Adsorption Kinetics of Cd(ll) and Pb(ll) Ions from Aqueous Solutions by Bamboo-Based Activated Charcoal and Bamboo Dust

Abstract

The use of bamboo dust (BD) and bamboo-based activated charcoal for adsorption of Pb(ll) and Cd(ll) ions from aqueous solutions were assessed in this work. The effect of contact time on the uptake of these metal ions was studied in batch process. The adsorption data were correlated with pseudo first-order, pseudo second-order and diffusivity kinetic models. Results show that pseudo second-order kinetic model gave the best description for the adsorption process. Kinetic studies further showed that the adsorption transport mechanism was particle-diffusion controlled for the adsorption process. Results obtained generally showed that lead(ll) ions were better adsorbed onto both adsorbents as compared to cadmium(ll). Comparison of sorption capacity for the two adsorbents shows that bamboo-based activated charcoal exhibited better removal for the metal ions than the bamboo dust.

Keywords

• adsorption
• activated charcoal
• bamboo dust
• kinetic models
• metal ions