title: Biodegradation, ecotoxicity and UV254/H2O2treatment of imidazole, 1-methyl-imidazole and N,N'-alkyl-imidazolium chlorides in water.
abstract: Imidazole-based compounds are used as reagents for the manufacturing of other compounds including imidazolium-based ionic liquids, which have been recently proposed as a green alternative to conventional solvents. Since some imidazole-based compounds have been demonstrated to be harmful to aquatic organisms, the removal of imidazole, 1-methylimidazole, 1-ethyl-3-methyl-imidazolium chloride and 1-butyl-3-methyl-imidazolium chloride from aqueous solutions was attempted by biological oxidation, direct UV254photolysis, and UV254/H2O2process at pH 5.5 and 8.5. Results showed that UV254/H2O2treatment is an effective tool for the removal of the selected compounds at both pHs. In fact, the kinetic constants of the reaction between the photogenerated HO radicals and the four target compounds, estimated by means of both numerical and competition kinetic method, range between 2.32·109M-1s-1and 5.52 ·109M-1s-1. Moreover, an ecotoxicity assessment of the contaminated water before and after initial treatment without further processing was assessed by using two living aquatic organisms: Raphidocelis subcapitata and Daphnia magna. The results of this assessment not only corresponded closely to previous findings (in terms of EC50values) reported in the literature, but also indicated that, in some cases, UV254/H2O2oxidation by-products could be even more toxic than parent compounds.
authors.affiliation: Dipartimento di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica, Politecnico di Bari, Via E. Orabona, 4, 70126, Bari, Italy. Electronic address: danilo.spasiano@poliba.it.
authors.forename: D
authors.initials: D
authors.lastname: Spasiano
authors.affiliation: Dipartimento di Biologia, Università di Napoli Federico II, Via Cinthia, 80126, Napoli, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Siciliano
authors.affiliation: Dipartimento di Ingegneria Civile, Edile ed Ambientale, Università di Napoli Federico II, Via Claudio, 21, 80125, Napoli, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Race
authors.affiliation: Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università di Napoli Federico II, p.le V. Tecchio, 80, 80125, Napoli, Italy. Electronic address: rmarotta@unina.it.
authors.forename: R
authors.initials: R
authors.lastname: Marotta
authors.affiliation: Dipartimento di Biologia, Università di Napoli Federico II, Via Cinthia, 80126, Napoli, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Guida
authors.affiliation: Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università di Napoli Federico II, p.le V. Tecchio, 80, 80125, Napoli, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Andreozzi
authors.affiliation: Dipartimento di Ingegneria Civile, Edile ed Ambientale, Università di Napoli Federico II, Via Claudio, 21, 80125, Napoli, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Pirozzi
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D003621:Daphnia; D006861:Hydrogen Peroxide; D007093:Imidazoles / Q000737:chemistry; D052578:Ionic Liquids / Q000737:chemistry; D014867:Water
chemical_list: D007093:Imidazoles; D052578:Ionic Liquids; D014867:Water; D006861:Hydrogen Peroxide
keywords: Biodegradation; Ecotoxicity; H(2)O(2) photolysis; Imidazole; Ionic liquids; Kinetic modeling