Modification of Amberlite XAD-2 resin for U(VI) adsorption from Egyptian crude phosphoric acid

Adsorption of U(VI) from Egyptian crude phosphoric acid was studied using the modified Amberlite XAD-2 resin. Modification process was performed by soaking Amberlite XAD-2 resin in tri-butyl phosphate (TBP) and di-2-ethyl hexyl phosphoric acid (D2EHPA) for increasing its adsorption capacity via equilibrium batch technique. For this purpose, different effective parameters such as: a dose of adsorbent, contact time, temperature, phosphoric acid concentration, and initial uranium (VI) concentration were investigated. The maximum sorption capacity by the modified resin achieved 67 mg g−1 of U (VI). Sorption of U (VI) follows both the Langmuir and Freundlich adsorption isotherms. Not less than 93% of the U (VI) uptaken by the modified Amberlite XAD-2 resin was desorbed using 1 mol L−1 NaCl + 0.1 mol L−1 H2SO4. Keywords: Uranium (VI), Amberlite XAD-2, Tri-butyl phosphate (TBP), Di-2-ethyl hexyl phosphoric acid (D2EHPA), Phosphoric aci