10.6084/m9.figshare.11555484.v1 Landry Biyoghe Bi Ndong Landry Biyoghe Bi Ndong Frank Herve Yeo Kanfolo Frank Herve Yeo Kanfolo Predominance role of the superoxide radical over the hydroxyl radical in the dechlorination of trichloroethene in aqueous phase using Cu doped TiO<sub>2</sub> Taylor & Francis Group 2020 Cu-TiO2 UV light superoxide radical hydroxyl radical trichloroethene polluted water remediation 2020-01-08 21:20:16 Journal contribution https://tandf.figshare.com/articles/journal_contribution/Predominance_role_of_the_superoxide_radical_over_the_hydroxyl_radical_in_the_dechlorination_of_trichloroethene_in_aqueous_phase_using_Cu_doped_TiO_sub_2_sub_/11555484 <p>Trichloroethylene (TCE), a frequently used chlorinated solvent has been completely degraded in aqueous solution over the as-synthesised Cu-TiO<sub>2</sub> irradiated with UV light. The effect of pH and the role played by specific generated reactive oxygen species in the mineralisation process were evaluated. Cu-TiO<sub>2</sub> was synthesised and characterised according to our previous study. The photodegradation results, which followed the pseudo-first-order kinetic model, revealed that pH had a negligible effect on the degradation as the complete dechlorination occurred in all adjusted pH solutions. In addition, probe compound tests using nitrobenzene and tetrachloromethane suggested that the hydroxyl radical (<sup>•</sup>OH) is mainly generated when coupling UV with Cu-TiO<sub>2</sub>, and the superoxide radical anion (O<sub>2</sub><sup>•−</sup>) is highly generated when UV is applied alone. Free radical quenching studies demonstrated that O<sub>2</sub><sup>•−</sup> is the major radical responsible for the degradation of TCE compared to <sup>•</sup>OH. The results obtained in the present study can serve as a support for further studies on the removal of TCE using UV coupling catalyst.</p>