A Feasibility Study on Chemical Separation of Pb, Sr and Nd from the Same Single Dissolution of Geological Sample

Two individual solutions were required by the traditional chemical separation procedures to separate Pb and Sr-Nd, however, it was difficult for limited geological samples. In this study, we presented an improved chemical method for Pb, Sr and Nd separation from the same single dissolution. The procedure consisted of the following two steps: (1) the sample was digested with HNO₃-HF-HClO₄ mixed acids. (2) Pb, Sr and Nd were separated from the matrix by a combination of AG1-X8, AG50W-X8 and HDEHP ion exchange columns. The recoveries of the samples were better than 95%. The total procedural blanks measured for Pb, Sr, and Nd were lower than 0.2 ng, 1.5 ng and 1.1 ng, respectively. Analytical feasibility, flexibility and reproducibility of Pb, Sr and Nd isotope were verified by USGS rock standards of AGV-2 and BHVO-2. The isotopic compositions of Pb, Sr and Nd were measured by Multi-Collector Inductively Coupled Plasma-Mass Spectrometry (MC-ICP-MS). The results were consistent of the improved method and the traditional chemical procedures within the uncertainties. It indicated that the presented technique has great potential application of Pb, Sr and Nd isotopic measurements for limited or rare geological rocks.