Application of porous boron-doped diamond electrode towards electrochemical mineralization of triphenylmethane dye

Abstract

The aim of this study is to investigate the electrochemical degradation and decolorization of triphenylmethane dyexylenol orange (XO) on boron-doped diamond (BDD) electrodes. A series of parameters, including electrode materials, current density, initial dye concentration and electrolyte composition, are examined to discuss the effect of these factors in terms of chemical oxygen demand (COD) removal, current efficiency and decolorization rate. Complete decolorization and mineralization of XO could be realized on BDD electrodes while the oxidation is mass transfer controlled, and the degradation progress performs better performance in case of porous BDD electrode comparing with flat BDD electrode. The enhancement of effectiveness is highly correlated to the structure of electrode material, where porous BDD film provides more active sites for hydroxyl radicals. The presence of Cl− in the solution promotes the COD and color removal due to the formation of active chlorine. Porous Ti/BDD electrode presents the excellent potential in electrochemical decolorization and mineralization of triphenylmethane dye.