Experimental and modeling evidence of hydroxyl radical production in iron electrocoagulation as a new mechanism for contaminant transformation in bicarbonate electrolyte

••OH induced contaminant oxidation by iron EC in bicarbonate electrolyte.•High yield of •OH occurred at pH 8.5 in bicarbonate electrolyte.•Formation of adsorbed Fe(II)-carbonate complexes favored high •OH yields.•A new kinetic model can describe •OH production and contaminant oxidation.•Results highlighted the •OH-based advanced oxidation process in iron EC.