Adsorption of Cd(II) And Fe(II) from Aqueous Solution Using Adsorbents Prepared from Waste Polythene Sachets

The adsorption of Fe(II) and Cd(II) ions from aqueous solution was studied using adsorbents prepared from waste polythene sachets. The effect of initial ion concentration, contact time, pH, adsorbent dose and temperature on the removal of Fe(II) and Cd(II) ions was examined. The optimum concentration was found to be 40 ppm for Fe(II) and 50 ppm for Cd(II) ions. The equilibrium data fit the Langmuir isotherm better than the Freundlich and Temkin isotherms. The negative values of the Gibbs free energy (ΔG) revealed that the adsorption process is feasible and spontaneous. The adsorption of Cd(II) ion was found to be spontaneous at 323 K on sulfuric acid activated samples but not spontaneous at all on carbonized samples. The adsorption data fit well into the pseudo-second-order kinetic model and the experimental quantities of Cd(II) and Fe(II) adsorbed are relatively close to the calculated quantities adsorbed. The prepared adsorbents therefore offer an alternative for the removal of the metal ions from contaminated water.