![Sample our Environment & Sustainability journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5935/TOC-Subject-Sample-2021-Environment-Sustainability.jpg"})
Abstract
A kinetic study of the RB‐sensitized photooxygenation of a series of chlorohydroxyaromatic (ClArOH) water contaminants (phenolic and dihydroxybenzene derivatives) has been carried out. In addition, an exhaustive study on the possible interactions of RB electronically excited triplet and singlet states with ClArOH was also developed. The determination of relative rates of oxygen uptake upon sensitized irradiation, employing auxiliar selective quenchers of oxygen active species, indicate the contribution of both singlet molecular oxygen (ca. 71%) and Superoxide ion (ca. 26%) as the reactive pathways for ClArOH degradation. The substitution by chlorine atoms in position meta greatly decrease the photooxygenation rate of the phenolic derivatives. For the dihydroxybenzene series, increase in nuclear chlorination parallels a decrease in the photodegradation rate.
Outdoors sensitized solar irradiation experiments on different ClArOH mixtures leads to measurable levels of oxygen after a few minutes exposure. From the environmental point of view, and ruling out the possibility of direct‐irradiation photoreactions, sensitized photooxygenation appears as an alternative pathway for ClArOH degradation, in competence with other naturally‐occurring photoprocesses involving reactive transient species.
Notes
Author to whom correspondence should be addressed.