Adsorption Property of Cesium onto Modified Macroporous Silica–Calix[4]arene-crown Based Supramolecular Recognition Materials

The adsorption behavior of Cs(I), one of the heat generators, in HNO 3 medium was investigated at 298 K. The impact of U(VI), some typical elements, and temperature on the adsorption of Cs(I) was evaluated. It was performed by macroporous silica-based 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-calix[4]arene (Calix[4]arene-R14) impregnated supramolecular recognition materials (Calix[4] + M)/SiO 2 –P. They were modified with tri- n -butyl phosphate (TBP), octanol (Oct), and methyloctyl-2-dimethylbutanemide (MODB). The excellent adsorption ability and high selectivity of (Calix[4] + M)/SiO 2 –P for Cs(I) except Rb(I) and U(VI) were confirmed. The adsorption ability of Cs(I) onto the modified supramolecular recognition materials was (Calix[4] + Oct)/SiO 2 –P > (Calix[4] + TBP)/SiO 2 –P > (Calix[4] + MODB)/SiO 2 –P. The chromatographic separation of Cs(I) from a 4.0 M HNO 3 solution containing La(III), Sr(II), Ru(III), Cs(I), Rb(I), U(VI), Mo(VI), Zr(IV), Gd(III), and Pd(II) was carried out with a (Calix[4] + TBP)/SiO 2 –P packed column. Cs(I) was eluted effectively with water. The possibility and feasibility of effective partitioning of Cs(I) from highly active liquid waste by the (Calix[4] + M)/SiO 2 –P materials was evaluated.