MIT researchers think they have found a way to separate oil from water after a major spill. Their newly developed membrane could process large quantities of the finely mixed materials back into pure oil and water.
In addition to its possible role in cleaning up spills, the new method could also be used for routine drilling, such as in the deep ocean as well as on land, where water is injected into wells to help force oil out of deep rock formations.
If you look back at the 2010 Deepwater Horizon oil spill in the Gulf of Mexico you might remember stories and huge quantities of dispersants and de-emulsifiers being dumped into the sea to help with the clean up. Rather than separating the oil from the water , the oil disappeared, hidden in the water, in these what are called fine emulsions. That’s damaging to the environment and so are many of the chemicals used in the Gulf.
The new approach developed by MIT professor Kripa Varanasi, graduate student Brian Solomon, and postdoc M. Nasim Hyder uses membranes with hierarchical pore structures. The membranes combine a very thin layer of nanopores with a thicker layer of micropores to limit the passage of unwanted material. The membranes can be made with contrasting wetting properties so their pores either attract oil and repel water, or vice versa.
“This allows one material to pass while blocking the other with little flow resistance,” Varanasi says.
The team is working with Shell, which supported the research.