Spectrophotometric determination of chromium in uranium compounds using

The analytical control of several nuclear grade uranium compounds demand the use of very sensible analytical techniques that permit the determination of Cr in uranium compounds was studied. Molecular adsorption spectrometric method for determination of low levels of chromium was used. Ion exchangers procedure (Dowex 1x10) were used for separation of uranium/chromium. The elution of Cr(VI) from the anion exchanger were carried out an solution of [NH4]2 SO4(2,5M)/NH4 OH(1,0M). This procedure measures only hexavalent chromium. The hexavalent chromium is determined colorimetrically by reaction with dipheny carbazide in acid solution. The reaction in very sensitive. The determination limit and detection achieved were 10 ppm and 0,02ug/mL, respectively. The method ius reproducible and sensitive. (author)