Catalytic degradation of lindane using gamma radiations: Degradation products

Abstract

Lindane is a concerned pollutant because of its long-term persistence in the environment, potential bio-accumulating characteristic, and associated harms caused to human lives and the environment. Radiolytic degradation of lindane (1.0 mg.L−1) in aqueous phase carried out through gamma (γ) irradiation by 60Co source with 1–12 kGy dose range. The γ-radiation dose optimized and maximum degradation of lindane achieved with 10 kGy at ambient temperature. The catalytical effect of TiO2 and Fe2O3 on degradation efficiency was investigated. The results demonstrate that degradation enhanced with addition of catalyst. The maximum degradation of lindane achieved with TiO2 as compare to Fe2O3. Maximum degradation (%) of lindane was 99% with TiO2; 95% with Fe2O3 and 90.2% without catalyst at 10 kGy dose. Change in concentration of lindane as result of irradiation was verified by HPLC equipped with UV detector. Lindane degradation products extracted and pre-concentrated through Solid Phase Micro-Extraction (SPME) technique. A reaction mechanism envisaged by analyzing the resulting by-products using a Gas Chromatography-Mass Spectrometry (GC–MS) technique. The optimized method applied to industrial wastewater, containing lindane, to evaluate the efficiency of method.