Recovery of Rare Earth Elements from the Ferrous Fraction of Electronic Waste

Abstract

Rare Earth Elements (REEs) have unique properties that have led to a rapid increase of consumption in modern technological products. This has in turn led to a greater awareness of the limited and highly localized nature of mineral reserves, and the dilute nature of the undeveloped resources including those from secondary sources.

Recycling of REEs is seen as one possible way to increase the supply of these elements with less impact on the environment than extraction from ores. In the present recycling processes for electronic waste these elements are, however, largely oxidized and diluted into discarded streams making recycling a challenging task.

Selected industrial ferrous streams of electronic waste that contain significant amounts of NdFeB magnets were investigated in the present work. Highly reducing conditions and high temperature were applied to obtain a slag containing only the most stable oxides, which also proved to include very high concentrations of REEs.