Electrooxidation of glyphosate herbicide at different DSA compositions: pH, concentration and supporting electrolyte effect

This paper has investigated the electrochemical oxidation of glyphosate herbicide (GH) on RuO₂ and IrO₂ dimensionally stable anode (DSA^®) electrodes. Electrolysis was achieved under galvanostatic control as a function of pH, GH concentration, supporting electrolyte, and current density. The influence of the oxide composition on GH degradation seems to be significant in the absence of chloride; Ti/Ir_0.30Sn_0.70O₂ is the best electrode material to oxidize GH. GH oxidation is favored at low pH values. The use of chloride medium increases the oxidizing power and the influence of the oxide composition is meaningless. At 30 mA cm⁻² and 4 h of electrolysis, complete GH removal from the electrolyzed solution has been obtained. In chloride medium, application of 50 mA cm⁻² leads to virtually total mineralization (release of phosphate ions = 91%) for all the evaluated oxide materials.