Several attempts have been made to combine the unique characteristics of graphene oxide
(GO) and commercial polymers for successfully designing and fabricating next-generation
membranes in filtration and separation technologies.
The first part of the work develops a high flux polyethersulfone ultrafiltration membranes,
by embedding GO sheets, starting from the polymer/GO solutions in ionic liquid and N, N
dimethylformamide as co-solvents and promoting the pore formation via non-solvent
induced phase separation. In the second part of the work, a protic ionic liquid was
introduced as a solvent to disperse GO sheets and fabricate GO liquid crystal membranes
for nanofiltration. The third part addresses the stability enhancement. GO membranes
frequently disintegrate in aqueous environments due to swelling. Ethylenediamine was
then used as a crosslinker, and the membranes were tested for organic solvent
nanofiltration. Additionally, overcoming the permeation-rejection trade-off is challenging.
Hence, the fourth work involved the intercalation of silica nanoparticles to form dual-sized
nanochannels. In the final work, GO membranes were fabricated on the surface of hollow
fibers to overcome scalability issues, by using a feasible spray coating method for efficient
nanofiltration. Hollow fibers were crosslinked with hexamethylene diamine and GO was
spray-coated on the crosslinked polymeric fibers for organic solvent nanofiltration.
Overall, this study demonstrates the potential of GO in developing high-performance
membranes for liquid separations relevant for industrial applications, such as wastewater
treatment, food, chemical, petrochemical, and pharmaceutical processing.
|Date of Award||Nov 2019|
|Original language||English (US)|
- Biological, Environmental Science and Engineering
|Supervisor||Suzana Nunes (Supervisor)|
- Graphene Oxide
- Liquid Separations
- Organic Solvent Nanofiltration