Extraction equilibrium and thermodynamics of cesium with a new derivative of calix[4]biscrown

A new supermolecular recognition agent named tetra - tert -butyl-calix[4]-bis[(4-methly-1,2-phenylene-crown-6] ( Tert ButylCalixC) was synthesized. Batchwise experiments of extraction of Na(I), K(I), Rb(I), Cs(I), Sr(II), Ba(II), Ru(III) and Fe(III) from aqueous solution with Tert ButylCalixC/ o -nitroanisole were carried out. Effects of HNO 3 concentration, contact time and temperature on the extraction behavior were examined. The equilibrium established within 30 min implied a fast extraction kinetics. The optimal operation temperature was 298 K. Stoichiometry of Tert ButylCalixC and Cs(I) by electrospray ionization mass spectrometry characterization revealed 1:1 molar ratio. It was observed that the extraction system of Tert ButylCalixC/ o -nitroanisole was effective for selective removal of Cs(I), showing remarkable separation performance.