Electrochemical advanced oxidation process using DiaChem (r) electrodes

The Electrochemical Advanced Oxidation Process (EAOP) using boron doped diamond (Dia Chem®, registered trademark of CONDIAS GmbH) has been studied for wastewater treatment and freshwater disinfection. DiaChem® electrodes consist of preferentially metallic base materials coated with a conductive polycrystalline diamond film by hot-filament chemical vapour deposition. They exhibit high overpotential for water electrolysis as well as high chemical inertness and extended lifetime. In particular the high overpotential for water decomposition opens the widest known electrochemical window, allowing the energy efficient production of hydroxyl radicals directly from aqueous solutions. The hydroxyl radicals on the other hand are effectively used for the oxidation of pollutants. The EAOP using DiaChem® electrodes thus achieves the direct and, if necessary, complete decomposition of even hazardous or persistent pollutants in different wastewaters. Current efficiencies of more than 90 %, also without the use of additives for hydroxyl radical generation have been demonstrated. Additionally, for freshwater preparation diamond electrodes obtained disinfection with and without the support of chlorine.