Suppression effect of liquid composition on defiltration of nanofluids in lyophobic environment

Understanding nanofluidic behaviours in energetically unfavourable confining environments is essential for the development of high-performance nanoporous energy absorption systems. In the current study, the effect of liquid composition on defiltration in a hydrophobic nanoporous silica gel is investigated experimentally using two types of admixtures: carbamide of a relatively small molecular size and sodium bis(2-ethylhexyl) sulfosuccinate of a relatively large molecular size. By adding carbamide in the liquid phase, while the change in the solid–liquid interfacial tension is secondary, the defiltration volume can be lowered significantly, which can be related to the difficulties in gas phase formation and growth in nanopores. The factor of sodium bis(2-ethylhexyl) sulfosuccinate comes in mostly by affecting the liquid motions in relatively small nanopores.