Fig.
5 Model for oleic acid permeates
horizontally on the water wetted MIL-100(Fe)
Furthermore, the wettability of used MIL-100(Fe) was studied. With
pressing continuously, the water drop was deformative and rolled on the
plane of used MIL-100(Fe) (Fig. 6a~e ).
Additionally, the static water contact angle (WCA) of used MIL-100(Fe)
was up to 179° (Fig. 6f ). Those characteristics of used
MIL-100(Fe) suggested that the wettability of used MIL-100(Fe) has
changed from amphipathicity to hydrophobicity, and the force of adhere
for water on the used MIL-100(Fe) was extremely weak. The hydrophobicity
was disadvantage for the contact between the used MIL-100(Fe) and
emulsion drops. Therefore, the demulsification performance of used
MIL-100(Fe) decreased dramatically (Fig.
3d ).