Most of the studies on sorption processes take into account only a
ihcrmodynamic approach, and only lew studies have paid attention to ihc
structural aspect (i.e. structure of ihc postulated surface complex).
Experiments were conducted to study UO22+ sorption onto zirconium and thorium phosphate surfaces.
Moreover, in order to identify the nature of the sorption sites and the
structure of the surface complex, various spectroscopie techniques such as
EXAFS, XPS and laser induced fluorescence have been used. Two different
types of sorption sites on the thorium phosphate but only one on the
zirconium phosphate have been detected.