Radiolytic degradation of carbaryl in aqueous solution by gamma-irradiation/H2O2 process
Dilek Şolpan1, Khalid Elmamoun Ahmed Ibrahim2, Abdalla Ahmed Elbashir3
1Hacettepe University, Department of Chemistry, 06800, Beytepe, Ankara, Turkey.
Abstract:
In this study the synergetic effect of gamma-ray and hydrogen peroxide on the degradation of carbaryl in aqueous solution were investigated. Aqueous solution of carbaryl was exposed to five different irradiation doses in the presence and absence of hydrogen peroxide. The intermediate species and aliphatic acids formed during irradiation were determined by Gas chromatography-Mass spectrometer and Ion Chromatography, respectively. It was found that the gamma-irradiation accelerate the degradation process of carbaryl with and without hydrogen peroxide. The inconstancy in pH, dissolved oxygen and total acidity was evaluated before and after treatment by gamma. It was found that the pH was decline from 6.71 to 5, dissolved oxygen from 2.64 to 0.9 mgL-1 and the total acidity was raised from 0.44 to 0.61 mgL-1. The entirely degradation of Carbaryl takes place at 3.0 kGy and 9.6 mM hydrogen peroxide, H2O2. As a consequence, the possible degradation pathway was suggested.
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