REMOVAL OF Pb2+ IONS FROM AQUEOUS SOLUTIONS BY SLOVAK BENTONITES

The adsorptive properties of Slovak bentonites from deposits Jelsovy Potok and Lieskovec for the removal of Pb2+ ions from aqueous solutions were studied in a batch adsorption system at room temperature. The effect of pH, initial concentration of Pb2+ ions, contact time and amount of bentonite were investigated. It was found that the amount of adsorption of metal ion increased with the initial solution pH, metal ion concentration and contact time, but was decreased with the amount of adsorbent. The equilibrium adsorption capacity of the adsorbents used for Pb2+ ions was extrapolated using the linear Freundlich and Langmuir adsorption isotherms. The experimental data measured for both bentonites were fitted better to the Langmuir isotherm from which the maximum adsorption capacity was calculated. By comparing the measured results for both bentonites it is evident that the bentonite from Jelsovy Potok is more suitable for sorption of lead.