Purification of Yttrium Using Iminodiacetic Acid Resin
Benjamin V. Kronholm and Corby G. Anderson
Summary: A method to separate yttrium from heavy rare earth mixtures
Description: Commercially available chelating ion-exchange resins were applied to the
separation of a mixture of heavy rare earths. Separation coefficients of several rare earths were
calculated based on their degree of adsorption in batch isotherm experiments. Yttrium (Y)
showed particularly high separation coefficients compared to samarium (Sm), europium (Eu),
gadolinium (Gd), terbium (Tb), and dysprosium (Dy), which made up the balance of the mixture
processed. In the treatment of heavy rare earth feed from a known process stream, yttrium
was found to behave similarly to non-ionic components in ion-exclusion chromatography. This
approach could be used to purify yttrium from a mixed solution of “heavy” rare earths without
the use of specialized eluents.
Potential Areas of Application
 Upgrading a yttrium rich mixture
 Separation of yttrium from a mixed rare earth stream.
Main Advantages of this Invention
 Stage efficiency of ion exchange is retained without the complexity of existing ion
exchange techniques
 Takes advantage of the strong selectivity of the iminodiacetic acid functional group with
respect to Yttrium.
Intel ectual Property Status: US utility patent pending (application #14/562,430)
ID number: 14015
Opportunity: We are seeking an exclusive or non-exclusive licensee for implementation of this
For more information contact:
William Vaughan, Director of Technology Transfer
Colorado School of Mines, 1500 Illinois Street, Guggenheim Hall Suite 314, Golden, CO 80401
Phone: 303-384-2555; e-mail: wvaughan@mines.edu