Wavelength-dispersive x-ray fluorescence spectrometric determination of cadmium in zinc ores

Zinc ores are known to contain significant amounts of cadmium. The paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence spectrometric technique for determining cadmium in zinc ores. The technique uses a sequential x-ray fluorescence spectrometer, 100 kV – 80 mA – 3kW x-ray generator, tungsten x-ray tube, LiF 220 analysing crystal, fine (150 μm) collimator, air path, scintillation counter, and short counting times.

The accuracy of the technique is excellent (within 2 percent). The precision is also excellent (within 2 percent). The lower limit of detection is 3 ppm. The time taken for determining cadmium in a batch of twentyfour samples of zinc ores, for a replication of four analyses per sample, by one operator, using a manual wavelength-dispersive x-ray fluorescence spectrometer, is only eight hours.