Use of response surface methodology for optimizing process parameters of thorium adsorption on amino-functionalized titanosilicate nanoparticles

The ability of amino-functionalized hydrothermally synthesized titanosilicate nanoparticles (TiSiNH2) was investigated for the adsorption of Th(IV) from aqueous solutions in batch mode. The effects of four process independent variables including pH, initial metal concentration, sorbent amount and temperature were investigated using response surface methodology (RSM) based on central composite design (CCD). The accuracy of model was verified by coefficient of determination. The results of optimization showed that the sorption capacity of TiSiNH2 for Th(IV) under optimal conditions was 83.04 mg g-1. The results of modeling showed that, experimental data of adsorption capacity of sorbent for Th(IV) were better fitted with double exponential kinetic model and Langmuir isotherm can describe the equilibrium data well. The maximum adsorption capacity of TiSiNH2 for Th(IV) was estimated to be 87.71 mg g-1 by Langmuir isotherm.