Decomposition byproducts induced by gamma radiation and their toxicity: the case of 2-nitrophenol. Issue 8 (18th April 2018)

• Record Type: Journal Article
• Authors: Alsager, Omar A.; Basfar, Ahmed A.; Muneer, Majid
• Is Part Of: Environmental technology. Volume 39:Issue 8(2018)
• Page Start: 967
• Page End: 976
• Publication Date: 2018-04-18
• Subjects: Gamma radiation -- 2-nitrophenol -- byproducts and toxicity -- in-solution degradation -- detoxification; Environmental engineering -- Periodicals; Environmental protection -- Periodicals; 628.05
• DOI: 10.1080/09593330.2017.1317840
• Languages: English
• ISSNs: 0959-3330

Abstract

ABSTRACT: The induced degradation and detoxification of 2-nitrophenol (2-NP) in aqueous media by gamma irradiation were carefully evaluated in this study. Gamma radiation at absorbed doses as low as 20 kGy was able to degrade 2-NP to reach a removal of at least 85% across the investigated range of concentration (50–150 ppm). 2-NP breaks down to aromatic-based compounds with increasing number of byproducts upon increasing the radiation treatment from the absorbed dose of 50% decomposition (D50 ) to the absorbed dose of 90% decomposition (D90 ), after which no byproducts could be detected, indicating the formation of undetectable aliphatic hydrocarbons, insoluble, or volatile byproducts. Toxicology studies showed that the degradation of 2-NP under absorbed doses up to D90 resulted in a more toxic byproduct than the parent compound, and a remarkable reduction in the toxicity was observed with the irradiated samples with absorbed doses above D90 . Varying the pH of the media to acidic or basic conditions did not significantly alter the degradation behavior of 2-NP. However, a notable improvement of the detoxification was associated with the samples of acidic pH. Adding 0.5% of H2 O2 to 2-NP solutions had a positive effect by reducing D90 by a factor of nine and diminishing the toxicity by twofolds. GRAPHICAL ABSTRACT: