Recovery of uranium, hafnium and zirconium from petroleum ash leach liquor

Abstract

We investigated the optimum adsorption conditions of uranium, hafnium and zirconium elements from petroleum fly ash leach liquor using Dowex 1×8 as a strong basic anion exchange. Uranium was precipitated from the acidic solution by adding either NaOH or H₂O₂ solutions at different pH. The remaining concentrate containing hafnium and zirconium was firstly precipitated by using NaOH solution followed by dissolution in HCl solution and individually separated from each other by a solvent extraction technique using Alamine 336 as the extractant. On the other hand, the loaded zirconium was stripped with HCl while hafnium was scrubbed by using H₂SO₄ acid.