Investigation into the effect of pH on lanthanide separation using α-hydroxyisobutyric acid

SCK•CEN Mentor

Burgoyne Andrew, aburgoyn@sckcen.be, +32 (0)14 33 82 15

Expert group

Radiochemistry

SCK•CEN Co-mentor

Van Hoecke Karen , kvhoecke@sckcen.be , +32 (0)14 33 82 01

Introduction

Rare earth elements are important for many scientific applications. The purity and separation of lanthanides is very important for these technologies. Cation exchangers and elution by complexing agents are commonly used for the separation of lanthanides by the use of ion exchange methods. Within the group of hydroxyacids, α-hydroxyisobutyric acid (α-HIBA), is used as an eluent and is one of the most favourable eluents in this group. α-HIBA, buffered with ammonium hydroxide (NH4OH), results in good separation of dysprosium(III) (Dy), terbium(III) (Tb) and gadolinium(III) (Gd) and can be used at room temperature. Simply increasing the concentration of α-HIBA gives elution of the lanthanides, but little is know about the effect of the pH of the eluent.

Objective

The main objective is to investigate the effect of pH on the retention times of lanthanides using α-HIBA and NH4OH. This will be acheived by:

  • Performing calculations and preparating buffered solutions of known concentrations and pH using α-HIBA and NH4OH
  • Performing standardized titrations of the α-HIBA and NH4OH solutions
  • Confirming titration results by the use of a pH meter
  • Analysis of data obtained from lanthanide separation using the prepared solutions

The minimum diploma level of the candidate needs to be

A3: Lower secondary education

The candidate needs to have a background in

Chemistry

Estimated duration

2 weeks