Biosorption of Pb(II) and Cu(II) from Aqueous Solution Using Chicken Feathers: Thermodynamics and Mass Balance Studies

Thermodynamic and mass balance studies of Pb(II) and Cu(II) biosorption from aqueous solution using chicken feathers (CF) were carried out. Thermodynamic parameters such as standard free energy (ΔG0), enthalpy (ΔH0) and entropy (ΔS0) changes were calculated from the data obtained to predict the nature of adsorption by chicken feathers (CF). From the results, entropy changes were positive indicating an increase in disorderliness in the adsorption of Pb(II) and Cu(II) onto the chicken feathers (CF). The negative values of Gibbs free energy and positive values of enthalpy indicated that the adsorption process by CF was spontaneous and endothermic. Data obtained also showed that the percentage Cu(II) and Pb(II) released by CF after digestion at 25 mg/l were higher than those released at 100 mg/l. Finally, FTIR analysis confirmed the presence of carboxyl, hydroxyl, amino and sulphur containing functional groups on CF, with no substantial variation in the spectra obtained before and after adsorption indicating a possible re use of CF.