The kinetics of copper sorption onto yohimbe bark wastes

Kinetics of Cu (II) sorption onto yohimbe bark wastes have been investigated at various initial metal concentration, sorbent mass, agitation speed and particle size. The kinetic data have been treated by using two kinetic models the pseudo-first order equation and the pseudo-second order equation. Results showed that chemical sorption is the rate-control ling step and that the mechanism of mass transport by diffusion across the liquid film surrounding the yohimbe particles is not a limiting step in the sorption process. ton exchange was found to be the main responsible mechanism for copper ions uptake.