abstract
This paper presents a mathematical model for the transport of Ce(IV) from sulfate solutions through dispersion supported liquid membranes which contain 2-ethyl hexyl phosphoric acid-mono-2-ethyl hexyl ester (P204) as the carrier, dissolved in kerosene as the membrane solution. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick’s second law. The equations for transport velocity are derived considering the diffusion of P204 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce(IV) and the carrier takes place only at the solvent–aqueous interfaces. Modeling of concentration profiles is obtained for the Ce(IV) from which extraction velocities are predicted. The experimental and simulated Ce(IV) extractions showed similar tendencies for a high Ce(IV) concentration and acidity case. The model results indicate that the initial high concentration of Ce(IV) and acidity have detrimental effects on Ce(IV) extraction and stripping.
Acknowledgments
This work is financially supported by the National Natural Science Foundation of China for Young Scientists (51109197), the Foundation for Planning project of West Action of Chinese Academy of Sciences (KZCX2-XB2-13) and Research Fund for Excellent Doctoral Thesis of Xi’an University of Technology (602-210805).