Phase separation of a binary liquid mixture in a porous medium

Abstract

The phase separation of a binary liquid mixture contained in a rigid porous medium has been investigated by study of the light scattered at 90° from a porous glass rod containing a critical mixture of n-${\mathrm{C}}_6$ ${\mathrm{H}}_{14}$+n-${\mathrm{O}}_6$ ${\mathrm{F}}_{14}$. Evidence is found for phase separation at a temperature markedly below the critical temperature of the bulk mixture. Temporal concentration fluctuations in the rod are not observed. The separated phases remain metastable at temperatures well above the bulk critical temperature. These phenomena are in part consistent with a description in terms of a random field.