Ehsan Zamani Souderjani - Department of Chemical Engineering, Collage of Engineering, University of Tehran, Tehran, Iran
Ali Reza Keshtkar - Nuclear Fuel Cycle School, Nuclear Science and Technology Research Institute, Tehran, Iran
Mohammad Ali Mousavian - Department of Chemical Engineering, Collage of Engineering, University of Tehran, Tehran, Iran

In this work, thorium(IV) removal from aqueous solutions was investigated in batch systems of cationic and anionic resins of Amberlite IR-120 and IRA-400. In this way, the effects of pH, initial Th(IV) concentration and the amount of adsorbent were investigated. A Central composite design (CCD) under response surface methodology (RSM) was employed to determine the optimized condition. The results showed that the maximum removal efficiency of Th(IV) onto IR-120 and IRA-400 either discretely or in combination, albeit with equal mass fraction, was determined as follows: 98.09% , 65.70% and 72.19% at pH=3.23, 6 and 4.07, initial Th(IV) concentration of 78.2,30 and 55.4 mg.L-1 and 2.08, 2.5 and 2.2 g.L-1 of resin, respectively. The kinetic and equilibrium data were accurately described by the pseudo-second order and Langmuir models. The results showed that IR-120 is a suitable adsorbent for thorium removal from aqueous solutions

Th(IV) removal,Response surface methodology (RSM),Central composite design,Ion exchange resin,,