Determination of ¹⁰B/¹¹B in boric acid and B₄C using LA-ICPMS

Abstract

Boron isotopic ratio measurement is very important in the nuclear industry because it is used as neutron poison (in the form of boric acid or a B4C pellet) and control rod material (B4C pellet) in nuclear power plants. Since 10B has a higher neutron absorption cross-section, enriched 10B is used in the nuclear industry and the extent of enrichment varies from 50–90 %. Therefore, it is essential to determine the 10B/11B ratio in boric acid and B4C. The prime purpose of the present study is to utilize LA-ICPMS for evaluating 10B/11B ratio both in solution (boric acid) and solid (B4C pellet) without any pre-treatment so that the difficulty in dissolution or powdering process of B4C (one of the hardest materials) can be avoided and the B4C pellet can be reused. The results obtained from LA-ICPMS for the B4C pellet are discussed and compared with the solution ICPMS, TIMS, and LIMS. The solutions of boric acid (natural abundance) and dissolved B4C (natural & ∼67 % enriched isotopic composition) were analyzed by LA-ICPMS and validated by liquid sampling ICPMS data.