Improvement of carbamazepine removal through biodegradation coupled with peroxymonosulfate-based Fenton oxidation

Abstract

This study addresses carbamazepine (CBZ) removal from water using a metal ions/peroxymonosulfate (PMS) system and biological treatment by single soil bacteria strain in groundwater conditions (i.e., aerobic/anoxic and 15 oC). Although the PMS activation capacity of metal ions for the degradation of CBZ follows the order Mn (II) < Cu (II) < Fe (II) < Co (II), Fe (II) was chosen in this study because of its non-toxicity relative to Co (II). The biological process involving Pseudomonas jinjuensis decreased the residual CBZ in pre-treated water by 56.7-68.0% at low pH. The CBZ removal was largely mediated by the laccase activity and cell adsorption. Despite the decreasing viability with time, P. jinjuensis still acted as a biodegrader for residual CBZ, with the dual process removing approximately 83.6% of the CBZ; from initial 10 μM to 1.3 μM under aerobic and 1.7 μM under anoxic condition. This study findings highlight a potential of the dual ferrous iron-activated PMS pretreatment and biological process for removing CBZ in groundwater.