Combined electrochemical treatment/biological process for the removal of a commercial herbicide solution, U46D®

The electrochemical pretreatment shortened the duration of the biodegradation. For non-pretreated U46D® (100 mg L−1 2,4-D), mineralization remained limited until 6 days of culture (33.7% DOC removal), and total removal of the DOC was observed after 8 days. For pretreated U46D®, 63.7% decrease until the fifth day of culture was observed but total mineralization was not reached at the end of culture (72.1%). An overall mineralization yield during the coupled process of 82.1% was therefore reached. The presence of refractory compounds generated during the electrochemical pretreatment in small concentration was therefore shown.