Equilibrium Isotherm, Thermodynamic and K inetic Studies of Lead adsorption onto pineapple and paper waste sludges

The adsorptions of lead from aqueous solution by pineapple and paper waste sludges are studied through equilibrium isotherm. Langmuir and Freundlich adsorption models are applied in order to describe the Langmuir coefficient (aL), Langmuir constant (KL), separation factor (SF), Freundlich constant (KF), intensity of Fruendlich adsorption (nF -1 ). The Gibb free energy (�G°), enthalpy (�H°), and entropy (�S°) are calculated for thermodynamic parameters. The adsorption of rate constant (kad) are determined with from kinetics studies; zeroorder, firstorder, and secondorder adsorption. The activation energy (Ea) of adsorption is applied with Arrhenius equation. Langmuir adsorption model presents better fit with experimental data. The kad from first and secondorder adsorption have the high correlation coefficient (R 2 ) with concentration 100250 ppm, temperature 3050 °C, and pH 6. Keywords—Equilibrium isotherm, Thermodynamic, Kinetic, Lead adsorption.