Bisphenol S degradation using Fe-SBA-15/UV/US/peroxymonosulfate: performance optimization, biodegradability, mineralization and toxicity studies

The presented research was to prepare the iron-doped SBA-15 catalyst (Fe-SBA-15) and to apply it as a heterogeneous catalyst in the ultrasound (US) and ultraviolet (UV) processes for developing the heterogeneous activation of peroxymonosulfate and degrading the bisphenol S (BPS). The effect of important reaction parameters on the removal of BPS by the Fe-SBA-15/UV/US/PMS process was investigated. Simultaneous use of US and UV irradiations with Fe-SBA-15 for activation of PMS led to significant degradation of BPS. The BPS degradation rate was developed at the presence of higher PMS and Fe-SBA-15 dosages at pH = 7. It was also found, based on the quenching tests, that both OH• and SO4 •- radicals have a superior role in the degradation of BPS and dominant species are the sulfate radicals. Complete removal of BPS and 67 mineralization degree was obtained at the optimum conditions after 60 min reaction. Based on the activated sludge inhibition assessment, it was detected that the toxicity of the solution significantly decreased in this system. Moreover, according to the BOD5/COD ratio of samples, it was found that the biodegradability of treated samples is improved. Furthermore, it was confirmed that Fe-SBA-15 can be reused in five consecutive cycles and the removal efficiency was acceptable at 94.2. © 2019 Desalination Publications. All rights reserved.