Journal
JOURNAL OF HAZARDOUS MATERIALS
Volume 136, Issue 3, Pages 938-945Publisher
ELSEVIER
DOI: 10.1016/j.jhazmat.2006.01.032
Keywords
zinc; lead; ion exchange; diffusion models; clinoptilolite
Categories
Ask authors/readers for more resources
The kinetics of zinc and lead ions removal by modified zeolite-clinoptilolite has been investigated. The rate of the ion exchange process for lead ions is faster than for zinc ions, as well as the time needed to reach the equilibrium. The ion exchange capacity of zeolite of lead ions is doubly higher than that of zinc ions. Diffusion models according to the Vermeulen's approximation, the parabolic diffusion model and the homogeneous diffusion model have been tested with the experimental data of ion exchange for zinc and lead. For both systems examined, the best fit of the models proposed with the experimental data was shown by the Vermculen's approximation and the homogeneous diffusion model with t -> t(infinity). The diffusion coefficients are calculated from kinetic models of lead ions they are of the order of 10(-6) cm(2)/min, constant for all examined initial concentrations and not dependent on time. The diffusion coefficients in the system of zinc ions is of the order of 10(-8) cm(2)/min, also independent of initial concentrations, but decreasing with time from the beginning of ion exchange to the equilibrium. (c) 2006 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available