Developing a Life Cycle Inventory for Rare Earth Oxides from Ion-Adsorption Deposits: Key Impacts and Further Research Needs
Rare earth production from ion-adsorption deposits constitutes an important rare earth production route, and the most important production route for heavy rare earths such as dysprosium and terbium. The demand for dysprosium has experienced substantial growth in recent years, mainly due to its use in neodymium-iron-boron (Nd-Fe-B) magnets, the demand for which is increasing largely due to their use in efficient motor applications. Hence, the analysis of environmental impacts associated with rare earth mining and processing is gaining importance. In this study, a life cycle inventory for rare earth production from ion-adsorption deposits was compiled through a detailed analysis of the literature and with help from industry experts. A detailed review of the literature on environmental impacts associated with the mining process was also conducted, and impacts not covered by the current impact assessment methods are discussed. Despite the detailed study, data uncertainties remain. Therefore, recommendations for further research are given, including further investigations into the fate of emissions from in situ leaching of rare earths in the proximity of the mining site, and development of the methods used to assess resource extraction.