Removal of Sr (II) from aqueous solutions by adsorption using amberlite XAD-7 resin impregnated with TOPO extractant

This research investigation deals with efficiently removing strontium ions from aqueous solutions, a problem with significant environmental and health implications due to radioactive contamination. The performance and potential of Amberlite XAD-7 resin impregnated with TOPO extractant was evaluated to remove strontium ions from aqueous solutions. The influence of main operating conditions such as the initial pH, initial concentration of strontium in the solution, contact time, impregnation ratio, and adsorbent dosage, was evaluated. The adsorbents were characterized using SEM and FTIR analyses both before and after impregnation, as well as after the adsorption process. The study of the effect of contact time on the adsorption process was carried out in order to achieve the adsorption equilibrium time and determine the appropriate kinetic model. The experimental results showed that the adsorption process reaches equilibrium within 240 min, and the pseudo-second-order kinetic model is very suitable to describe this adsorption process (R2 > 0.99). Adsorption equilibrium modeling showed that the Langmuir isotherm model can well describe the equilibrium behavior of strontium adsorption by Amberlite XAD-7 resin impregnated with TOPO extractant (R2 > 0.99). The maximum uptake predicted by the Langmuir model for strontium adsorption using the TOPO impregnated Amberlite XAD-7 was 65.79 mg/g.