Abstract—In recent years, there has been increasing interest in the use of biomass from microbial sources, particularly the microalgae, to absorb multimetal ions in the waste water. The other type of treatment like ion exchange, evaporation, precipitation, membrane separation etc. are too expensive to treat low levels of heavy metal in wastewater. This work demonstrated the biosorption of a mixture of heavy metals solution with silica gel immobilized micro algae Comparison of metal uptake in single and multi-component aqueous solutions of Cu-Zn was discussed. The results suggested that there should exist a competitive adsorption for the binary mixture solution as the adsorption capacity for the primary heavy metal often dropped with the introduction of the secondary heavy metal. The adsorption capacity was also found to decrease for the cases of binary adsorption. The biosorption equilibrium data obeyed Langmuir and Freundlich model in the concentration ranges studied. The preference of investigated biosorbent for metals is as follows Cu>Zn. The sorption processes were found to be slower in multi-component than those in the single-component metal solutions. Concerning copper, and zinc, no significant removal efficiency could be noticed between single and multi-component aqueous metal solutions in the presence of NO3 and SO4 anions. On the contrary, presence of chloride ions significantly decreased efficiency of metal biosorption. The presence of Ca and Mg ion did not affect the adsorption of Cu ion whereas these ions considerably affect the adsorption of Zn ion. This finding is highly important for the design of the adsorption system and it can be used for metal uptake in waste water treatment.
Department of chemical engineering, annamalai university, annamalai nagar. India.
Cite: R. Ramsenthil and Rm. Meyyappan, "Single and Multi-component Biosorption of Copper and Zinc Ions using Microalgal Resin," International Journal of Environmental Science and Development vol. 1, no. 4, pp. 298-301, 2010.