Original Articles: 2012 Vol: 4 Issue: 7
Electrochemical degradation of difenoconazole on BDD electrodes
Abstract
The electrochemical oxidation of fungicide difenoco nazole ( Cis-trans-3-chloro-4-[4-methyl-2-(1H-1,2,4 -triazol-1- ylmethyl)-1,3-dioxlan-2-yl]phenyl 4-chlorophenyleth er ), one kind of triazole fungicides is potential ly dangerous and biorefractory, was studied by galvanostatic ele ctrolysis using boron-doped diamond (BDD) as anode. The influence of several operating parameters, such as applied current density, initial difenoconazole con centration, temperature, supporting electrolyte, and initial pH value, was investigated. GC and chemical oxygen de mand measurements were conducted to study the reaction k inetics of pesticide mineralization. The experiment al results showed that the electrochemical process was suitabl e for almost completely removing COD, due to the pr oduction of hydroxyl radicals on the diamond surface. In par ticular, the COD removal follows a pseudo first-ord er kinetics and the apparent rate constant increased with curre nt density and supporting electrolyte NaCl, while i t is almost unaffected by temperature, and pH. Under optimal ex perimental conditions of temperature (T=25 °C) and current density (i.e. 80 mA/ cm 2 ), 73% of COD was removed in 3 h electrolysis.