Authors: Okoche K. Amadi*, Gentle C. Onwuasoghianya, Innocent A. Okoro, and Nneamaka N. Ozuluonye
Received 27 November 2020/Accepted 29 December 2020
Metal detoxification of waste water and industrial effluents is significant in preserving aquatic life especially in the current era of increasing environmental contamination from industrial and domestic wastes. In this study, the batch sorption process was employed to investigate the effect of pH and time on the adsorption mechanism of Pb2+, Cd2+ and Ni2+ on the surface of Centrosema pubescens seed pod. The optimum time and pH for maximum adsorption of the three heavy metal ions were 120 min and 6.0 respectively. The adsorption process was best described by a pseudo second-order kinetic models which provided data that were in best agreement with experimental data compared to a pseudo first-order model. However, the mechanism occurred through both intra particle diffusion and liquid film diffusion. The transport mechanism for the process involved both intra-particle and liquid
