Ciprofloxacin removal catalysed by conductive carbon materials

Abstract

Current wastewater treatment technologies are not effective in the removal of pharmaceuticals. In anaerobic bioreactors, the electrons produced during the oxidation of organic matter can potentially be used for the biological reduction of pharmaceuticals. However, these reactions occur generally at a slow rate, due to electron transfer limitations, and might be accelerated through redox mediators (RM). Carbon nanomaterials (CM) have been effective RM in the biological reduction of other pollutants. For instance, CNT@2%Fe were found to increase 76-fold the biological reduction of Acid Orange 10. The magnetic properties of those composites allow their easier recover after the process by using a magnetic field. In this study, CNT and CNT@2%Fe were studied in the anaerobic removal of Ciprofloxacin (CIP). Furthermore, the potential contribution of adsorption and biodegradation processes for CIP removal was assessed. Toxicity assessment is highly important as it is desired that the products formed after the process are not more toxic than the initial compound. Moreover, the evaluation of the possible contribution of nanomaterials used in the process for the final toxic effect of threated solution, is crucial. In this sense, the detoxification of the treated solutions was evaluated towards Vibrio fischeri.