Study on factors affecting heavy metal sorption characteristics of two geomaterials

Abstract

This study investigates effect of liquid to solid ratio, initial concentration of heavy metals, pH and composite heavy metal solution and nature of sorbent on sorption capacity of two different geomaterials such as clayey soil and moorum. The batch sorption experiments were carried out with the selected geomaterials using different heavy metal solutions such as Copper, Manganese, Zinc, Lead and Chromium. Based on the experimental results, the following conclusions are drawn i) increasing liquid to solid ratio decreases the removal rate of heavy metal, however heavy metal sorbed on unit mass of the sorbent increased at equilibrium ii) increase in pH and the initial heavy metal concentration leads to an increase in the heavy metal uptake by the geomaterials iii) nature of the clay mineral present in the geomaterials plays significant role in controlling the sorption characteristics of the geomaterials compared to amount of clay content present in the geomaterials iv) observed order of selectivity of heavy metals is Cr >Pb >Cu >Mn ~Zn.