title: Mineralization of paracetamol in aqueous solution with advanced oxidation processes.
abstract: Paracetamol is a common analgesic drug widely used in all regions of the world more than hundred tonnes per year and it poses a great problem for the aquatic environment. Its phenolic intermediates are classified as persistent organic pollutants and toxic for the environment as well as human beings. In the present study, the irradiation of aqueous solutions of paracetamol with 60Co gamma-rays was examined on a laboratory scale and its degradation path was suggested with detected radiolysis products. The synergic effect of ozone on gamma-irradiation was investigated by preliminary ozonation before irradiation which reduced the irradiation dose from 5 to 3 kGy to completely remove paracetamol and its toxic intermediate hydroquinone from 6 to 4 kGy as well as increasing the radiation chemical yield (Gi values 1.36 and 1.66 in the absence and presence of ozone, respectively). The observed amount of formed hydroquinone was also decreased in the presence of ozone. There is a decrease in pH from 6.4 to 5.2 and dissolved oxygen consumed, which is up to 0.8 mg l(-1), to form some peroxyl radicals used for oxidation. Analytical measurements were carried out with gas chromatography/mass spectrometry and ion chromatography (IC) both qualitatively and quantitatively. Amounts of paracetamol and hydroquinone were measured with gas chromatography after trimethylsilane derivatization. Small aliphatic acids, such as acetic acid, formic acid and oxalic acid, were measured quantitatively with IC as well as inorganic ions (nitrite and nitrate) in which their yields increase with irradiation.
authors.affiliation: a Department of Chemistry , Hacettepe University , Beytepe , 06800 Ankara , Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Torun
authors.forename: Özge
authors.initials: Ö
authors.lastname: Gültekin
authors.forename: Dilek
authors.initials: D
authors.lastname: Şolpan
authors.forename: Olgun
authors.initials: O
authors.lastname: Güven
mesh_terms: D000082:Acetaminophen / Q000737:chemistry* / Q000528:radiation effects; D005720:Gamma Rays; D008401:Gas Chromatography-Mass Spectrometry; D010084:Oxidation-Reduction; D010126:Ozone; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D014874:Water Pollutants, Chemical; D000082:Acetaminophen; D010126:Ozone
keywords: advanced oxidation processes; gamma-irradiation; mineralization; paracetamol; pharmaceutical wastes