Sorption of Zinc (II) and Copper (II) Ions from Synthetic Wastewater by Yam (Dioscorea Rotundata) Peel Waste Biosorbent

Abstract

There is a growing concern about the potential health hazard posed by heavy metals in the environment. The removal of metals from individual wastewater has become of primary importance because contamination of wastewater by heavy metals is a very serious environmental and health problem. Some of the existing methods of wastewater treatment are beyond the abilities of many local industries. Of recent, the use of non-living biomaterials as metal-binding compounds has been gaining advantage because the high levels of contamination do not affect them. Moreover, they require minimum care and maintenance and can be obtained cheaply. In this study acid-activated yam peel waste biosorbent was used for the removal of Zn (II) and Cu (II) ions from synthetic wastewater under batch test conditions. The effects of initial concentration (15-55mg/l) and contact time (20-100min) on removal performance were investigated with maximum removal efficiencies of 38% and 89% obtained for Cu (II) and Zn (II) respectively within 100 min. The Langmuir isotherm model provided a better fit for the equilibrium data obtained. Furthermore, adsorption of both metals was best described by the pseudo second order kinetic model based on the higher correlation coefficients and smaller error values obtained from statistical analysis. The findings of this study indicate the potential of this biosorbent for heavy metal removal applications.