Enhanced degradation and mineralization of 4-chloro-3-methyl phenol by Zn-CNTs/O3 system

A novel zinc-carbon nanotubes (Zn-CNTs) composite was prepared, characterized and used in O-3 system for the enhanced degradation and mineralization of chlorinated phenol. The Zn-CNTs was characterized by SEM, BET and XRD, and the degradation of 4-chloro-3-methyl phenol (CMP) in aqueous solution was investigated using Zn-CNT5/O-3 system. The experimental results showed that the rate constant of total organic carbon (TOC) removal was 0.29 min-I, much higher than that of only O-3 system (0.059 min(-1)) because Zn-CNTs/O-2 system could generate H2O2 in. situ, the concentration of H2O2 could reach 156.14 mg/L within 60 min at pH 6.0. The high mineralization ratio of CMP by Zn-CNTs/O-3 occurred at wide pH range (3.0-9.0). The increase of Zn-CNTs dosage or gas flow rate contributed to the enhancement of CMP mineralization. The intermediates of CMP degradation were identified and the possible degradation pathway was tentatively proposed. (C) 2017 Elsevier Ltd. All rights reserved.