DETERMINATION OF URANIUM IN SOLUTION AT THE NG-1-1 LEVEL BY TIME-RESOLVED LASER-INDUCED SPECTROFLUORIMETRY - APPLICATION TO GEOLOGICAL SAMPLES

Time-resolved laser-induced spectrofluorimetry was used for the determination of uranium at the ng 1-1 level in alkaline water with high chloride and sulphide contents in order to obtain a better understanding of uranium mobilization under natural reducing conditions. The optimum complexing medium, limit of detection and results obtained for several waters from different localities in the Pyrenees are presented. These data seem to confirm that even at very low uranium concentrations, thermodynamic control by a mineral phase takes place. © 1990.