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Adsorption

, Volume 3, Issue 3, pp 197–208 | Cite as

An analytical method of micropore filling of a supercritical gas

  • K. Kaneko
  • K. Murata
Article

Abstract

The supercritical gas adsorbed in the micropore having a strong molecular field was presumed to transform into the quasi-vapor to be filled in the micropore (quasi-vaporization adsorption mechanism). The Dubinin-Radushkevitch (DR) equation for micropore filling of vapor was extended to the quasi-vaporized supercritical gas using the quasi-saturated vapor pressureP0 q and the inherent micropore volumeW L . The reason why the concepts ofP0q andW L were introduced was explained with the molecule-pore interaction potential theory which is based on the Lennard-Jones interaction. The extended DR equation was named the supercritical DR equation. TheW L was evaluated by the Langmuir plot of the adsorption isotherm for a supercritical gas and both ofP0q andW L provided the single reduced adsorption isotherms of supercritical NO, N2, and CH4 on activated carbon fibers and high surface area carbons were analyzed by the supercritical DR plots. The wide applicability of the reduced adsorption isotherm to these adsorption data was explicity shown. The two phase model of the organized and confined fluids was proposed in order to improve the quasi-vaporization adsorption mechanism.

Keywords

micropore filling supercritical gas carbon micropore nitrogen monooxide methane molecular assembly 

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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • K. Kaneko
    • 1
  • K. Murata
    • 1
  1. 1.Department of Chemistry, Faculty of ScienceChiba UniversityChibaJapan

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