Electrocatalytic oxidation of phenol from wastewater using
Ti/SnO2–Sb2O4 electrode: chemical reaction pathway study
- Publication date
- Publisher
Abstract
Abstract In this study, a titanium plate was impregnated with
SnO2 and Sb (Ti/SnO2–Sb2O4) for the electrocatalytic removal
of phenol from wastewater, and the chemical degradation
pathway was presented. The effects of various parameters
such as pH, current density, supporting electrolyte, and initial
phenol concentration were studied. At optimum conditions, it
was found that phenol was quickly oxidized into benzoquinone
because of the formation of various strong radicals during
electrolysis by the Ti/SnO2–Sb2O4 anode from 100 to
<1 mg/L over 1 h. The results of GC/MS analysis showed
the presence of some esters of organic acid such as oxalic acid
and formic acid. HPLC analysis showed only trace amounts of
benzoquinone remaining in the solution. The efficiency of
TOC removal at the Ti/SnO2–Sb2O4 anode surface showed a
degradation rate of 49 % over 2 h. Results showed that the
molecular oxygen potential at the electrode was 1.7 V. The
phenol removal mechanism at the surface of the Ti/SnO2–
Sb2O4 anode was influenced by the pH. Under acidic conditions,
the mechanism of electron transfer occurred directly,
whereas under alkaline conditions, the mechanism can be indirect.
This research shows that the proposed electrolyte can
significantly influence the efficiency of phenol removal. It can
be concluded that the treatment using an appropriate Ti/SnO2–
Sb2O4 electrode surface can result in the rapid oxidation of
organic pollutants