ABSTRACT
The photolysis of aqueous ozone has been the subject of many works aimed at establishing the mechanism of reactions and the kinetics of the photolytic process. Peyton and Glaze1 reported that the photolysis of dissolved ozone directly yields hydrogen peroxide, then the photolysis of the hydrogen peroxide formed and/or its reaction with ozone initiates the mechanism of free radical reactions leading to the hydroxyl radical:
(9.1)
(9.2)
and Reaction (8.1), etc. (see Table 2.3 or Table 2.4). According to these observations, the O3/UV system is the most complete ozone
system involving an advanced oxidation process since there could be up to three possible initiation reactions for the generation of hydroxyl radicals. These reactions are possibly due to the initiating species present in the water [see Reaction (7.4) and Reaction (7.10)], the free radicals formed from the photolysis of hydrogen peroxide, Reaction (9.2), and the free radicals formed from the ozone-hydrogen peroxide Reaction (8.1).
