Electrochemical oxidation of ethylenediaminetetraacetic acid (EDTA) on BDD electrodes: Application to wastewater treatment

The electrochem. oxidn. of EDTA was studied at boron-doped diamond (BDD) electrodes. Cyclic voltammetry in the potential region of water stability showed that EDTA is oxidized in an irreversible 2-electron-transfer mechanism. No fouling phenomena were noticed on the electrode surface. At high anode potential, an oxidn. mechanism of EDTA involving hydroxyl radicals, formed during water discharge, was proposed. The model previously developed for org. oxidn. at nonactive anodes was successfully used in order to predict the trends of COD and instantaneous current efficiency (ICE) during EDTA oxidn. on BDD electrodes. Bulk electrolyzes were performed under different regimes. The very good fit between the exptl. results and theor. values confirmed that EDTA oxidn. at the BDD electrode in the potential region of electrolyte decompn. was a fast reaction. [on SciFinder (R)]