日本質量分析学会 第69回質量分析総合討論会会

演題概要

オーラルセッション

第2日 5月20日(木) 11:00~11:20 C会場(Zoom)

小惑星サンプルリターン試料のマルチ同位体分析

(1東工大2東大院理)
o横山哲也1Gautam, Ikshu1大熊悠介1飯塚毅2

The sample-return mission Hayabusa2 conducted two sampling sequences that collected ~5 g of the surface and sub-surface materials from a C-type asteroid, Ryugu in 2019. To characterize the collected asteroidal materials, we have developed a technique for a multi-isotopic analysis that uses ~ 30 mg of the Ryugu sample. Two terrestrial basalts and two CM chondrites were chosen as the analog samples to evaluate the performance of the developed technique. The powdered sample was decomposed by a mixture of HF + HNO3 in a Teflon vessel. The sample was conditioned with HBr for the separation of Pb by anion exchange chromatography (AG1-X8), followed by the separation of Ti+Zr+Hf, W, and Mo by AG1-X8, Fe and U by AG1-X8, Sr and Ba by Sr Resin, REEs by RE Resin, Ca by DGA-n Resin, Cr by 1:1 mixture of AG50W-X8 and AG50W-X12, and Mg and Ni by Ni Resin. The recovery yields of individual target elements are generally >90% during each step of the chromatography. The isotopic compositions of the analog samples, especially for Cr and Ti, will be reported in the presentation.