(421h) Magnetically Induced Emulsification and Demulsification of Three-Component Castor Oil/Water/Ethanol Emulsions Stabilized By Cnc@Fe3O4 and Lignin@Fe3O4 Nanocomposites
AIChE Annual Meeting
2021 Annual Meeting
Engineering Sciences and Fundamentals
Emulsions and Foams
Wednesday, November 10, 2021 - 9:30am to 9:45am
The oil to water volume ratios of emulsions was first optimized using a binary castor oil/water system. With oil contents of 70% and 90% v/v, and addition of 1wt% CNC@Fe3O4 NPs of aqueous phase, the emulsions were water-in-oil (W/O) and were broken by an external magnet, while the CNC@Fe3O4 NPs were recovered and recycled. The 30 and 50% v/v oil emulsions were oil-in-water (O/W) and could not be broken by the magnet with CNC@Fe3O4, probably as a consequence of higher emulsion stability. Lignin@Fe3O4, however, broke the emulsions at 50 v/v% using an external magnet. To assess the effect of the CNC@Fe3O4 and lignin@Fe3O4 on the castor oil/water/ethanol Pickering emulsions, stabilized by the nanocomposites, emulsions were formulated by using a 70/30 volume ratio of castor oil rich and water-rich phases with added ethanol at the equilibrium composition. The emulsions were observed to be stable for a long time (at least 48 hours) without the presence of a magnet. Moreover, the composition of CNC@Fe3O4 NPs and lignin@Fe3O4 NPs was varied from 0, 0.1, 0.3, 0.5, and 1 wt% of the aqueous phase. In each case, the emulsions were water-in-oil (W/O) and were broken by an external magnet at equilibrium conditions in less than 24 hours. Emulsions stabilized with the NP concentration of 1 wt% of aqueous phase showed faster magnetic demulsification than the lower NP concentrations. The demulsification capability of the fabricated CNC@Fe3O4 and lignin@Fe3O4 have potential uses for magnetically-driven separations, oil recovery, or drug delivery.