Photocatalytic ozonation using doped TiO2 catalysts for the removal of parabens in water
João F. Gomes , Inês Leal , Katarzyna Bednarczyk , Marta Gmurek , Marek Stelmachowski , Magdalena Diak , M. Emília Quinta-Ferreira , Raquel Costa , Rosa M. Quinta-Ferreira , Rui C. Martins
AbstractConventional wastewater treatments are inefficient for the removal of parabens. The aim of this study was finding a suitable solution using ozone and UVA irradiation combined with TiO2 catalysts doped with different noble metals (Ag, Pt, Pd, Au). Photocatalytic ozonation required lower amounts of ozone for higher efficiency on the removal of parabens, chemical oxygen demand (COD) and total organic carbon (TOC). The best catalyst for the initial contaminants degradation was 0.5% Ag-TiO2 leading to total parabens removal using 46 mgO3/L. Due to the relative low mineralization achieved, the toxicity of the treated solutions was still compared with the initial one over several species (Vibrio fischeri, Lepidium sativum and Corbicula fluminea). All the treatments applied led to a clear decrease on the toxicity compared with initial mixture of parabens. From an economical point of view, it was concluded that the presence of UVA irradiation increased the energy consumption compared with catalytic ozonation with these catalysts but it can decrease the time of reaction. From the by-products analysis, it was concluded that hydroxylation appears to be the most significant reaction pathway and the main responsible for parabens degradation.
|Other language title versions|
|Journal series||Science of the Total Environment, ISSN 0048-9697, (A 40 pkt)|
|Publication size in sheets||0.55|
|Keywords in English||photocatalytic ozonation, parabens degradation, doped TiO2, toxicity, cost evaluation, by-products analysis|
|License||Journal (articles only); published final; ; after publication|
|Score|| = 40.0, 20-12-2017, ArticleFromJournal|
= 40.0, 20-12-2017, ArticleFromJournal
|Publication indicators||: 2016 = 4.9 (2) - 2016=5.102 (5)|
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