O01_P03

Comparison of two ¹⁰Be purification methods for AMS measurement

Loftfield J¹, Lachner J², Malter M¹, Stübner K², Adolphi F¹

¹Alfred Wegener Institute, Bremerhaven, Germany, ²Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany

The cosmogenic radionuclide ¹⁰Be is a powerful tool in paleosciences. Its applications include the dating of rocks and sediments, reconstruction of past changes in solar activity and the geomagnetic field strength, and the synchronization of climate archives.

However, sample preparation and especially purification of Beryllium from environmental samples can be time consuming and expensive. Typically, purification of sediment samples is achieved by a combination of hydroxide precipitations and ion exchange chromatography. Here, we test a method of successive hydroxide precipitations at different pH-values in combination with precipitation in NaHCO₃, to purify samples of marine sediments from the Norwegian Sea and the Lomonosov Ridge for ¹⁰Be-analysis. We compare the performance of this method to an ion chromatography-based method (Simon et al., 2016) with respect to the Beryllium yield, purity of the resulting Be(OH)₂, blank, and performance in the AMS for both protocols. We discuss the advantages and challenges of the protocols, their applicability, and their capacity in terms of sample throughput.

Simon, Q., Thouveny, N., Bourlès, D. L., Nuttin, L., Hillaire-Marcel, C., & St-Onge, G. (2016). Authigenic ¹⁰Be/⁹Be ratios and ¹⁰Be-fluxes (230Thxs-normalized) in central Baffin Bay sediments during the last glacial cycle: Paleoenvironmental implications. Quaternary Science Reviews, 140, 142–162. https://doi.org/10.1016/j.quascirev.2016.03.027