Metal Sorption Capabilities of Two Common Plants in Tropical Wetlands - Bambusa vulgaris and Raffia bambusa

Abstract

In most developing countries, careless disposal of waste dry cell batteries and Ni-Cd batteries from mobile phones and rechargeable lamps has led to an increase in some metal contaminants including copper, lead, nickel and cadmium in soils and water bodies. These metals have the potential to cause serious, and sometimes, irreversible health effects if they are consumed. Unfortunately, in most cases, either the water bodies are not treated prior to consumption or the water treatment methods do not target the removal of these metals. This study therefore sought to mimic the bio-filtering effect of wetlands by assessing the capabilities of two common plants in tropical wetlands; Raffia bambusa and Bambusa vulgaris to remove Cu²⁺, Pb²⁺, Ni²⁺ and Cd²⁺ from wastewater. Spectroscopic characterisation indicated that some of the functional groups on the biomass were the OH, C=O and COOH, and R. bambusa appeared to have more pronounced groups than B. vulgaris. The results show maximum sorption of 95% Cu and Pb by biomass derived from roots of these plants. Sorption of Cd and Ni were lower at about 40%. By using a 3-stage sorption system of live plants, sorption of Cd and Ni increased up to 80%.

Keywords: Heavy Metals, Sorption, Biomass, Bambusa vulgaris, Raffia bambusa