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Journal of Thermal Analysis and Calorimetry

, Volume 101, Issue 2, pp 519–526 | Cite as

Studies on the equilibrated thermodesorption of n-hexane from ZSM-5 zeolite

The influence of the extraframework cations
  • Dorota MajdaEmail author
  • Wacław Makowski
Article

Abstract

Equilibrated thermodesorption (TPED) and quasi-equilibrated temperature programmed desorption and adsorption (QE-TPDA) were employed as methods for studying the influence of different extraframework cations (Na+, K+, Li+, Cu2+, Zn2+, or Mg2+) on adsorption of n-hexane on ZSM-5 zeolite with high Al content (Si/Al = 15). Considerable influence of the cations on both initial adsorption in the micropores and ordering of the adsorbed molecules, occurring at high coverages, has been observed. This influence is reflected by the values of the adsorption enthalpy and entropy, determined by fitting the dual site Langmuir (DSL) adsorption function to the equilibrated thermodesorption profiles. However, no clear correlation between the determined parameters and properties of the extraframework cations could be found.

Keywords

ZSM-5 n-Hexane Desorption Adsorption Extraframework cations 

Notes

Acknowledgements

The authors thank the Polish Ministry of Science and Higher Education for financial support (grant number N507 108 32/3175).

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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2010

Authors and Affiliations

  1. 1.Department of ChemistryThe Jagiellonian UniversityKrakówPoland

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