limit. Further, these models ( and their modifications ) do Multilayer adsorption is calculated for a one-component vanot predict important details in the isotherm ( such as por using ideas based on the Ono -Kondo lattice model. It is steps ) seen in data measured to high resolution ( 6, 7 ) .
shown that this model predicts the common types of adsorption Another significant limitation of these models is that they behavior: the Henry, Langmuir, and Frumkin equations as parcontain saturation vapor pressure as a parameter and describe ticular cases; multilayer isotherms including steps due to twoadsorption isotherms only for temperatures below the critical dimensional condensation; changes in the isotherm that occur point. These equations cannot be used, even empirically, for when the temperature is varied from subcritical to supercritical supercritical fluids because they give results that qualitaconditions. In this paper, we investigate the adsorption isotherm tively are incorrect. Investigations of supercritical fluids as the concentration approaches saturation conditions. The analysis shows that at conditions near saturation the Gibbs ad-show (8-17) that the adsorption behavior is fundamentally sorption has a weak divergence which can be described by either different from the standard (IUPAC) classification ( 18). a logarithmic singularity or an exponential singularity with Isotherms for supercritical fluids have a maximum in the small exponent ( less than 0.05 ) . แญง 1997 Academic Press
Gibbs adsorption as a function of pressure.