On-line speciation of uranyl chelates in supercritical CO2 by time-resolved laser-induced fluorescence spectroscopy

The dynamic emission characteristics of selected uranyl complexes in supercritical (ScF) CO2 have been quantified with time-resolved laser-induced fluorescence (TRLIF). A variety of factors were found to affect the emission from uranyl complexes in ScF including ligand, adduct, pressure, and temperature. TRLIF was shown to allow on-line speciation and quantitative analysis of uranyl complexes with different primary ligands in ScF CO2. The method was applied to real-time analysis of multiligand uranium extractions from aqueous solutions with ScF CO2.