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

Abstract

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.

Thermodynamics and Mechanism of the Adsorption of Heavy Metal Ions on Keratin Biomasses for Wastewater Detoxification

“…Thermodynamic parameters for the adsorption of Pb 2+ ions with both keratin-based biomaterials were calculated using the van't Hoff equation [36]. In particular, the changes of entropy (ΔS 0 ), enthalpy (ΔH 0 ), and free energy (ΔG 0 ) of the adsorption of Pb 2+ ion on HH and SF were calculated using the next equations [36][37][38][39]:…”

“…where T is the adsorption temperature (K), R is the universal gas constant (8.314 J/mol K), and K d is the adsorption equilibrium constant calculated from the experimental Pb 2+ ion adsorption studies. ΔS 0 and ΔH 0 were obtained from the linear regression of ln K d versus 1/T [36,38] where K d was obtained from the distribution coefficient according to the procedure reported in [39] using the experimental Pb 2+ ion adsorption data.…”