Concomitant separation of strontium and samarium-neodymium for isotopic analysis in silicate samples, based on specific extraction chromatography

A separation scheme for strontium and light rare earth elements and its application to the isotopic analysis of strontium and neodymium in silicate rocks are presented. This method benefits from the selectivity and high capacity of two newly introduced extraction Chromatographic materials, referred to as Sr.Spec and TRU.Spec, respectively. These afford a straightforward separation of Sr and Sm + Nd with high yield, good purity and satisfactory blank levels, on very small (0.25 ml) columns using small volumes of solutions of a single mineral acid, HNO3. The validity of the method is illustrated by the measurement of 87Sr/ 86Sr and 143Nd/144Nd ratios in twelve international standard reference materials.