A spectrographic method of rhenium determination in uranium ores

A method of direct determining rhenium in uranium ores has been elaborated. Copper oxide added to the ore in the quanity of 5% was applied as thermochemical agent. The samples were made into pellets and were excited in a 9 A d.c. arc from the crater of a graphite anode. Rhenium is volatilised completely and excited within the first 15 seconds of arcing. On the other hand, manganese and chromium are excited in a next phase of arcing, thus making possible rhenium determination. The spectra were recorded on a grating spectrograph of high dispersion PGS-2 in the second order, exposure time 15 seconds. The middle part of Re 346.046 nm line was measured in respect to the background. The method elaborated makes possible to determine rhenium from 0.3 to 30 ppm in ores containing not more than 0.1% of Mo or Cr and 0.2% of Mn. The relative error of determination of trace quantities from 0.3 to 30 ppm of rhenium amounts to about 50%. (author)