Diclofenac removal from water by ozone and photolytic TiO₂ catalysed processes

Abstract

BACKGROUND: The aim of this work was to establish the efficiency of single ozonation at different pH levels (5, 7 and 9) and with different TiO 2 photolytic oxidizing systems (O 2 /UV-A/TiO 2 , O 3 /UV-A/TiO 2 or UV-A/TiO 2 ) for diclofenac removal from water, with especial emphasis on mineralization of the organic matter.

Some ozone advanced oxidation processes to improve the biological removal of selected pharmaceutical contaminants from urban wastewater

“…Also, photocatalytic oxidation with the iron catalysts used did not either lead to any pharmaceutical degradation As shown in Figure 6, as example, ozone processes were the only ones among those studied here that effectively allowed significant or even total elimination of the pharmaceuticals studied. This, on the other hand, confirmed previous results of the ozonation of some of these compounds in ultrapure water at a much higher concentration [33][34][35]. It should be highlighted; however, that total removal means that pharmaceuticals were in water at concentrations below their detection limit of the HPLC method applied In Figure 8, on the other hand, the time changes observed in the 254 nm absorption of treated samples is presented.…”

Removal and reduction of selected organic micro-pollutants in effluent sewage by the ozone-based oxidation processes

“…One was that ozone acted as an electron acceptor, and the other was that hydrogen peroxide usually formed during direct ozonation reactions also acted as an electron acceptor, both leading to higher amount of hydroxyl radicals per photon absorbed and also reducing the photohole-electron recombination process to some extent [38]. The enhancement was also observed for the PC/O 3 combined oxidation of several organic compounds in water solution [38,39].…”

Oxidation of non-steroidal anti-inflammatory drugs with aqueous permanganate

“…4, were the reaction begins by permanganate attack to the electron richest ring, i.e. the non-chlorinated one, as it happens with other electrophilic disinfectants, such as free chlorine Soufan et al, 2012) or stronger (radicallary) oxidants (García-Araya et al, 2010).…”