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Separating oil-water mixtures is critical in a variety of practical applications, including the treatment of industrial wastewater, oil spill cleanups, as well as the purification of petroleum products. Among various methodologies that have been utilized, membranes are the most attractive technology for separating oil-water emulsions. In recent years, selective wettability membranes have attracted particular attention for oil-water separations. The membrane surfaces with hydrophilic and in-air oleophobic wettability have demonstrated enhanced effectiveness for oil-water separations in comparison with underwater oleophobic membranes. However, developing a hydrophilic and in-air oleophobic surface for a membrane is not a trivial task. The coating delamination process is a critical challenge when applying these membranes for separations. Inspired by the above, in this study we utilize poly(ethylene glycol)diacrylate (PEGDA) and 1H,1H,2H,2H-heptadecafluorodecyl acrylate (F-acrylate) to fabricate a hydrophilic and in-air oleophobic coating on a filter. We utilize methacryloxypropyl trimethoxysilane (MEMO) as an adhesion promoter to enhance the adhesion of the coating to the filter. The filter demonstrates robust oil repellency preventing oil adhesion and oil fouling. Utilizing the filter, gravity-driven and continuous separations of surfactant-stabilized oil-water emulsions are demonstrated. Finally, we demonstrate that the filter can be reused multiple times upon rinsing for further oil-water separations.
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A Micro/Nano Engineering Laboratory Module on Superoleophobic Membranes for Oil-Water Separation
ABSTRACT This article presents a laboratory module developed for undergraduate micro/nano engineering laboratory courses in the mechanical engineering departments at the Massachusetts Institute of Technology and King Fahd University of Petroleum and Minerals. In this laboratory, students fabricate superoleophobic membranes by spray-coating of titania nanoparticles on steel meshes, characterize the surfaces and ability of the membrane to retain oil, and then use these membranes to separate an oil-water mixture. The laboratory module covers nanomaterials, nanomanufacturing, materials characterization, and understanding of the concepts of surface tension and hydrostatics, with oil-water separation as an application. The laboratory experiments are easy to set up based on commercially available tools and materials, which will facilitate implementation of this module in other educational institutions. The significance of oil-water separation in the petroleum industry and integration of concepts from fluid mechanics in the laboratory module will help to illustrate the relevance of nanotechnology to mechanical and materials engineering and its potential to address some of the future societal needs.
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- Award ID(s):
- 1663296
- PAR ID:
- 10028118
- Date Published:
- Journal Name:
- MRS Advances
- Volume:
- 2
- Issue:
- 31-32
- ISSN:
- 2059-8521
- Page Range / eLocation ID:
- 1699 to 1706
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1557/adv.2017.255
