Removal of carbofuran in aqueous solution by using UV-irradiation/hydrogen peroxide

Abstract

Pesticide residues in natural water are one of the biggest environmental problems. carbofuran is an insecticide widely used in agricultural activities and it is easily biodegradable. Although this compound has a relatively short lifetime in soils and its persistence in the environment varies from one to several weeks. For this reason, the elimination of carbofuran residual from contaminated waters using suitable technique is of environmental interest. The aim of this study to investigate the synergetic effect of UV and UV with hydrogen peroxide on the degradation of carbofuran in aqueous solution. 50 mgL−1 aqueous solutions of carbofuran (CBF) were prepared. The solutions were exposed to various UV irradiation times. The irradiation time varied from (15–240 min). Hydrogen peroxide was set at 4.8 mM as a minimum concentration level. To follow the degradation percent, formaldehyde concentration, and to identify the intermediates by-products, GC–MS, IC, and UV–vis spectrophotometer were used. The pH, total acidity, and dissolved oxygen values were determined before and after treatment with UV irradiation with/without hydrogen peroxide. Depending on the results obtained the mechanism pathway (degradation) was suggested. The complete removal of carbofuran in aqueous solution took place at 180 min in the presence of H2O2.