Metal Removal from Synthetic Mine Tailing Leachates using Fixed-Bed Ion-Exchange Columns

The generation and disposal of solid wastes from the mining industry has the potential to cause significant, enduring environmental damage. Atmospheric weathering of waste stockpiles leads to the formation of metal-rich leachates, which have been shown to adversely affect ecological communities, and can act as barriers towards meeting legislative water quality targets. The removal of problematic metals from tailings prior to disposal may pose an opportunity to prevent this damage. This research presents results from dynamic column experiments aimed at assessing the performance of several commercial ion-exchange resins for metal removal from simulated tailing leachates. Artificial mixed-metal solutions were prepared to simulate the conditions expected following a sulphuric acid leach of mine tailings. Metal breakthrough from each column was modelled to gain an insight to the selectivity and capacity of each tested resin, allowing identification of the most-suitable resins to take forward to process optimisation and scale-up.