Effect of temperature on copper, iron and lead leaching from e-waste using citrate solutions

摘要

Highlights•Cu, Fe and Pb extraction from EW-PCB using citrate solutions is temperature dependent.•The initial leaching rate of all three metals increases with temperature.•Above 30 °C, the leaching rates decreases with time due to citrate degradation.•Citrate decomposition could severely impact the process viability.AbstractE-waste is a potential source of large quantities of metals. The ability of citrate solutions to recover base metals from these materials has been demonstrated. In the present study, the effect of the temperature on base metal leaching capacity by the citrate solutions is determined. The material employed consisted of a mechanically prepared, gravity concentrated e-waste, with a metallic content greater than 90%. The leaching conditions were selected based on previous research performed by the authors (0.5 M sodium citrate, pH 4.5 and 20 g per liter e-waste concentrate). Leaching tests were performed at temperatures between 0° and 70 °C. The initial leaching rates for the three metals increased with temperature. However, these tapered off with time for temperatures above 30 °C, which can be associated to citrate destruction.