Membrane Separates Oil And Water With Ease

Oil and water usually don’t mix, but when the two end up together, say in an oil spill or in an emulsion, they can be nearly impossible to completely separate. But by combining a water-loving polymer with an oil-repelling silicon-based material, researchers have created a new breed of membrane that can separate bulk amounts of any type of oil-water mixture by simple gravity filtration.

The scientific team that created the hygro-responsive membrane, as it is called, believes it will become an energy-efficient, cost-effective means of cleaning up oil spills.

Traditional membrane-based filtration systems are energy-intensive because the targeted mixture typically must be pumped through the membrane for efficient separation. These membranes are subject to fouling by viscous materials such as oil, lose their effectiveness over time, and typically aren’t versatile enough to separate all types of oil-water mixtures, which range from oil and water layers to surfactant-laden emulsions.

A team led by materials scientist Anish Tuteja of the University of Michigan has devised membranes that for the first time sidestep such limitations (Nat. Commun., DOI: 10.1038/ncomms2027). Arun K. Kota in Tuteja’s group prepared the membranes by dipping polyester fabric or stainless steel mesh into a mixture of cross-linked polyethylene glycol diacrylate, which is hydrophilic, and fluorodecyl polyhedral oligomeric silsesquioxane, which is oleophobic.

Read more: http://cen.acs.org/articles/90/i36/Membrane-Separates-Oil-Water-Ease.html