Application of Chemometric Methods in UV-Vis Absorption Spectroscopic Studies of Uranyl Ion Dimerization Reaction in Aqueous Solutions

Factor analysis and self modeling were used as new methodologies to investigate uv-vis absorption spectra of uranyl (0.08 M) aqueous solutions (pH = 3.16, at the ambient temperature) as a function of temperature (8°C-75°C). The study indicated that the above system can be described as a two-component system involving equilibrium between UO₂²⁺ and (UO₂)₂(OH)₂²⁺. The pure spectrum for the dimeric species is extracted from the broad overlapping features via a self-modeling method. In addition, this method allows spectrophotometric determination of the reaction enthalpy for the dimerization reaction.