PACKED-COLUMN SUPERCRITICAL-FLUID CHROMATOGRAPHY - QUANTITATIVE-DETERMINATION OF URANIUM WITHOUT LIQUID WASTE GENERATION

A new procedure for the determination of uranium by packed-column supe rcritical fluid chromatography is proposed. A nonfluorinated chelating agent selective for copper and uranium, the 2,6-diacetylpyridin bis(b enzoylhydrazone), has been chosen, We have studied its chromatographic properties on different stationary phases and the influence of the me thanol content in the carbon dioxide mobile phase, The separation of t he metal compounds was conducted with and without solvent injection, A calibration curve was obtained for uranium in the range of 52-323 ng injected, The accuracy of the method is 0.5%,;the repeatability 4%. Th e same studies were performed with a new compound, diacetyl-2,6 pyridi ne bis(4-tert-butyl benzoylhydrazone). An increase in retention and ef ficiency was then observed.