Comparative study of synthesized Kaolinite supported-metal oxides for Th (IV) adsorption

Abstract

Egyptian natural kaolinite was supported with metal oxides ZnO and CuO to prepare modified kaolinite KCu and KZn for Th(IV) adsorption from an aqueous solution. Different analyses such as SEM, EDX, XRD, and FTIR described the morphology and structural characteristics of the new adsorbents KCu and KZn. The adsorption process was applied in batch experiments as a function of pH, contact time, initial Th(IV) concentration, temperature, regeneration, and reusability. The equilibrium stage was achieved at 120 min. Experimental data were well described by the pseudo-second-order and Langmuir models with maximum adsorption capacities of 62.89 and 56.179 mg/g for KCu and KZn, respectively. Thermodynamic parameters were calculated and proved the spontaneous and endothermic nature of the adsorption process, which showed that the modified kaolinite is sensitive to temperature. Thermodynamics studies confirmed that adsorption is feasible and spontaneous. The regeneration and reusability study showed that KCu and KZn are economically viable.