Gamma irradiation-induced Cd2+ and Pb2+ removal from different kinds of water

Gamma irradiation-induced removal of cadmium ion (Cd2+) and lead ion (Pb2+) in different kinds of water was investigated. It is observed that solution pH, dissolved oxygen (DO) concentration, sodium carbonate and EDTA played an important effect on Cd2+ and Pb2+ removal. Low solution pH, low DO concentration and sodium carbonate were favorable for removal of Cd2+ and Pb2+ by reducing species, while the presence of EDTA in solution restrained Cd2+ and Pb2+ reduction. Pb2+ removal percentage was higher compared to that of Cd2+ at the same experimental conditions. Cd2+ and Pb2+ removal under different conditions was well described by the pseudo-first-order kinetics model. Cd2+ and Pb2+ removal in different water followed an increasing order: water inflow < surface water < effluent < ground water. In addition, gamma irradiation resulted in a slight decrease in pH and TOC values of water inflow of municipal sewage treatment plant. (C) 2008 Elsevier Ltd. All rights reserved.