Optimized chemical separation and measurement by TE TIMS using carburized filaments for uranium isotope ratio measurements applied to plutonium chronometry

An optimized method is described for U/Pu separation and subsequent measurement of the amount contents of uranium isotopes by total evaporation TIMS with a double filament setup combined with filament carburization for age de-termination of plutonium samples. The use of carburized filaments improved the signal behavior for total evaporation TIMS measurements of uranium. Signal peaks at the start of the measurement resulting from material deposited on the filament by the separation procedure were avoided. Hence, loss of sample before the actual TE data acquisition was prevented and automated measurement sequences could be accomplished. Furthermore, separation of residual plutonium in the separated uranium fraction was achieved directly on the filament by use of the carburized filaments. Although the analytical approach was originally tailored to achieve reliable results only for the 238Pu/234U, 239Pu/235U, and 240Pu/236U chronometers, the optimization of the procedure additionally allowed the use of the 242Pu/238U isotope amount ratio as a highly sensitive indicator for residual non-radiogenic uranium in the plutonium sample. The sample preparation method described in this article has been successfully applied for the age determination of CRM NBS 947 and other sulfate and oxide plutonium samples.

STURM M.;  RICHTER Stephan;  AREGBE Yetunde;  WELLUM R.;  PROHASKA Thomas; 

2016-11-17

SPRINGER HEIDELBERG

JRC97513

1618-2642,   

http://pubs.acs.org/doi/abs/10.1021/acs.analchem.5b03852,    https://publications.jrc.ec.europa.eu/repository/handle/JRC97513,   

10.1021/acs.analchem.5b03852,