Efficient carbamazepine removal from wastewater using a continuous three-dimensional electro-Fenton system at natural pH

Abstract

This research presents an innovative approach for removing carbamazepine (CBZ), a persistent pharmaceutical contaminant, using a three-dimensional electro-Fenton (TDEF) system. The preliminary phase involved validating the configuration of the TDEF reactor. First, commercial electrodes, metal-mixed oxide as the anode, and stainless steel as the cathode were selected. After that, a third particulate electrode was introduced, working with two options: vineyard biochar and a lab-made conglomerate of perovskite and carbon black. Additionally, two collector systems were evaluated for easy recovery and reuse of this three-dimensional particulate electrode: a thermoplastic tube and a silicone bag. Among the tested configurations, the perovskite conglomerate retained within a silicone bag proved the most effective, achieving a 91 % CBZ removal efficiency at a natural pH (6.5) during a 5-hour batch operation. Considering excellent results, the system's efficacy was confirmed working on fortified tertiary wastewater (FTW) in continuous mode, emphasizing the adaptability to real-world conditions. Moreover, the reusability of microparticles was confirmed for three consecutive cycles, as well as through the characterization study using FTIR, without important modifications in the material after use. Results confirmed the technology's potential for removing CBZ operating with real conditions. Thus, the proposed process represents an alternative treatment to remove CBZ efficiently in a wide range of concentrations from real wastewater in a continuous treatment with a reasonable energy cost (ca. 27 kW/h·gCZP). This novel system represents a cost-effective, straightforward experimental setup suitable for future scaling and industrial applications.