Determination of rare earth elements and yttrium in zircons by plasma emission spectrometry after solvent extraction separation of zirconium with di-(2ethylhexyl)phosphoric acid

摘要

A simple and rapid inductively coupled plasma optical emission spectrometric (ICP-OES) determination of trace ievel rare eartb elements (REEs) and Y in high purity zirconium matrix and zircon samples is described. The method involves solvent extraction separation of zirconium from 3 M HC1 solution using di-(2-ethylhexyl)phosphoric acid (D2EHPA) in toluene, which selectively separates zirconium leaving behind the trace REEs and Y in aqueous media, for quantification by ICP-OES. The quantitative extraction of Tm, Yb and Lu are achieved by the addition of octanol. The method has been applied to synthetic zirconium samples doped with REEs and Y and the recoveries were quantitative. The method was extended to the determination of REEs and Y zircon samples. Accuracy of the method was checked by applying the proposed method to three zircon certified reference materials and the percentage error obtained was 1-6%. The values obtained agreed well with the reported values. The percentage RSD of ail estimated elements varied between 1-5% at different concentration levels.