Chemical analysis of manganese nodules : Part II. Determination of uranium and thorium after anion-exchange separation |
| |
Authors: | J Korkisch I Steffan G Arrhenius M Fisk J Frazer |
| |
Institution: | Institute for Analytical Chemistry, Analysis of Nuclear Raw Materials Division, University of Vienna, Währingerstrasse 38, A-1090 ViennaAustria;University of California, Scripps Institution of Oceanography, Geological Research Division, La Jolla, California 92037 U.S.A. |
| |
Abstract: | A method is described for the determination of uranium and thorium in manganese nodules. After dissolution of the sample in a mixture of perchloric and hydrofluoric acids, uranium is adsorbed on the strongly basic anion-exchange resin Dowex 1 (chloride form) from 6 M hydrochloric acid. The effluent is evaporated and the residue is taken up in 7 M nitric acid—0.25 M oxalic acid; thorium is then isolated quantitatively by anion-exchange on Dowex 1 (nitrate form). Thorium is eluted with 6 M hydrochloric acid and determined spectrophotometrically by the arsenazo III method. Uranium is eluted from the resin in the chloride form with 1 M hydrochloric acid and then separated from iron, molybdenum and other co-eluted elements on a column of Dowex 1 (chloride form); the medium consists of 50% (v/v) tetrahydrofuran, 40% (v/v) methyl glycol and 10% (vv) 6 M hydrochloric acid. After removal of iron and molybdenum by washing the resin with a mixture of the same composition and with pure aqueous 1 M hydrochloric acid, the adsorbed uranium is eluted with 1 M hydrochloric acid and determined by fluorimetry. The method was used successfully for the determination of ppm-quantities of uranium and thorium in 60 samples of manganese nodules from the Pacific Ocean. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|