The Effect of Eluent Concentration on the Separation of Nd with Ln-resin Method

Abstract

The rare earth element(REE)s play an important role in understanding of rock formation and evolution because of their similar geochemical behaviors. Sm and Nd are more useful than other REEs because Sm-Nd isotopic system has important applications for geochemical interpretation like age dating and crustal evolution. These studies require a chromatographic technique for Sm and Nd separation from the geological samples. Ln-resin method using 0.25 M HCl as the eluent is widely used for Nd separation. However, this technique has a disadvantage of the poor elemental selectivity that the Nd fraction contains Ce as a tailing of the previous fraction. This technical report is a comparison study on the effect of eluent concentration between 0.25 M HCl and 0.15 M HCl on the separation of Nd with Ln-resin method for improving the technique of Nd separation. The results showed that the separation of Ce and Nd using 0.15 M HCl as the eluent was not effective compared to the separation using 0.25 M HCl. In this experiment, we could confirm that the dilution of eluent might not be effective on the high purity separation of Nd with Ln-resin method.

Determination of Sr–Nd–Pb Isotopic Ratios of Rock Reference Materials Using Column Separation Techniques and TIMS

“…During the separation protocol, there were elution overlaps between Sr and Rb and between Nd and Ce (see Figure I-4 from [44] and Figure 4 from [45]), but no overlap was found between Sr, Nd, and Pb. Because of the peak overlapping and tailing, the Sr and Nd solutions had isobaric interferences such as 87 Rb and 143 (CeH) + [38][39][40]50].…”

“…Before TIMS analysis, samples must be purified through ion-exchange. Table 1 presented the modified separation conditions of Sr and Nd from [44,45]. Before loading the sample solutions, the column and resin were pre-cleaned twice with 4 mL of 2.5 M HCl.…”

“…Finally, the REEs fraction was collected in 10 mL of 6 M HCl. To separate Nd using the Ln resin method [45], a sample solution including REEs was prepared by keeping the samples in 0.2 mL of 0.25 M HCl. A quartz-glass column was pre-cleaned with 4 mL 0.25 M HCl and packed with 2 mL of Ln (HDEHP) resin, after which the sample solution was passed through the column.…”