Hypochlorite-mediated degradation and detoxification of sulfathiazole in aqueous solution and soil slurry

Environ Pollut. 2024 Apr 24:124039. doi: 10.1016/j.envpol.2024.124039. Online ahead of print.ABSTRACTAlthough various activated sodium hypochlorite (NaClO) systems were proven to be promising strategies for recalcitrant organics treatment, the direct interaction between NaClO and pollutants without explicit activation is quite limited. In this work, a revolutionary approach to degrade sulfathiazole (STZ) in aqueous and soil slurry by single NaClO without any activator was proposed. The results demonstrated that 100% and 94.11% of STZ could be degraded by 0.025 mM and 5 mM NaClO in water and soil slurry, respectively. The elimination of STZ was shown to involve superoxide anion (O2•-), chlorine oxygen radical (ClO•), and hydroxyl radical (•OH), according to quenching experiments and the analysis of electron paramagnetic resonance. The addition of Cl-, HCO3-, SO42-, and humic acid (HA) marginally impeded the decomposition of STZ, while NO3-, Fe3+, and Mn2+ facilitated the process. The NaClO process exhibited significant removal effectiveness at a neutral initial pH. Moreover, the NaClO facilitated application in various soil samples and water matrices, and the procedure was also successful in effectively eliminating a range of sulfonamides. The suggested NaClO degradation mechanism of STZ was based on the observed intermediates, and the majority of the products exhibited lower ecotoxicity than STZ. Besides, the experiment results by using X-ray diffraction (XRD) and a fou...
Source: Environmental Pollution - Category: Environmental Health Authors: Source Type: research