Eggshell powder as an adsorbent for removal of Cu (II)‎ and Cd (II)‎ from aqueous solution : equilibrium, kinetic and thermodynamic studies

Abstract EN

The adsorption of Cu (II) and Cd (II) ions onto eggshell was investigated.

The effects of contact time, initial pH of solution, adsorbent dosage, initial metal concentration, agitation speed, and temperature were studied in batch experiments.

The maximum adsorption capacities for Cu(II) and Cd(II) were 8.4 and 7.01 mg/g, respectively.

Thermodynamic parameters such as Gibbs free energy change, Enthalpy change and Entropy change have been calculated.

These thermodynamic parameters indicated that the adsorption process was thermodynamically spontaneous under natural conditions and the adsorption was endothermic in nature.

Experimental data were also tested in terms of adsorption kinetics, the results illustrated that the adsorption process was following pseudo second- order kinetics.

In addition Fourier transfer infrared spectroscopy (FTIR) analysis suggests that Cu (II) and Cd (II) interact with metal oxides and -OH functional group present in eggshell powder.