Adsorption of heavy metal ions by natural and synthesised zeolites for wastewater treatment
The removal of heavy metal ions, Pb(II) and Cu(II), by adsorption using natural zeolite (NZ), synthesised zeolite (MCM-22) (SZ), and powdered activated carbon (PAC), were examined and compared. The influences of contact time, solution pH and adsorbate concentration have been tested in kinetic runs. The equilibrium sorption capacities of copper and lead ions on NZ, SZ and PAC were found to be 24.1, 43.5, 19.2, 128.9, 190.7 and 76.8 mg/g, respectively, at 30°C and a pH 5.0. The results indicate that the MCM-22 exhibits the highest adsorption capacity and can be used for metal ion removal in wastewater treatment.
Keywords: naturl zeolite, kinetics, heavy metals, adsorption isotherm, ion adsorption, wastewater treatment, powdered activated carbon, PAC, synthesised zeolite, metal removal