“Instead of boiling mixtures to purify them, why not separate components based on shape and size?”
The membrane resists swelling, a major flaw in earlier versions. It performs well with both light and heavy hydrocarbons.
Borrowing from water desalination
To build the new membrane, the team repurposed a technology from the water industry. Since the 1970s, reverse osmosis membranes have cut desalination energy use by 90 percent.
MIT scientists adapted these membranes to handle crude oil.
They replaced a flexible amide bond with a rigid imine bond, making the film more stable and hydrophobic. This allows hydrocarbons to move quickly through the membrane without causing it to swell.