Characterization and Application of Olive Stones Activated Carbon for Uranium (VI) Sorption from Wet-process phosphoric acid: Kinetic, equilibrium and thermodynamic studies
Walid M. Youssef
In this work, uranium adsorption from Egyptian phosphoric acid onto chemical modified Olive Stones has been studied by two methods (H3PO4 and ZnCl2) at 800ºC was used to carbonized. The relevant factors affecting uranium adsorption onto our Olive Stones Activated Carbon adsorbent were studied. These factors involved phosphoric acid concentration, the contact time, adsorbent weight, initial uranium concentration and the temperature were investigated. The theoretical capacity of Olive Stones Activated Carbon adsorbent is about (47.8, 46.08) mg/g for O.S-H3PO4, O.S-ZnCl2 respectively. The optimum adsorption conditions were choiced in two methods and P2O5 ineffective by these conditions. The sorption process of uranium U(VI) follow Langmuir isotherm model with pseudo-second order mechanism and exothermic nature and spontaneous process according to studying (enthalpy change, entropy change and Gibbs free energy change). More Than 80 % of the loaded uranium amount on the Olive Stones Activated Carbon adsorbent has been eluted using 0.1 M HNO3 as an efficient eluent.