  High pressure water intrusion in hydrophobic nanoporous media have been
studied in relation with energy storage. It has already been showed that
addition of electrolytes in water increases intrusion pressure of liquid
leading to an enhancement of storing capacities. We demonstrate here that for a
number of salt, a very simple van't Hoff law can explain intrusion and
extrusion excess pressures compared with the pure water case. Our results
suggest that only pure water can penetrate the pores, the ions being quartered
in the bulk liquid around nanoporous medium. This selectivity explains very
high pressures for very concentrated ions reported by Tzanis et al (2014).
Finally, a partial intrusion of NaI and LiI is observed. This effect could be
explained on the basis of particular behaviour or iodide ions over hydrophobic
surfaces.
