(527g) Sustainable Degradation of Ciprofloxacin in Water By the Electro?Peroxone Process Via a Graphite Felt Electrode System

Over the last few decades, excessive, unregulated usage and reckless disposal of antibiotics have led to the development of antibiotic resistance in bacteria. Additionally, untreated or partially treated pharmaceutical effluents are often discharged into water bodies in an unregulated manner, especially in developing countries. With the increasing prevalence of antibiotic resistance across the globe, previously curable diseases are becoming challenging to handle due to the advent of superbugs. It is imperative to ensure a complete treatment and removal of antibiotics and pharmaceuticals before discharging them into water bodies. Unfortunately, conventional treatment plants are not adept in removing such complex, emerging contaminants. The field of advanced oxidation processes is a rapidly evolving and promising treatment strategy for the abatement of emerging contaminants such as pharmaceutical compounds. Electro-peroxone, a propitious advanced oxidation process, is investigated in this work for the treatment of pharmaceuticals, by considering ciprofloxacin, a model antibiotic drug as the target contaminant. The electro-peroxone system houses electrodes of graphite felt that help form hydrogen peroxide, an oxidant, in situ (see schematic). The viability of the carbon-based graphite felt system in the generation of reactive oxygen species and in ciprofloxacin degradation is investigated in detail. A comparison of the electro-peroxone with two benchmark processes, namely, electrolysis and ozonation, is also carried out. Both electro-peroxone and ozonation are show promise in the removal of the model contaminant and the in situ generation of H2O2 and •OH is estimated. This is a one-of-a-kind study involving graphite felt as both anode and cathode and achieves an in situ generation of H2O2 of 47 mg/L in 120 min and •OH of 140 μM within 60 min of electroperoxone. Besides, the efficacy of the system in contaminant degradation is examined at voltammetric and galvanostatic modes of operation. Ozonation and electro-peroxone processes achieved an efficiency between 97% and complete removal of ciprofloxacin in less than 1 hour. This novel system generates several times higher hydrogen peroxide than the existing graphite electrode system, making it more efficient in radical generation and pollutant abatement (see illustration). This graphite felt-based electro-peroxone system, on further optimization and up-scaling, can be a promising strategy for abating pharmaceutical compounds and effluents.

Reference:

Srinivasan, Ramya. "Sustainable degradation of ciprofloxacin in water by the electro-peroxone process via a graphite felt electrode system." Discover Water 4.1 (2024): 1-8.