posted on 2018-12-11, 15:37authored byGiuseppe Di Vitantonio, Tiancheng Wang, Martin F. Haase, Kathleen J. Stebe, Daeyeon Lee
Pickering emulsions
have been successfully used as media for catalysis
and separation. However, simultaneous reaction and separation cannot
be performed in a continuous mode in these systems, because reagents
cannot be readily loaded into or recovered from the dispersed phase.
Bicontinuous interfacially jammed emulsion gels (bijels), in which
the oil and water phases are continuous throughout the structure,
have potential as media for simultaneous reaction and separation in
a continuous mode. In this work, we take a major step toward realizing
this vision by demonstrating the ability of bijels to be used in reactive
separation performed in a batch fashion. To perform effectively, bijels
must maintain their morphology and interfacial mass transfer properties
during reaction. To strengthen the bijels, we modify the solvent transfer-induced
phase separation (STRIPS) method to make bijels resistant to mechanical
stresses and prevent detachment of nanoparticles from the oil/water
interface due to pH changes by chemically fusing the interfacial nanoparticles.
The reinforced bijel is successfully tested in base-catalyzed hydrolysis
of esters and remains robust under these challenging conditions.