Catalytic ozonation using spent battery-based (SB) catalysts for dyes, micropollutant removal and disinfection

This study aimed to explore the use of three different Spent battery-based (SB) catalysts of ozonation to remove organic contaminants and disinfection. The SB catalysts studied were prepared from three types of spent batteries' electrolytic pastes: Panasonic Super Hyper (SH), Panasonic Alkaline (AK) and yellow Rayovac (RV). Its characterization was made through FTIR, SEM, XRD, XRS and BET. The catalytic ozonation system was optimized through Central Composite Design (CCD) 22 with three replications at the central point, to determine the best catalyst dose and ozone dose (O3) to be applied. The degradation of 5 dyes and atrazine (ATZ) in ultrapure water (UW) and ATZ in secondary effluent (SE) and the disinfection was performed. The SB catalysts resulted in enhanced efficacy compared to ozonation alone. However, the AK showed better efficiency compared to the other catalysts in cleaner water matrices. When applied in SE the results showed equivalent efficiencies in comparison with single O3. The germination and elongation of Eruca sativa were not affected by the SB catalysts applied to O3, demonstrating that the effluent did not present toxicity either before or after the treatments. It highlights that the SB catalysts are capable of improving the organic pollutants removal.