Abstrait

Cation-exchange kinetics for variousmetal ions and thermodynamics studies for the adsorption ofmancozeb pesticide on ployaniline Sn(IV) phosphate cation-exchanger

Asif Ali Khan*, Inamuddin

Ion-exchange kinetics on an electrically conducting organic-inorganic composite cation-exchanger have been studied for Mg2+-H+, Ca2+-H+, Sr2+-H+, Ba2+-H+, Ni2+-H+, Cu2+-H+,Mn2+-H+ and Zn2+-H+ exchanges at 25,33,50 and 65(0.5)0C temperatures using approximated Nernst-Plank equation under the particle diffusion controlled phenomenon. In this consequent some physical parameters, i.e., fractional attainment of equilibrium U(), selfdiffusion coefficients (D0), energy of activation (Ea), and entropy of activation (S*) have been determined. The adsorption thermodynamic for the adsorption of mancozeb, a fungicide of the class ethylenebisdiothiocarba mate have also been demonstrated on the surface of this composite cation- exchanger at 25,35,450C.As a result some thermodynamic parameters like Freundlich constants, thermodynamic equilibriumconstants(Kï), standard free energy changes (G°), and standard enthalpy change(H°) and standard entropy changes (S°) have been evaluated.