Rare earth elements in sedimentary phosphate deposits: Solution to the global REE crisis?

Gondwana Research
By: , and 

Links

Abstract

The critical role of rare earth elements (REEs), particularly heavy REEs (HREEs), in high-tech industries has created a surge in demand that is quickly outstripping known global supply and has triggered a worldwide scramble to discover new sources. The chemical analysis of 23 sedimentary phosphate deposits (phosphorites) in the United States demonstrates that they are significantly enriched in REEs. Leaching experiments using dilute H2SO4 and HCl, extracted nearly 100% of their total REE content and show that the extraction of REEs from phosphorites is not subject to the many technological and environmental challenges that vex the exploitation of many identified REE deposits. Our data suggest that phosphate rock currently mined in the United States has the potential to produce a significant proportion of the world's REE demand as a byproduct. Importantly, the size and concentration of HREEs in some unmined phosphorites dwarf the world's richest REE deposits. Secular variation in phosphate REE contents identifies geologic time periods favorable for the formation of currently unrecognized high-REE phosphates. The extraordinary endowment, combined with the ease of REE extraction, indicates that such phosphorites might be considered as a primary source of REEs with the potential to resolve the global REE (particularly for HREE) supply shortage.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Rare earth elements in sedimentary phosphate deposits: Solution to the global REE crisis?
Series title Gondwana Research
DOI 10.1016/j.gr.2014.10.008
Volume 27
Issue 2
Year Published 2015
Language English
Publisher Elsevier
Contributing office(s) Central Mineral and Environmental Resources Science Center
Description 10 p.
First page 776
Last page 785