skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Correlation and prediction of liquid-phase adsorption on zeolites using group contributions based on adsorbate-solid solution theory

Abstract

Both correlation as well as prediction of experimental data for the adsorption of various binary liquid mixtures of alkanes and alkenes on NaX at different temperatures are presented. The theoretical background is based on the adsorbate-solid solution theory which conceives the adsorbed phase to be a mixture of the adsorbed species (adsorbate) and the adsorbent as an additional component. With the introduction of the Gibbs excess energy G{sup E*} for this hypothetical mixture, activity coefficients and composition of the adsorbed phase may be calculated. The Biggs excess energy and thus the activity coefficient of the adsorbed species depend strongly on the energetic heterogeneity of the solid surface which may be described by use of so-called group contribution models. These approaches, until now widely applied to predict fluid-phase equilibrium, are derived from statistical thermodynamics and take into account the energetic interactions between the respective components. For the application of this approach on thermodynamics of adsorption zeolites have to be divided into different functional groups such as SiO{sub 2}, AlO{sub 2}{sup {minus}}, and the respective cations. The interaction energies between these active sites and the functional groups of the adsorbed liquid molecules represent fundamental parameters of activity coefficient models based on groupmore » contributions such as UNIFAC. These parameters were determined by fitting four different adsorption systems. With the fitted values, six other systems were predicted. Both correlation and prediction include adsorption data at different temperatures. All calculations show excellent results with a mean relative deviation of 4.2% for the correlation and a mean deviation in the range of 8--17% for the predictions.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Univ. Dortmund (DE)
OSTI Identifier:
20000532
Report Number(s):
CONF-9808111-
Journal ID: ISSN 0743-7463; LANGD5
Resource Type:
Journal Article
Journal Name:
Langmuir
Additional Journal Information:
Journal Volume: 15; Journal Issue: 18; Conference: Third international symposium on effects of surface heterogeneity in adsorption and catalysis on solids, Torun (PL), 08/09/1998--08/16/1998; Other Information: PBD: 31 Aug 1999; Journal ID: ISSN 0743-7463
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; ZEOLITES; SORPTIVE PROPERTIES; ALKANES; ALKENES; ADSORPTION; BINARY MIXTURES; MATHEMATICAL MODELS; THERMODYNAMIC PROPERTIES

Citation Formats

Berti, C., Ulbig, P., Burdorf, A., Seippel, J., and Schulz, S. Correlation and prediction of liquid-phase adsorption on zeolites using group contributions based on adsorbate-solid solution theory. United States: N. p., 1999. Web. doi:10.1021/la981415p.
Berti, C., Ulbig, P., Burdorf, A., Seippel, J., & Schulz, S. Correlation and prediction of liquid-phase adsorption on zeolites using group contributions based on adsorbate-solid solution theory. United States. doi:10.1021/la981415p.
Berti, C., Ulbig, P., Burdorf, A., Seippel, J., and Schulz, S. Tue . "Correlation and prediction of liquid-phase adsorption on zeolites using group contributions based on adsorbate-solid solution theory". United States. doi:10.1021/la981415p.
@article{osti_20000532,
title = {Correlation and prediction of liquid-phase adsorption on zeolites using group contributions based on adsorbate-solid solution theory},
author = {Berti, C. and Ulbig, P. and Burdorf, A. and Seippel, J. and Schulz, S.},
abstractNote = {Both correlation as well as prediction of experimental data for the adsorption of various binary liquid mixtures of alkanes and alkenes on NaX at different temperatures are presented. The theoretical background is based on the adsorbate-solid solution theory which conceives the adsorbed phase to be a mixture of the adsorbed species (adsorbate) and the adsorbent as an additional component. With the introduction of the Gibbs excess energy G{sup E*} for this hypothetical mixture, activity coefficients and composition of the adsorbed phase may be calculated. The Biggs excess energy and thus the activity coefficient of the adsorbed species depend strongly on the energetic heterogeneity of the solid surface which may be described by use of so-called group contribution models. These approaches, until now widely applied to predict fluid-phase equilibrium, are derived from statistical thermodynamics and take into account the energetic interactions between the respective components. For the application of this approach on thermodynamics of adsorption zeolites have to be divided into different functional groups such as SiO{sub 2}, AlO{sub 2}{sup {minus}}, and the respective cations. The interaction energies between these active sites and the functional groups of the adsorbed liquid molecules represent fundamental parameters of activity coefficient models based on group contributions such as UNIFAC. These parameters were determined by fitting four different adsorption systems. With the fitted values, six other systems were predicted. Both correlation and prediction include adsorption data at different temperatures. All calculations show excellent results with a mean relative deviation of 4.2% for the correlation and a mean deviation in the range of 8--17% for the predictions.},
doi = {10.1021/la981415p},
journal = {Langmuir},
issn = {0743-7463},
number = 18,
volume = 15,
place = {United States},
year = {1999},
month = {8}
}