Batch Adsorption Kinetics of Zinc Ions Using Activated Carbon from Waste Nigerian Bamboo

Ademiluyi F.T, Alex Abidde

Batch adsorption kinetics of Zinc ions using activated carbon from waste Nigerian bamboo was investigated. The bamboo was cut into sizes,  washed,  dried and carbonized at 300oC-500oC. It was then activated at 800oC using nitric acid.  The effect of contact time on the adsorption of zinc ions in aqueous solution was also investigated and were found to significantly affect the adsorption capacity of zinc ions . The adsorption process fitted well into the Freundlich, and Langmuir isotherm models indicating a monolayer formation over the surface of the material. Langmuir isotherm had monolayer saturation capacity of 250 mg/g  of zinc ions adsorbed per g of bamboo activated carbon and high adsorption intensity of 1.579. In order to determine the mechanism of sorption, kinetic data were modeled using the pseudo first order , pseudo second order kinetic equations, and intra-particle diffusion model. The pseudo second order equation was the best applicable model to describe the sorption process. Hence the pseudo second order kinetic reaction is the rate controlling step with some intra particle diffusion taking place during the adsorption.