Electrochemical degradation of malachite green with BDD electrodes: Effect of electrochemical parameters

The dye malachite green (MG) has found extensive use all over the world in the fish farming industry as a fungicide. It has been suspected to be genotoxic and carcinogenic and it has now become a highly controversial compound due to the risks it poses to the consumers of treated fish. In this context electrochemical oxidation of malachite green (MG) has been studied on a one-compartment batch reactor employing a boron-doped diamond (BDD) as anode and a stainless steel as cathode. The effects of several experimental parameters, such as current density, pH initial and supporting electrolyte were investigated. The optimal conditions were determined such as a current intensity of 32 mA cm(-2), strongly acidic pH (pH = 3), and Na2SO4 as a good supporting electrolyte. Under these conditions, a degradation efficiency of 98% was obtained after 60 min of electrolysis and 91% of chemical oxygen demand (COD) removal after 180 min of electrolysis. (C) 2014 Elsevier B.V. All rights reserved.