The stable domestic supply of gallium (Ga), indium (In) and germanium (Ge) has been identified as a critical need for the United States. Electric arc furnace (EAF) dusts processed to recover zinc produce a process residue that could be a potential source of these critical materials. For this study, an industrial zinc leach residue was characterized to determine the predominant mineral phases and leached with common mineral acids. Atmospheric agitated leaching using sulfuric acid and hydrochloric acid were examined to determine the extractions of gallium, indium and germanium as a function of concentration and temperature. Extractions of gallium were found to be similar to iron in all experiments. The maximum percentage of gallium, indium and germanium leached into solution were 71 percent, 63 percent and 48 percent, respectively.
