Biosorption of heavy metals by potassium hydrogen phosphate and sodium oxalate modified lignocellulosic waste

Abstract

Heavy metals are among the most toxic nuisances that pose a huge pressure on the environment. This in effect calls for for the development of a noble low cost and efficient technology for the removal of heavy metal from industrial effluents. In this particular research, lead (II) biosorption capacity of chemically modified lignocellulosic wastes (rice husk and sugarcane bagasse) has been studied. The two selected biosorbents are abundant and low cost biosorbents with promising potential to remove hazardous heavy metals from effluent streams. In the study, after executing rigorous investigation on the potential of several chemical modifiers, potassium hydrogen phosphate and sodium oxalate were found to be the best modifiers to improve the sorption capacity of rice husk and sugarcane bagasse. Besides, impact of particle size and pH has been studied. Characterization of the sorbent surfaces has been made before and after chemical modification and after sorption of heavy metals using furrier transform infra-red spectroscopy (FTIR). For the selected chemically modified sorbents of rice husk and sugarcane bagasse intensive study was performed on the sorption kinetics for varying metal and sorbent doses.