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Published on: November 8, 2012
Variable diffusivity homogeneous surface diffusion model and analysis of merits and fallacies of simplified
V J Inglezakis1, M M Fyrillas2, J Park3
1Nazarbayev University, School of Engineering, Chemical & Materials Engineering Department, Environmental Science & Technology Group (ESTg), Astana, Kazakhstan; The Environment and Resource Efficiency Cluster (EREC), Nazarbayev University, Astana, Kazakhstan.
Abstract:
Adsorption and ion exchange phenomena are encountered in several separation processes, which in turn, are of vital importance across various industries. Although the literature on adsorption kinetics modeling is rich, the majority of the models employed are empirical, based on chemical reaction kinetics or oversimplified versions of diffusion models. In this paper, the fifteen most popular simplified adsorption kinetics equations are presented and discussed. A new versatile variable-diffusivity two-phase homogeneous diffusion model is presented and used to evaluate the analytical adsorption models. Aspects of ion exchange kinetics are also addressed.
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