Chromatographic Separation of Americium(III) from Europium(III) Using Alkyl Diglycolamic Acid

Abstract

The alkyl derivatives of diglycolamic acid (DGAA) (alkyl = butyl to decyl) were synthesized and characterized by ¹H and ¹³C nmr, and IR spectroscopy. The diglycolamic acids were impregnated in Tulsion ADS 400 for the chromatographic separation of hazardous Am(III) and Eu(III). The extraction behavior of Am(III) and Eu(III) in the impregnated resin was studied as a function of various parameters such as aqueous phase pH, concentration of DGAA, and diethylenetriaminepentaacetic acid (DTPA), etc. The distribution coefficient (K_d) of Am(III) and Eu(III) in the resin phase increased with increase in pH of aqueous phase and loading of DGAA in the resin. The concentration of DTPA needed for efficient separation of Am(III) from Eu(III) was optimized and the performance of the resin under dynamic extraction conditions was assessed by following the breakthrough curve in the column study using octyl derivative of DGAA. The conditions needed for the elution of Am(III) alone from the column was performed using 0.001 M DTPA solution at pH 2.5. The study confirmed the feasibility of separating Am(III) from Eu(III) using octyl-DGAA by extraction chromatography.

Keywords:

• extraction chromatography
• europium(III)
• americium(III)
• diglycolamic acid
• distribution coefficient

ACKNOWLEDGEMENTS

The authors would like to thank SAIF, IIT Madras for analyzing the NMR spectra and Project students Ms. Sunitha, PSG, College of Technology, Coimbatore, and Ms. Soumya, Calicut University, for their help during the experiments. The authors are also thankful to Mrs. Amuda Suba for her kind help.