¹ Department of Environmental Engineering, Wuhan University, Wuhan 430079, China; Shenzhen Research Institute of Wuhan University, Shenzhen 518057, China.
² Department of Environmental Engineering, Wuhan University, Wuhan 430079, China.
³ Department of Environmental Engineering, Wuhan University, Wuhan 430079, China; Shenzhen Research Institute of Wuhan University, Shenzhen 518057, China. Electronic address: eeng@whu.edu.cn.

PMID: 27124213
DOI: 10.1016/j.jhazmat.2016.04.007

Abstract

The removal of Orange II by activation of persulfate (S2O8(2-), PS) using synthesized Fe/SBA-15 in the electrochemical (EC) enhanced process was reported in this study. The reaction rate constants, degradation mechanism, catalyst stability, and evolution of mineralization and toxicity were detailed investigated. On the basis of radical scavenger results, both the sulfate radicals (SO4(-)) and hydroxyl radicals (OH) were responsible for the degradation of Orange II. A possible pathway is suggested to describe the degradation of Orange II according to the degradation intermediates identified. The results showed that the Fe/SBA-15 catalyst maintained strong reusability and stability with a low level of iron leaching. In addition, favorable mineralization efficiency in terms of COD removal efficiency (75.4%) and TOC removal efficiency (46.3%) was obtained when the reaction time was prolonged to 24h. The toxicity experiments implied that the toxicity of the treated solution ascended at the first 30min but then dropped to almost zero eventually. This study provides a proof-of-concept that can be applied widely for the PS remediation of contaminated water.

Keywords: Electrochemical; Fe/SBA-15; Persulfate; Sulfate radicals; Toxicity.

Publication types

Research Support, Non-U.S. Gov't