Sorption of cesium and gadolinium ions onto zirconium silico antimonate sorbent from aqueous solutions.

ABSTRACT

Using a batch equilibrium technique, the sorption of 137Cs and 153Gd onto synthesized zirconium silico antimonate (ZrSiSb) sorbent was examined. The new sorbent was prepared by precipitation technique and characterized by diverse analytical tools. The influence of shaking time, pH, metal ion concentrations, temperature, and a real sample was carried out. The data indicate that ZrSiSb has a very fast equilibrium time (30 min). The distribution coefficient values as a function of pH have sequence order; Cs(I) > Gd(III). The reaction kinetic obeys the pseudo-2nd-order model. The saturation capacity is 69.8 and 27.2 mg/g for Cs(I) and Gd(III), respectively. Equilibrium data were analyzed by various sorption isotherm models. Desorption studies showed that the best eluents for complete recovery (about 99%) of the selected ions are KCl for Cs(I) and CaCl2 for Gd(III). The sorption effectiveness of the new ZrSiSb to remove 137Cs and 153Gd from real low-level radioactive waste was examined. The results obtained showed that the prepared new composite can be applied as a hoped sorbent material to get rid of these radionuclides from different wastewaters.