Improvements on high-precision measurement of bromine isotope ratios by multicollector inductively coupled plasma mass spectrometry

A simple distillation method to extract bromine from natural water and salt samples for isotope analysis by multi‐collector inductively coupled plasma mass spectrometry

“…The vapour is collected in an NH 3 solution at 0.5 N. The final solution is ideally 0.2 N NH 4 NO 3 at pH 8–9. The method has, however, been tested over a range of NH 4 NO 3 concentrations (0.15 to 0.35 N) and pH values (1 to 9) without any distinguishable effect on the δ 81 Br values that were measured (within 1 σ of 0.1‰). Despite the low distillation yield, as the oxidation reaction is instantaneous and occurs without isotope fractionation, it is possible to use the proposed technique to extract Br while Cl is only poorly distilled in 10 min.…”

“…However due to the high first ionisation energy of Br and to the interference of Ar 2 H + with 81 Br + in ICP‐MS, a fairly high minimum concentration of Br − still needs to be present in the sample solution that is fed into the mass spectrometer. Although high‐resolution techniques have been developed, the intrinsic instrumental mass drift of MC‐ICP‐MS can generate inaccurate measurements, due to the reduced width of the Br + plateau in high‐resolution mode, making low‐resolution measurements a more robust method . This Ar 2 H + interference is avoided when Br isotopes are measured by thermal ionisation mass spectrometry (TIMS) in the form of Cs 2 Br + ions .…”

“…In order to be able to measure Br stable isotope ratios in smaller samples, various multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) methods have been developed in recent years to measure Br isotopes in natural water samples. [6][7][8][9][10] However due to the high first ionisation energy of Br and to the interference of Ar 2 H + with 81 Br + in ICP-MS, a fairly high minimum concentration of Br − still needs to be present in the sample solution that is fed into the mass spectrometer.…”

“…Although high-resolution techniques have been developed, 8 the intrinsic instrumental mass drift of MC-ICP-MS can generate inaccurate measurements, due to the reduced width of the Br + plateau in highresolution mode, making low-resolution measurements a more robust method. 9 This Ar 2 H + interference is avoided when Br isotopes are measured by thermal ionisation mass spectrometry (TIMS) in the form of Cs 2 Br + ions.…”

Application of non-traditional stable isotopes in analytical ecogeochemistry assessed by MC ICP-MS - A critical review

“…Wei et al presented recently an improved analytical method for the determination of Br isotope ratios for the application to trace Br in its geochemical cycle, pointing to a future project dedicated to study the processes of ore genesis of rare and dispersed mineral deposits in western China [130].…”