Abstract
Explicit Nernst-Planck approximation is applied to study the reaction kinetics for four heavy metal ions (Cd2+, Cu2+, Zn-2 and Pb2+) of environmental importance on the surface of cellulose acetate Zr(IV) molybdophosphate composite cation-exchanger. The composite cation-exchanger possessed ion exchange capacity of 1.96meqg(-1). The kinetic studies are carried out under particle diffusion controlled phenomenon. On the basis of kinetic studies various physical parameters i.e. fractional attainment of equilibrium U(tau), self diffusion coefficients (D-0), energy of activation (E-a) and entropy of activation (Delta S-*) are estimated to evaluate the mechanism of ion exchange on the surface of composite ion exchange material. The activation entropy and energy revealed that the greater degree and minimum energy was achieved during forward ion exchange process.