• An Activated Carbon (AC) bed simultaneously works as adsorbent and electrode. • A DOE was used to study the effect of AC on the performance of an EF reactor. • The effect of AC source was found to be the dominant factor on EF performance. • AC mesh separation and acid pre-treatment have modest effects. • Excessive amounts of the Fe results in limited performance of the EF reactor.

Carbamazepine (CBZ) is one of the most frequently detected organic compounds in the aquatic environment. Due to its bio-persistence and toxicity for human and environment its removal has become an important issue. The performance of electrochemical oxidation process and in situ reactive oxygen species (ROS) such as O₃, H₂O₂, etc. production for CBZ removal have been studied using Ti/PbO₂ cylindrical mesh anode in presence of Na₂SO₄ as supporting electrolyte in a batch electrochemical reactor. In this integrated process, direct oxidation at anode and indirect oxidation by in situ electrogenerated ROS can occur simultaneously. The effect of several factors such electrolysis time, current intensity, initial pH and oxygen flux were investigated by means of an experimental design methodology, using a 2⁴ factorial matrix. CBZ removal of 83.93% was obtained and the most influential parameters turned out to be electrolysis time, current intensity and oxygen flux. Later, the optimal experimental values for CBZ degradation were obtained by means of a central composite design. The best operating conditions accomplished by Design Expert^® software are the following: 110 min of electrolysis at 3.0 A, pH = 7.05 and 2.8 L O₂/min. Under these optimal conditions, the model prediction (82.44%) fits very well with the experimental response (83.90 ± 0.8%). Furthermore, chemical oxygen demand decrease was quantified. Our results illustrated significant removal efficiency for the CBZ in optimized condition with second order kinetic reaction.