USE OF COCONUT BAGASSE AS ALTERNATIVE ADSORBENT FOR SEPARATION OF COPPER (II) IONS FROM AQUEOUS SOLUTIONS: ISOTHERMS, KINETICS, AND THERMODYNAMIC STUDIES

作者：Sousa Neto Vicente O; Oliveira Andre G; Teixeira Raimundo N P; Silva Marcos A A; Freire Paulo T C; Keukeleire Denis D; Nascimento Ronaldo F^*

来源：BioResources, 2011, 6(3): 3376-3395.

DOI：10.15376/biores.6.3.3376-3395

• Coconut bagasse
• Copper(II)
• Adsorption kinetics
• Thermodynamics

The use of coconut bagasse as an adsorbent for the treatment of Cu(II) ions from aqueous solutions has been investigated. The adsorbent was characterized by infrared spectroscopy, including zeta potential and pH effects. To assess the possibility of removing Cu(II) from aqueous solutions by this sorbent the effects of contact time, initial metal ion concentration, and temperature were studied at pH 5.5. Kinetic studies showed that the amount adsorbed increased with initial Cu(II) concentration, and the equilibrium was established in 120 min. The kinetic data were analyzed using a pseudo second-order equation. Adsorption equilibrium data were investigated using the Langmiur, Freundlich, D-R, Temkin and Halsey isotherm models. The adsorption of Cu(II) on the coconut bagasse was endothermic (Delta H degrees 86.2 kJ/mol), resulting in an increase in entropy (Delta S degrees 339 J/mol/K) and a decrease in Gibbs free energy (Delta G -16.34 to -22.44 kJ/mol) in the temperature range of 301-313 K. A reduction in adsorption capacity with an increase in heat of adsorption revealed an ion exchange mechanism for Cu(II) adsorption.

• 出版日期2011