Performance improvement of the photocatalytic process for the degradation of pharmaceutical compounds using new POM/polymer photocatalysts

International audienceIn the last few years, pharmaceutical compounds classified as emerging pollutants have attracted the attention of many researchers, due to their massive presence in soil, surface, sewage, groundwater and drinking water, as well as to their harmful effects on human health and the environment. In this context, the degradation of four drugs with different chemical structures, Ciprofloxacin, Oxytetracycline, Ibuprofen and Erythromycin was investigated. Indeed, in this paper, we studied the impact of the presence in the aqueous solution of a newly developed POM/polymer composite on the removal of these different drugs from water. Synthesis details and characterizations of these materials have already been reported within our group. The various experiments carried out during this study revealed that the presence of the phosphomolybdic acid-based composite was not essential for the total degradation of Ciprofloxacin and Oxytetracycline which could be totally removed from water by simple photolysis under UV-Visible lamp irradiation. However, under the same experimental conditions, the use of this photocatalyst was indispensable for the total mineralization of Ibuprofen, more recalcitrant than the other selected drugs. In fact, only 20% of this pharmaceutical was degraded by simple photolysis vs. 100% and 94% upon respectively, 90 min of UV-Visible lamp and solar irradiation, in the presence of the phosphomolybdic acid-based composite which was more pertinent than the usually used photocatalyst, namely titanium dioxide. The Ibuprofen degradation pathway was identified thanks to mass spectrometry analysis, conducted at different time intervals. The obtained results demonstrated also that POM/polymer composite inhibits the degradation of Erythromycin through the formation of more toxic intermediates than the original dru