Removal of Toxic Metal Ions from Sungun Acid Rock Drainage Using Mordenite Zeolite, Graphene Nanosheets, and a Novel Metal-Organic Framework

We evaluated the sorptive properties of mordenite zeolite (MOR), a copper terephthalate metal-organic framework (MOF), and graphene oxide (GO) and their potential use in treating acid rock drainage (ARD) containing Fe3+, Cu2+, Mn2+, Zn2+, Pb2+, and Cd2+ ions. MOR was prepared via a hydrothermal method, MOF was prepared via a solvothermal method, and few-layered GO nanosheets were synthesized using Hummers' method. The aqueous contaminants were removed by chemico-physical sorption and ion exchange in batch tests. It proved possible to dramatically improve removal efficiency and sorptive capacity by optimizing experimental conditions. Magnetic MOF crystals were more efficient in removing metals than the MOR and GO. Sorption tests using ARD from the Sungun copper mine and a multi-component solution containing cationic metal species revealed that both GO nanosheets and magnetic MOF have great potential for ARD treatment.