Separation of Zr from Hf in Hydrochloric Acid Solution Using Amine-Based Extractants

Abstract

Liquid–liquid extraction studies have been performed to investigate the selective extraction of zirconium (Zr) and hafnium (Hf) in hydrochloric acid medium. For this purpose, several amine-based extractants were used at varying concentrations of extractants and HCl. Among the tested extractants, Alamine 336 showed good selectivity for Zr over Hf and led to the highest separation factor. A McCabe–Thiele diagram was constructed for the extraction of Zr with Alamine 336 in kerosene, and the tested batch simulation of counter-current extraction studies showed that the extractions of Zr and Hf impurities were 98.5% and 12.5%, respectively. The coextracted Hf was scrubbed with dilute H2SO4 solution, and complete stripping of Zr was successfully achieved from the loaded organic phase by simple contact with 1 M HCl solution.