Kinetic and thermodynamic analysis of selective adsorption of Cs(I) by a novel surface whisker-supported ion-imprinted polymer

摘要

The surface ion-imprinting concept and chitosan incorporated sol-gel process were applied to the synthesis of a new whisker-supported polymer for selective separation of Cs(I) from aqueous solution. The prepared polymer was characterized with Fourier transform infra-red spectroscopy and X-ray diffraction, and then it was used in the sorption-desorption process. The effect of pH, the sorption rate and the mass of sorbent on the sorption capacity of imprinted polymer were studied. Results showed that sorption equilibrium time was achieved in about 2 h and the kinetic study showed to be well followed the pseudo-second-order kinetic equation in the adsorption process. At the same time, the adsorption isotherms studies indicated that Langmuir isotherm equation for the monolayer adsorption process was fitted well in the adsorption process and the maximum adsorption capacity was 32.9 mgg~(-1). Selectivity experiments showed that adsorbed amount of Cs(I) ion onto Cs(I) ion-imprinted polymer was higher than all other studied ions and the relative selectivity coefficient (K') were all greater than 9. The developed method with precision relative standard deviation 1.26% and detection limit (3σ) 0.180 μg L~(-1) respectively, using inductively coupled plasma atomic emission spectrometry was successfully applied to the determination of trace cesium in different water samples with satisfactory results.