- Ionic liquids (ILs) are considered as an alternative to traditional
industrial organic solvents. To date, there are no papers about their
detenction in effluents and in surface water, and they have emerged as
contaminants within the frame of the Horizon Program due to their high
solubility in water and poor biodegrability. The present work investigated
the photocatalytic degradation of four imidazole-based compounds
(imidazole, 1-methylimidazole, 1-ethyl-3-methyl-imidazolium chloride and 1-
butyl-3-methyl-imidazolium chloride) by means of UV254/H2O2 ad
advanced oxidation process in a complex aqueous matrix from the outlet
of a wastewater treatment plant. The degradation was compared to the
previous investigated photodegradation in bidistilled water and a
mathematical model was proposed considering the overall role of the
different scavengers in the competition reactions with photogenerated
•OH radicals. In addition, a chronic toxicity assay using the freshwater
crustacean Daphnia magna was employed for evaluating the ecotoxicity of
photocatalytically treated solutions. The results highlighted that the effects
of untreated and treated solutions on D. magna survival decreased with
increasing lipophilicity and that it was necessary a fourth generation of ILs
by-products to reduce the long-term effects of treated solutions. Delayed
reproductive maturity and reduced fecundity were found regardless of
treatment
