Preliminary Study on Gold Recovery from High Grade E-Waste by Thiourea Leaching and Electrowinning

The present paper is focused on the extraction of gold from high-grade e-waste, i.e., spent electronic connectors and plates, by leaching electrowinning. These are usually made up an alloy covered a layer gold; sometimes, in some them, plastic part also present. applied system consisted acid solution diluted sulfuric (0.2 mol/L) with thiourea (20 g/L) as reagent ferric sulfate (21.8 oxidant. This was three different namely: (1) Connectors partial gold-plated surface (Au concentration—1139 mg/kg); (2) types which completely concentration—590 (3) plates concentration—7900 mg/kg). Gold dissolution yields 52, 94, 49% were achieved first, second, third samples, respectively. About 95% Au recovery after 1.5 h electrowinning at current efficiency only 4.06% consumption 3.02 kWh/kg leach sample.