X-ray photoelectron study of complexation between uranyl group and chitosan

Abstract

The interaction of U with chitosan in sorption of U(VI) from sulfate solutions was examined by X-ray photoelectron spectroscopy. It was found that uranyl complexes are formed on the chitosan surface. They contain in the equatorial plane the nitrogen atom of the amino group, as well as, probably, oxygen atoms from the chitosan ring and free hydroxy groups. Prolonged exposure of the chitosan-U(VI) complex in a vacuum chamber of the spectrometer results in cleavage of the bonds linking the uranyl groups with amino and hydroxy groups, which is responsible for formation of U(IV) compounds on the surface with surface depletion in OH groups.