Estimation of Binding Constants of Cd(II), Ni(II) and Zn(II) with Polyethyleneimine (PEI) by Polymer Enhanced Ultrafiltration (PEUF) Technique

Continuous and batch processes of polymer enhanced ultrafiltration for the estimation of binding constants of divalent cadmium, nickel, and zinc ions have been elaborated. Polyethyleneimine was used as a complexation agent. Effect of pH and ionic strength on the binding ability of target metal ions to polyethyleneimine were estimated by continuous mode PEUF system. A mathematical model was developed to estimate apparent complexation constants of metal ions with PEI. The development of this model, which is in good agreement with experimental data, enables to compare the data obtained in both continuous and batch system and correlate the effect of pH and ionic strength with apparent binding constants

Removal of Heavy Metals from Multicomponent Metal Mixtures by Polymer Enhanced Ultrafiltration: Effects of pH, Ionic Strength and Conformational Changes in Polymer Structure

Fractional separation of industrially important heavy metals (cadmium, nickel, zinc) from binary and ternary metal mixtures by continuous mode polymer enhanced ultrafiltration was studied. Polyethyleneimine (PEI) was used as a complexation polymer. Effects of pH and ionic strength on process efficiency were investigated. To gain insight about the characteristics of binding between highly branched PEI and metal ions and effect of salt concentration on this binding were investigated by performing dynamic and static light scattering measurements. It was observed that with optimum pH and salt concentration, fractional separation of metals can be achieved