Simulated solar photo-assisted decomposition of peroxymonosulfate. Radiation filtering and operational variables influence on the oxidation of aqueous bezafibrate

• Published in: Water research (Oxford) 2019-10, Vol.162, p.383-393
• Main Authors: Solís, Rafael R., Rivas, F. Javier, Chávez, Ana M., Dionysiou, Dionysios D.
• Format: Article
• Language: English
• Subjects: Bezafibrate; Intermediates; Peroxymonosulfate; Simulated solar radiation
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2019.06.063

This work investigates the potential of the combination of peroxymonosulfate (PMS) and simulated solar radiation (λ > 300 nm) to remove bezafibrate from aqueous solution. Different solar light filters indicate a higher removal efficiency as the wavelength range used moves to the more energetic region of the solar spectrum. The system PMS/Daylight (300–800 nm) eliminates bezafibrate (1 mg L−1) in less than 30 min under the best conditions used in this study (CPMS = 4·10−4 M) with no pH control (acidic pH). The efficiency of the process significantly improves under alkaline conditions (pH = 10), likely due to a higher PMS photolysis rate. Experiments conducted at different initial concentration of PMS and bezafibrate suggest first order regarding PMS and different from 1 in the case of bezafibrate. Intermediates generated at the beginning of the process have been tentatively identified to propose a hypothetical reaction pathway and to estimate their toxicity. [Display omitted] •Solar light activates PMS for the oxidation of bezafibrate.•Radiation effectiveness UVC > UVB > UVA components of the solar spectrum.•First order kinetics regarding PMS and different from 1 for bezafibrate.•11 intermediates detected in the bezafibrate oxidation by PMS and solar light.