EQUILIBRIUM SORPTION OF COPPER(II)-ETHYLENEDIAMINETETRAACETIC ACID CHELATES ONTO CROSS-LINKED, POLYAMINATED CHITOSAN BEADS

The sorption equilibria of copper(II) chelates of EDTA (ethylenediamin etetraacetic acid) from an equimolar solution with cross-linked, polya minated chitosan beads were investigated. The polyamination was done b y introducing different molecular weights of water-soluble poly(ethyle nimine) (PEI). Experiments were carried out as a function of the pH, c oncentration of Cu(II) ions, and temperature. It was shown that whethe r the initial aqueous phase was acidic or basic, it tended to become n eutral after sorption. The amount of sorption increased with increasin g the initial concentration of Cu(II) ions, temperature, and molecular weight of PEI introduced into the bead. Moreover, the measured equili brium isotherms could be correlated by a dual sorption model containin g the BET equation for a finite number of layers.