A method has been developed that uses uranium hexafluoride as the
internal standard to quantitatively determine trace impurities in the
uranium hexafluoride using relative response factors. A computer
program was written to control the mass spectrometer and determine
the concentrations of target impurities present. Overlapping spectra are
deconvoluted using the Gauss-Seidel iterative method. The composition
of the sample is determined by comparing the peak height ratios of the
target impurities to the internal standard.
Measurement parameters are easily modified using the menu driven
program. A flexible database allows the list of target impurities to be
extended to accommodate any changes in analytical requirements. The
method has been adapted for automatic on-line measurements.
The technique was evaluated by analysing a number of carefully
prepared standards. Nine target impurities were studied which ranged
in concentration from parts per million to percentages. An overall
precision of fifteen percent was obtained.