Electrochimica Acta, Vol.52, No.9, 3242-3249, 2007
Electrochemical degradation of 17 beta-estradiol (E2) at boron-doped diamond (Si/BDD) thin film electrode
Electrochemical degradation of aqueous solutions containing 17 beta-estradiol (E2), concentrations range of 250-750 mu g dm(-3), has been extensively studied using boron-doped diamond (131313) anode with a working solution volume of 250 ml under galvanostatic control. Cyclic voltammetric experiments were performed to examine the redox response of E2 as a function of cycle number. The effect of operating variables such as initial concentration of E2, applied current density, supporting medium (Na2SO4, NaNO3, and NaCl) and initial pH of the electrolyte (pH 2-10) were systematically examined and discussed. Electrolysis at high anodic potential causes complex oxidation of E2 that leads to form the final sole product as CO2. A pseudo first-order kinetics for E2 decay was found against varying applied current density. Also, kinetic analysis suggests that electrooxidation reaction of E2 undergo the control of applied current density. It was observed that electrolyte pH and supporting medium have a vital role on E2 degradation. From a comparison study with other anode materials such as platinum (Pt) and glassy carbon (GC), the superiority of the BDD anode was proved. Total organic carbon results have shown that almost complete mineralization could be accomplished at higher applied current density with specific electrical charge 22.5 x 10(-2) Ahdm(-3). Mineralization current efficiency was comparatively lower with increasing applied current density. (c) 2006 Elsevier Ltd. All rights reserved.
Keywords:boron-doped diamond;endocrine disrupting chemicals;17 beta-estradiol;peroxodisulfate;hydroxyl radical