This concentrate was then used to evaluate a range of temperatures, leaching reagent and catalyst concentrations, and time for optimal leaching from this e-waste stream (Fig. ). Using this information, a relatively large-scale laboratory leaching and recovery process was then applied on 30.0 g of the powdered e-waste concentrate, containing approximately 3.9 g of gold (Fig. and Fig. ). Accordingly, the powdered ewaste concentrate was combined with TCCA (178 g, 766 mmol), NaBr (2.61 g, 25.5 mmol), and tap water (3.0 L). The leaching was carried out in a 5 L plastic bucket, with mixing provided by an overhead stirrer with a polytetrafluoroethylene (PTFE) coated impeller.