Photodegradation of imipramine (IMI), a widely used tricyclic antidepressant, in the presence of Fe(III) oxalate and potassium persulfate (PS) was studied for the first time by combination of steady state and laser flash photolysis. It was demonstrated that Fe(III) oxalate system exhibits an effective photooxidation of IMI due to the formation of reactive oxygen species (ROS) with a very high quantum yield, φROS(308 nm) ∼0.3. The quantum yield of the most important ROS, hydroxyl radical, was also measured for the first time (φOH(308 nm) = 0.25 ± 0.02) as well as the rate constant of the reaction between •OH radical and IMI (kOH = (1.5 ± 0.1) ×1010 M−1s−1). Nature and spectral properties of short lived organic radicals formed in this reaction were also determined experimentally and proved by quantum-chemical calculations. At a IMI concentration of less than 10 µM it is possible to achieve full disappearance of the initial compound in Fe(III)-oxalate system. Main aromatic by-products of the IMI oxidation are connected with its consequent hydroxylation and elimination of aliphatic substituent. Complete degradation of both IMI and all aromatic byproducts needs joint application of Fe(III) oxalate and PS, as additional oxidizing agent. Combined Fe(III) oxalate – PS system demonstrates high photoactivity under UV irradiation and could be used for the effective degradation of IMI and its close analogues in aqueous media.
|Журнал||Journal of Photochemistry and Photobiology A: Chemistry|
|Состояние||Опубликовано - 1 янв. 2022|
Предметные области OECD FOS+WOS
- 2.04 ХИМИЧЕСКИЕ ТЕХНОЛОГИИ
- 1.04 ХИМИЧЕСКИЕ НАУКИ