Determination of rubidium, strontium and barium in barite by atomic-absorption spectrometry after dissolution in disodium ethylenediaminetetra-acetate.
A simple and rapid method is described for determining up to 50% of barium, approximately 350 mug/g or more of strontium and approximately 1 mug/g or more of rubidium in barite samples. The method involves dissolution of the barite by refluxing with an ammoniacal disodium EDTA solution. For the determination of total strontium and rubidium, the silicate residue remaining is filtered off and decomposed with hydrofluoric and sulphuric acids to recover residual strontium and rubidium. Barium and strontium are subsequently determined by flame atomic-absorption spectrometry and rubidium is determined by graphite-furnace atomic-absorption spectrometry. Results obtained for barium and strontium in several barites by the proposed method are compared with those obtained by wavelength-dispersive and energy-dispersive X-ray fluorescence spectrometry, respectively. The method is reliable and more rapid than conventional methods.
Gupta
J G
JG
Geological Survey of Canada, Ottawa, Ontario, Canada.