Photodegradation of clopyralid in TiO2 suspensions: Identification of intermediates and reaction pathways

Impact of natural organic matter on the degradation of 2,4-dichlorophenoxy acetic acid in a fluidized bed photocatalytic reactor

“…To better assess the effect of NOM on different mechanisms, methanol of 0.1 M was used in this experiment as Å OH scavenger. Methanol is UV transparent and does not compete with 2,4-D for adsorption sites, but it strongly scavenges Å OH [11,13,35]. Fig.…”

“…According to the literature, the pH value of the medium plays a major role in influencing the efficiency of photocatalytic processes by affecting oxidation mechanisms [9][10][11][12]. Indeed, the pH of the medium is the key factor in adsorption and consequent oxidation pathways [11,13,14]. Tunesi et al [11] showed that the electrostatic repulsion between the micropollutant anion and the oxide surface caused reducing the adsorption at high pH.…”

Comparative Assessment of the Photocatalytic Efficiency of TiO2 Wackherr in the Removal of Clopyralid from Various Types of Water

“…Moreover, the pH influences the sizes of TiO 2 aggregates, interaction of the solvent molecules with the catalyst and the type of radicals or intermediates formed during the photocatalytic reaction (Muneer & Bahnemann, 2002;Šojić at al., 2009;Tizaoui et al, 2011). All of these factors have a significant effect on the adsorption of solutes on TiO 2 surfaces and, as a result, on the observed photodegradation rates.…”

“…Because of their frequent use, chemical stability and resistance to biodegradation, they are encountered in waste waters, and, due to their hazardous effects on ecosystems and human health, their removal is imperative (Stapleton et al, 2006). With this in mind, we have recently paid significant attention to the study of the model compounds (Abramović et al, 2003;Abramović et al, 2004aAbramović et al, , 2004b and pyridine containing pesticides (Abramović et al, 2007;Šojić et al, 2009;Guzsvány et al, 2010;Šojić et al, 2010a, 2010bBanić et al, 2011).…”

“…Due to these properties, CLP has recently been reported to occur in drinking water at concentrations above the Permitted Concentration Value of 0.1 μg L -1 for an individual pesticide (EU directive 98/83/EC). Although the occurrence of CLP in surface, ground and drinking waters has been widely reported, there are only a few studies concerning with its photocatalytic removal from water (Šojić et al, 2009;Šojić et al, 2010a, 2010bTizaoui et al, 2011). These studies showed that the degradation of this herbicide takes place most effectively in the presence of Degussa P25 as photocatalyst.…”