Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-28T12:14:10.251Z Has data issue: false hasContentIssue false
  • English
  • Français

Mesoscopic modeling of binary diffusion through microporous zeolite membranes

Published online by Cambridge University Press:  11 February 2011

Mark A. Snyder  and
Dionisios G. Vlachos
Mark A. Snyder
Affiliation:
Department of Chemical Engineering and Center for Catalytic Science and Technology (CCST), University of Delaware, Newark, DE 19716–3110, U.S.A.
Dionisios G. Vlachos
Affiliation:
Department of Chemical Engineering and Center for Catalytic Science and Technology (CCST), University of Delaware, Newark, DE 19716–3110, U.S.A.
Get access

Abstract

The mesoscopic framework describing single-component diffusion through microporous materials is extended here to characterize binary diffusion in the absence of intermolecular forces. Two diffusion mechanisms, single-file diffusion characteristic of confined pore structures and species-species exchange consistent with diffusion modes in less-confined pore topologies, are incorporated at the Master Equation level. Derived fundamentally via rigorous coarse-graining of the underlying Master Equation, the binary mesoscopic relation is validated via direct comparison to gradient continuous time Monte Carlo (G-CTMC) simulations. We further show the capability of this fundamentally derived model to capture the macroscopic diffusion phenomenon of ‘overshoot’ or ‘roll-up’ in the transient uptake and flux. Exploration of the species-species exchange mechanism reveals its strong effect on the transient ‘overshoot’ behavior through relaxation of the constrained single-file diffusion.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 752: Symposium AA – Membranes–Preparation, Properties and Applications , 2002 , AA7.8
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Krishna, R., Chemical Engineering Science. 45, 1779 (1990).Google Scholar
2. Kapteijn, F., et al., CEJ. 57, 145 (1995).Google Scholar
3. van den Broeke, L.J.P., Nijhuis, S.A., and Krishna, R., Journal of Catalysis. 136, 463 (1992).Google Scholar
4. Krishna, R. and van den Broeke, L.J.P., CEJ. 57, 155 (1995).Google Scholar
5. van de Graaf, J.M., Kapteijn, F., and Moulijn, J.A., AIChE Journal. 45, 497 (1999).Google Scholar
6. van den Broeke, L.J.P., AIChE Journal. 41, 2399 (1995).Google Scholar
7. Qureshi, W.R. and Wei, J., Journal of Catalysis. 126, 126 (1990).Google Scholar
8. Snyder, M.A., Vlachos, D.G., and Katsoulakis, M.A., Chemical Engineering Science. In press, (2002).Google Scholar
9. Lam, R., et al., Journal of Chemical Physics. 115, 11278 (2001).Google Scholar
10. Vlachos, D.G. and Katsoulakis, M.A., Physical Review Letters. 85, 3898 (2000).Google Scholar
11. Lam, R., Vlachos, D.G., and Katsoulakis, M.A., AIChE Journal. 48, 1083 (2001).Google Scholar
12. Qureshi, W.R. and Wei, J., Journal of Catalysis. 126, 147 (1990).Google Scholar
13. Krishna, R. and Wesselingh, J.A., Chemical Engineering Science. 52, 861 (1997).Google Scholar
14. Aghalayam, P., Park, Y.K., and Vlachos, D.G., AIChE J. 46, 2017 (2000).Google Scholar