Supergravity separation for recovering Pb and Sn from electronic waste

Electronic waste (e-waste) contains plenty of toxic substances as well as valuable metals (e.g. Pb and Sn). The storage of e-waste presents a long-term environmental issue but also an opportunity to recover valuable metals. Supergravity as a novel technology was used to separate and recover Pb-Sn alloy from e-waste in this study. Based on the different melting points of various metals, it can separate Pb and Sn from e-waste by melt separation in a supergravity field produced by a centrifugal apparatus. Several parameters affecting the recovery of Pb and Sn were investigated. Under optimal conditions including a gravity coefficient of 1000, centrifugal time of 5 min, and temperature of 410 °C, the recovery values of Pb and Sn were 54.41% and 41.94%, respectively. The (Pb + Sn)% of Pb-Sn alloy was 94.84 wt.% and the mass ratio of Pb/Sn was 0.66. This Pb-Sn alloy was suitable as raw materials for industrial applications. Some solid solutions were formed with Sn may be the main reason for the low recovery of Sn.