Usage of Iranian scoria for copper and cadmium removal from aqueous solutions

The competitive removal of copper and cadmium from aqueous solutions using scoria has been investigated. Scoria was characterized by various methods, such as XRD, XRF, FT-IR and SEM. The results show that scoria sample contained augite, enstatite, diopside, and olivine. These minerals were separated from each other and each mineral was then subjected to the adsorption experiments. It was found that the main absorbent constituent in scoria was augite. Finally, statistical experimental method was used to optimization of adsorption conditions(Initial concentration of copper and cadmium ions, the amount of scoria and temperature) for removal of Cu(II) and Cd(II) ions from solution in optimum conditions. The optimum conditions are obtained as follows: concentrations of Cu(II) and Cd(II) of 400×10-6 and 554×10-6, respectively; amount of scoria of 7 g; temperature of 38 °C. Under these conditions Cu(II) and Cd(II) ions are absorbed onto the scoria more than 79% and 16%, respectively.