Kinetics and equilibrium studies on the sorption of uranium and thorium ions were carried out from nitric acid solutions by
tri-n-butyl phosphate (TBP) loaded supported sorbent, commercially known as Egy-Sorb, using batch technique. Analysis of the
rate data in accordance with three kinetic models revealed that the particle diffusion process was the rate determining mechanism
and the sorption process of the metal ions onto impregnated sorbent follows first order reversible kinetics. The values of
the first order rate constants, the rate constants of intraparticle transport, and the particle diffusion coefficients for
the uranium and thorium ions were determined from the graphical representation of the proposed models. Experimental isotherms
of both ions were successfully fit to Langmuir and Freundlich isotherm models over the entire concentration range studied.
The effect of temperature on the equilibrium distribution values has been utilized to evaluate the changes in standard thermodynamic