Subtle changes in diglycolamide structure yield large changes in rare earth separation behavior

The separation of adjacent lanthanides continues to be a challenge worldwide, and a grand challenge within CMI in particular, because of the similar physical and chemical properties of these elements and a necessity to advance the use of clean-energy applications. The separation of adjacent lanthanides continues to be a challenge worldwide, and a grand challenge within CMI in particular, because of the similar physical and chemical properties of these elements and a necessity to advance the use of clean-energy applications.
The separation of adjacent lanthanides continues to be a challenge worldwide, and a grand challenge within CMI in particular, because of the similar physical and chemical properties of these elements and a necessity to advance the use of clean-energy applications.
The separation of adjacent lanthanides continues to be a challenge worldwide, and a grand challenge within CMI in particular, because of the similar physical and chemical properties of these elements and a necessity to advance the use of clean-energy applications.

CMI researchers at Idaho National Laboratory and Oak Ridge National Laboratory conducted the research for this highlight

Achievement
An extensive structure-activity study of diglycolamide (DGA) extraction of rare earths reveals a decisive effect of alkyl chain structure.

Significance and impact
New understanding is converging on an ideal structure of DGAs to achieve high selectivity and affinity while allowing high loading and fast phase separation. These improvements will reduce cost and footprint.

Research Details

  • 12 new DGA extractants were synthesized and elucidated through extraction experiments, computations, and solution-structure characterization exploiting DOE user facilities. 
  • Branching of alkyl chains controls the structure of the outer coordination sphere.