ISSN:
1572-8757
Keywords:
liquid phase adsorption
;
adsorption equilibrium
;
adsorption isotherm theory
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Physics
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Abstract A new approach to describe the adsorption behavior of liquid mixtures on solid surfaces by use of GE-models is presented. In contrast to the classical formulation of adsorption equilibrium the adsorbed phase is considered to be a mixture containing the adsorbed species (adsorbate) and the adsorbent as additional component. By introducing the Gibbs excess energy GE* for this adsorbate-solid-solution the free energy of adsorption is correlated with the respective activity coefficients of all involved components. This concept, in the following briefly called ASST (adsorbate-solid-solution theory), thus leads to a thermodynamically consistent description of both the adsorption equilibrium and caloric properties. For evaluation purposes the Wilson model was used to calculate the Gibbs excess free energy GE*. First results show the good ability of ASST to correlate surface excess isotherms of different types and to predict their temperature dependence. Moreover, the concept enables the surface excess isotherm for a binary liquid mixture to be predicted if the parameters describing the interactions between adsorbent and the respective fluids have been estimated from different surface excess isotherms.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1008903401235
