Critical adsorption of sulfur hexafluoride on a finely divided graphite substrate.

Journal article
(Original article)

Publication Details

Author(s): Thommes M
Journal: Berichte der Bunsengesellschaft für physikalische Chemie
Publication year: 1994
Volume: 98
Journal issue: 3
Pages range: 477-81-81
ISSN: 0005-9021
eISSN: 0372-8323


The adsorption behavior of a near-crit. fluid (SF6) on a finely dispersed graphitic adsorbent (graphitized carbon black; Vulcan 3-G) was studied. The surface excess concn. Γ was measured by approaching the crit. point along near-crit. isochores using a volumetric technique. From the scaling theory of crit. adsorption by Fisher and de Gennes it is expected that Γ diverges at the crit. point. At temps. well above criticality of the fluid (T-Tc ≥ 3 K) the authors found the expected increase of T with decreasing T; however, closer to Tc the adsorption does not increase further but decreases sharply for T → Tc. This unexpected behavior was also found when the expt. was repeated under microgravity conditions on the space platform EURECA I. A similar max. in Γ(T) was also obsd. for SF6 adsorbed in a mesoporous controlled-pore glass (CPG-10) with 31 nm mean pore diam. [on SciFinder(R)]

FAU Authors / FAU Editors

Thommes, Matthias Prof. Dr.
Lehrstuhl für Thermische Verfahrenstechnik

Last updated on 2019-07-03 at 20:53