Uranium(VI) speciation in natural waters determined by TRLFS

Time-resolved Laser-induced Fluorescence Spectroscopy (TRLFS) is a very helpful tool with an extremely low detection limit for analyzing speciation of certain radioactive heavy metal ions like uranium (VI). Thus this technique is preferential appropriate for detection of speciation from that ions in environmental relevant concentrations. So TRLFS can be useful in safety assessment concerning migration behaviour of radioactive elements.
In this presentation is shown, that the uranium speciation in natural occurring seepage water samples, and in soil water samples, all samples collected from test site “Gessenwiese” close to Ronneburg in Eastern Thuringia (Germany), were analyzed by TRLFS. This test site was installed as a part of a research program of the Friedrich Schiller University Jena for investigations within the area of recultivated former uranium mining heaps.
The TRLFS measurements on water samples collected within test site Gessenwiese revealed that the uranium speciation in that seepage water is dominated by the hydrolyzed and monomer uranium (VI) sulfate species UO2SO4(aq). This results presented here are a convincing example for the suitability of TRFLS in analyzing the speciation of uranium from natural occurring water samples with pH values between 3.2 and 4.0.