3.3 Demulsification process
To investigate the demulsification process, the demulsification was
recorded by an inverted microscope. As presented in Fig. 4a , a
lot of floccules formed as soon as contacting with the emulsion. And the
rounded edge of emulsion drop was replaced by the irregular margin of
large floccules. The coalescence for emulsions could occur with
different patterns, such as two points coalescence liking the cell
fusion (Fig. 4b ), three points blend (Fig. 4c )
and multi-point incorporation
(Fig. 4d ). Finally, the coalesced emulsion drops would crack as
shown in the Fig. 4e , releasing the oleic acid. The oleic acid
surrounded the MIL-100(Fe), forming the floccules and floating on the
water as showed in Fig. 2a .