While the environmental effects of the Gulf of Mexico oil spill are still showing up, researchers at the University of Michigan have come up with an innovative way to separate oil from water using a “smart filter” that does its job with gravity alone. The smart filter comes with a special coating that manages to repel oil but attract water. These unique properties come courtesy of a rubbery, commercially-available polymer and an advanced nanoparticle. The polymer forms hydrogen bonds with water, thereby attracting it.
The hydrophilic and also oleophobic coating, was coated on postage-stamp-size pieces of window screen and polyester fabric after which the researchers cured the snippets under ultraviolet light. On passing the oil/water mixture through the filters, the researchers found that the material did its job with 99.9 percent efficiency. The affordable approach could easily replace chemical dispersants commonly used to separate oil from water.
The coating creates a filter through which only water can pass and oil remains on the surface. During tests, the research team was able to use these advanced filters for more than 100 hours without showing any signs of clogging. In addition to oil-spill clean-up, the technology could also be used for wastewater treatment and management.