Mineralization of cefoperazone in acid medium by the microwave discharge electrodeless lamp irradiated photoelectro-Fenton using a RuO2/Ti or boron-doped diamond anode

Abstract The mineralization of 125 mL of 50–300 mg L −1 cefoperazone (CFPZ) has been comparatively studied by electrochemical advanced oxidation processes (EAOPs) like anodic oxidation (AO), electro-Fenton (EF) and photoelectro-Fenton (PEF) with a RuO 2 /Ti or boron-doped diamond (BDD) anode and an activated carbon fiber (ACF) cathode. A microwave discharge electrodeless lamp (MDEL) was used as the UV source in PEF process. CFPZ decays always followed pseudo-first-order kinetics and their constant rates increased in the order: AO  2 /Ti, while the most potent BDD-MDEL-PEF gave 88% mineralization under its optimum conditions of 0.36 A, pH 3.0 and 1.0 mmol L −1 Fe 2+ . The synergistic mechanisms were explored by quantifying the electrogenerated H 2 O 2 and formed • OH, in which 2.27 and 2.58 mmol L -1 H 2 O 2 were accumulated in AO-H 2 O 2 with RuO 2 /Ti or BDD anode, respectively, while 92.0 and 263.5 μmol L -1 • OH were generated in EF with RuO 2 /Ti or BDD anode, respectively. The oxidation power of EAOPs with different anodes was also compared by measuring the evolutions of NO 3 − and NH 4 + as well as four generated carboxylic acids including oxalic, oxamic, formic and fumaric acids.