Collect. Czech. Chem. Commun. 1985, 50, 2788-2803

The influence of dispersion forces on the mercury intrusion into pores of solids

Ondřej Kadlec

The J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, 121 38 Prague 2


On the basis of the Gibbs condition of thermodynamic equilibrium of heterogeneous system occuring in a force field, a general expression is derived for the dependence of the liquid mercury pressure on an equivalent radius of pores volume-filled on its intrusion. For the equivalent radius r of pores greater than 30 nm, this equation turns into the well-known Washburn equation. It is shown that for pores of equivalent radii smaller than 5 nm, the presence of dispersion forces is the reason of considerable deviations from the classical Washburn equation. The effect of the liquid mercury pressure on the contact angle θ of intruded mercury with pore walls is also discussed.