Selective Separation-Flotation of Hafnium from Zirconium and Their Determination in Real Samples

Abstract

A simple procedure is presented for selective separation of hafnium from zirconium in both simulated and real samples. The procedure depends on using Alizarin Red sulfonate (ARS) for complexation of both Hf(IV) and Zr(IV), in which a flotation step is applied for floating their complexes using oleic acid (HOL) surfactant. Several factors affecting the flotation process have been studied. It is found that hydrogen ion concentration is of paramount importance. Maximum separation of Zr(IV) (100%) is achieved at pH range 1.5 - 2, whereas at pH range 5.5 - 7 Hf(IV) is completely separated. Interference of various foreign ions is avoided by adding excess ARS. Infra-red data were used for suggesting the flotation mechanism.