Sequential high-recovery nanofiltration and electrochemical degradation for the treatment of pharmaceutical wastewater

• Published in: Water research (Oxford) 2024-08, Vol.259, p.121832, Article 121832
• Main Authors: Fang, Chenyi, Garcia-Rodriguez, Orlando, Yang, Liming, Zhou, Yaochang, Imbrogno, Joseph, Swenson, Tim M., Lefebvre, Olivier, Zhang, Sui
• Format: Article
• Language: English
• Subjects: Azithromycin; Drug Industry; Electrochemical oxidation; Electrochemical Techniques; Energy efficiency; Filtration; Long-term stability; Nanofiltration; Nanotechnology; Oxidation-Reduction; Pharmaceutical Preparations; Real pharmaceutical wastewater treatment; Waste Disposal, Fluid - methods; Wastewater - chemistry; Water Pollutants, Chemical - chemistry; Water Purification - methods
• ISSN: 0043-1354; 1879-2448; 1879-2448
• DOI: 10.1016/j.watres.2024.121832

•Combining nanofiltration and electrochemical oxidation for antibiotic removal.•Concentration of wastewater at 95 % recovery with long-term stability.•Significant enhancement in mass transfer rates of organics to electrodes.•Complete degradation of antibiotics by electrochemical process.•Low overall energy consumption for treating pharmaceutical wastewater. The presence of antibiotics in aquatic ecosystems poses a significant concern for public health and aquatic life, owing to their contribution to the proliferation of antibiotic-resistant bacteria. Effective wastewater treatment strategies are needed to ensure that discharges from pharmaceutical manufacturing facilities are adequately controlled. Here we propose the sequential use of nanofiltration (NF) for concentrating a real pharmaceutical effluent derived from azithromycin production, followed by electrochemical oxidation for thorough removal of pharmaceutical compounds. The NF membrane demonstrated its capability to concentrate wastewater at a high recovery value of 95 % and 99.7 ± 0.2 % rejection to azithromycin. The subsequent electrochemical oxidation process completely degraded azithromycin in the concentrate within 30 min and reduced total organic carbon by 95 % in 180 min. Such integrated treatment approach minimized the electrochemically-treated volume through a low-energy membrane approach and enhanced mass transfer towards the electrodes, therefore driving the process toward zero-liquid-discharge objectives. Overall, our integrated approach holds promises for cost-effective and sustainable removal of trace pharmaceutical compounds and other organics in pharmaceutical wastewater. [Display omitted]