Degradation of 2,4-dichlorophenol by activating persulfate and peroxomonosulfate using micron or nanoscale zero-valent copper

Peng Zhou; Jing Zhang; Yongli Zhang; Gucheng Zhang; Wenshu Li; Chenmo Wei; Juan Liang; Ya Liu; Shihu Shu

doi:10.1016/j.jhazmat.2017.11.023

Degradation of 2,4-dichlorophenol by activating persulfate and peroxomonosulfate using micron or nanoscale zero-valent copper

J Hazard Mater. 2018 Feb 15:344:1209-1219. doi: 10.1016/j.jhazmat.2017.11.023. Epub 2017 Nov 14.

Authors

Peng Zhou¹, Jing Zhang², Yongli Zhang¹, Gucheng Zhang¹, Wenshu Li¹, Chenmo Wei¹, Juan Liang¹, Ya Liu¹, Shihu Shu³

Affiliations

¹ College of Architecture & Environment, Sichuan University, Chengdu 610065, China.
² College of Architecture & Environment, Sichuan University, Chengdu 610065, China. Electronic address: zjing428@163.com.
³ State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.

PMID: 29174048
DOI: 10.1016/j.jhazmat.2017.11.023

Abstract

The ability of persulfate (PS) and peroxymonosulfate (PMS) activated by micron or nanoscale zero-valent copper (ZVC or nZVC) to degrade 2,4-dichlorophenol (2,4-DCP) was quantified under various conditions. Mechanism investigation revealed that PS and PMS accelerated the corrosion of ZVC or nZVC to release Cu⁺ under acidic conditions. The in-situ generated Cu⁺ further decomposed PS or PMS to produce SO₄^- and OH, which then dramatically degraded 2,4-DCP. The k_obs for 2,4-DCP removal followed pseudo-first-order kinetics, k_obs of ZVC/PMS and nZVC/PMS systems were 10∼30 times greater than these in ZVC/PS and nZVC/PS systems. The nZVC/PMS system was most effective to remove 2,4-DCP which even did better than the nZVI/PMS system, with rate constant values ranging from 0.041 to 1.855min^-1. At higher pH ZVC is ineffective, but nZVC can activate PS and PMS to significantly degrade 2,4-DCP at pH up to 7.3. The 2,4-DCP degradation pathway was found to involve dechloridation, dehydrogenation, hydroxylation, ring open and mineralization. 56.7% and 45.3% of TOC removals were respectively obtained in the ZVC/PMS and nZVC/PMS systems within 120min. This study helps to comprehend the application of zero-valent metals in reactive radicals-based oxidation processes and the reactivity of Cu⁺ as an activator of PS and PMS.

Keywords: Hydroxyl radical; Peroxymonosulfate; Persulfate; Sulfate radical; Zero-velant copper.