Degradation of carbofuran by V(IV)/H2O2 system in aqueous solution

Abstract

Carbofuran is a kind of carbamate pesticide commonly used on major crops. The degradation of carbofuran by V (IV)/H₂O₂ system was investigated. The degradation system was strongly influenced by the pH, and initial concentration of VO²⁺. The degradation efficiency of carbofuran at the difference pH with the initial concentration of VO²⁺ in system was observed. An initial carbofuran concentration of 10 mg L¹ was 95% degraded within 10 min at pH 2.6 with original VO²⁺ concentration of 5×10⁴ M. The decrease of TOC content was observed during the catalytic process and the removal percentage was obtained about 20% after 24 h. Furthermore, therefore, this process based on the catalytic reaction of VO²⁺ and VO^{2 +}, and was responsible for the continuous production of hydroxyl radicals in such system. It has also proven that the degradation percentage increase when a little amount of L-ascorbic acid of 5×10⁴ M was applied, the degradation increase up to 20% more at 10 min. A gas chromatography-mass spectrometry analysis showed the formation of seven products, on the basis of formation of time and its abounded, of all these intermediate products, a reaction mechanism path was submitted.

Bangladesh J. Sci. Ind. Res. 50(3), 211-218, 2015