Correlation effects during liquid infiltration into hydrophobic nanoporous media

Abstract

Correlation effects arising during liquid infiltration into hydrophobic porous medium are considered. On the basis of these effects a mechanism of energy absorption at filling porous medium by nonwetting liquid is suggested. In accordance with this mechanism, the absorption of mechanical energy is a result expenditure of energy for the formation of menisci in the pores on the shell of the infinite cluster and expenditure of energy for the formation of liquidporous medium interface in the pores belonging to the infinite cluster of filled pores. It was found that in dependences on the porosity and, consequently, in dependences on the number of filled pores neighbors, the thermal effect of filling can be either positive or negative and the cycle of infiltration-defiltration can be closed with full outflow of liquid. It can occur under certain relation between percolation properties of porous medium and the energy characteristics of the liquid-porous medium interface and the liquid-gas interface. It is shown that a consecutive account of these correlation effects and percolation properties of the pores space during infiltration allow to describe all experimental data under discussion.

The Effect of Surface Entropy on the Heat of Non-Wetting Liquid Intrusion into Nanopores

“…This movement toward the experimental value is expected when considering the analysis by Laouir et al . 33 and Borman et al ( 36 ) regarding these properties.…”

“…As well, there is also the consideration from Borman et al . 36 about the formation and destruction of the meniscus inside the pore and the process of pore filling. In an amorphous system, the pore system would be difficult to model since the pores can be of different sizes and geometries.…”

“…These liquid properties are linked to the thermodynamic response of both thermal and mechanical energy. A more complex model by Borman et al ( 36 ) used analytical methods with percolation theory as applied to randomly situated spheres. Tersely, the model identified that the exothermic and endothermic behavior of intrusion and extrusion is a combination of surface development, which is related to the surface energy and meniscus formation, which is associated with the temperature dependence of contact angle.…”

Observation of the Anomalously Slow Relaxation of a Nonergodic System of Interacting Liquid Nanoclusters in a Disordered Confinement of a Random Porous Medium

“…The surface tension coefficient of water at = 293 T K is 75 mJ/m 2 [71]. The quantity  and its temperature dependence for the system under study were determined from the temperature dependence of the extrusion pressure by the method described in [57]. The  value at = 293 T K is 22 mJ/m 2 .…”

“…These estimates by Eqs. (6) and (19) with the dependence () T  from [71], as well as  and its temperature dependence determined by the method described in [57], give It follows from Eqs. (4) and (9) that the character of relaxation of the state formed at the reduction of excess pressure to 0 p  is determined by the potential barrier  .…”