Zirconium and Hafnium Separation by Novel Green Emulsion Liquid Membrane Containing an Environmentally Benign Diluent

Abstract

Green liquid emulsion membrane (LEM) was developed for separation of zirconium and hafnium from nitric acid medium. The membrane is based on the use of CYANEX-272 diluted with corn oil (green diluent) as a carrier, span 80 as a surfactant and citric acid as a stripping agent. The factors affecting the stability of the LEM were investigated under chosen conditions. The parameters affecting the permeation of Zr and Hf from nitrate medium were also studied. The metal ion content in the inner phase obtained by demulsifying the loaded CC-LEM using the freeze-thaw method is 22.8 g/l Zr and 2.05 mg/l Hf i.e. the contamination of the recovered Zr is 89.91 mg Hf/ kg Zr which is below the limit for the use of zirconium in nuclear applications.