Anion-exchange polymer filament coating for ultra-trace isotopic analysis of plutonium by thermal ionization mass spectrometry

TALANTA

卷:189

Article

Mannion, Joseph M.¹  Shick, Charles R., Jr.²  Fugate, Glenn A.^2,4  Powell, Brian A.³  Husson, Scott M.¹ 

[1] Clemson Univ, Dept Chem & Biomol Engn, 127 Earle Hall, Clemson, SC 29634 USA

[2] Natl Secur Directorate, Savannah River Natl Lab, Bldg 703-43A Room 18-7, Aiken, SC 29808 USA

[3] Clemson Univ, Dept Environm Engn & Earth Sci, 342 Comp Court, Anderson, SC 29625 USA

[4] Oak Ridge Natl Lab, Nucl Secur & Isotope Technol Div, Oak Ridge, TN 37831 USA

关键词: Actinide isotope ratio measurements;    Environmental monitoring;    Nonproliferation;    Nuclear forensics;    Ultra-trace analysis;   

DOI  :  10.1016/j.talanta.2018.07.048

来源: Elsevier

【 摘 要 】

A new sample loading procedure was developed for isotope measurements of ultra-trace amounts of Pu with thermal ionization mass spectrometry (TIMS) that is based on a polymer thin film architecture. The goals were to simplify single filament TIMS sample preparation for Pu, while preserving the sensitivity and accuracy of the resin bead loading method, and to eliminate sample losses experienced with the bead loading method. Rhenium filaments were degassed, dip-coated with a thin (similar to 120 nm) hydrophobic base layer of poly(vinylbenzyl chloride) (PVBC), and spotted with an aqueous solution comprising triethylamine-quaternized PVBC and diazabicyclo[2.2.2]octane crosslinker. This procedure formed a toroidal, hydrophilic anion-exchange polymer spot surrounded by the hydrophobic base polymer. The thin film-coated filaments were direct loaded with 10 pg of New Brunswick Laboratory certified reference material (NBL CRM) 128 from a 9 M HCl matrix. Aqueous sample droplets adhered to the anion-exchange polymer spot, facilitating sample loading. Toroidal spots with a thickness of 20-30 gm generated the highest sample utilization, surpassing the sample utilization of the standard bead loading method by 175%. Measured isotopic ratios were in good agreement with the certified value of the Pu-239/Pu-242 ratio for NBL CRM 128. The use of dimpled filaments further aided sample loading by providing a well-shaped substrate to deposit the sample droplet. No sample losses were experienced with the thin film loading method over 65 sample analyses. Finally, polymer coatings suppressed filament aging under atmospheric conditions, enabling the bulk production of filaments with adequate shelf life for future analyses.

【 授权许可】

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