Lixiviants unlock unusual REE leaching patterns from industry feedstock

CMI researchers from Oak Ridge National Laboratory, Ames National Laboratory, and Iowa State University conducted the activity for this highlight

Innovation  
Develop chelators capable of recognizing and leaching REEs from mineral feedstocks based on metal-ion size (large, L; medium, M; small, S).

Achievement

  • Lixiviant 1 selectively leached L > S REEs from RE(OH)3 mining waste concentrate with SFLa/Yb = 114 and SFLa/Y = 146
  • Lixiviant 2 selectively leached S > L REEs with SFYb/La = 601, SFY/La = 177
  • Lixiviant 3 exhibited rare dual-size leaching selectivity for L & S over M REEs

Significance and Impact

  • Leaching selectivity can be tuned by modifying lixiviant structure and thermodynamic affinity.
  • Use of authentic industry samples establishes opportunities for practical application.

Hub Target Addressed  
Rare Earth Elements - Developing processes to recover and separate REEs from traditional or unconventional sources.

image of three bar graphs, which are results of rare earth hydroxide leaching studies