AUTHOR=Lee Seung-Gu , Ko Kyung-Seok 

TITLE=Development of an analytical method for accurate and precise determination of rare earth element concentrations in geological materials using an MC-ICP-MS and group separation

JOURNAL=Frontiers in Chemistry

VOLUME=Volume 10 - 2022

YEAR=2023

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2022.906160

DOI=10.3389/fchem.2022.906160

ISSN=2296-2646

ABSTRACT=Concentration of rare earth elements (REEs) in geological materials including SLRS-6 natural water Certified Reference Material and JB1b, JA1 and JG2 Standard Rock Materials can be used as a tracer to characterize various geochemical processes in Earth systems. Particularly, accurate and precise determination of rare earth element concentration in natural waters is difficult due to their extremely low concentration and the interference of polyatomic oxides. In this study, we developed a method for accurate and precise determination of the REE (particularly, heavy rare earth elements) concentrations in geological materials including natural waters using a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) and group separation by 2-hydroxyisobutyric acid (HIBA). The REEs were separated into light rare earth elements (LREE, La-Ce-Pr-Nd), middle rare earth elements (MREE, Sm-Eu-Gd-Tb) and heavy rare earth elements (HREE, Dy- Ho-Er-Tm-Yb-Lu) by a cation exchange column (AG50W-X8 200–400 mesh) using HIBA. The recovery rates of each REE in natural water sample exceeded 98%, whereas the recovery rates of each REE in rock materials exceeded 95% except HREE. The method developed in this study can accurately measure the REE concentrations (particularly, HREE) in geological materials without polyatomic oxide interference during the REE analysis by MC-ICP-MS, and thus can correctly interpret the geochemical implications of REEs in geological system. The determination of Sr concentration and Sr isotopic ratio of SLRS-6 CRM and JB1b, JA1 and JG2 SRMs are also reported and show good agreement with recommended value.