Researchers at Texas A&M University have developed a non-toxic method of cleaning up residual crude oil following a spill. LiveScience reports that the team designed nanoparticles that can soak up underwater oil “like millions of tiny sponges.”
Called “nano-sponges,” each nanoparticle can soak up more than 10 times its own weight in oil and is 100 times thinner than a human hair. The nanoparticles are coated with a polymer that absorbs crude oil – a mixture of Styrofoam and the absorbent material found in baby diapers.
And, perhaps best of all, the nano-sponges can be removed from the water after they’ve done their job, and can be reused after the oil is removed. Nano-sponges have a magnetic iron oxide core, which allows for a magnetic device to be passed over the surface of the water and collect the tiny super sponges.
The swollen nanoparticles can then be washed in concentrated grain alcohol, or ethanol, in order to remove the oil. Washing results in fresh nanoparticles that can be continually recycled. The research team estimates the cost of their devices is comparable to current clean-up methods.
“When I was a Ph.D. student, I remember reading about sludge in the Hudson River,” the project’s lead researcher, chemist Karen Wooley, told LiveScience. “Even back then, I was imagining particles that could be dispersed and sunk to the bottom, take in the sludge and float back to the top.”
Wooley’s team simulated the Deepwater Horizon oil spill to demonstrate that their devices will work in real-world situations.
During the 2010 Gulf oil spill, BP elected to use millions of gallons of the toxic dispersant Corexit to hide and disperse the massive amounts of spilled oil. The dispersants contained solvents such a petroleum distillates and 2-butoxyethanol, and continue to pose a health threat to humans, animals, and the environment.
Some research suggests that BP’s use of Corexit caused more damage to human health and the environment than did the spill the spill itself.
Should future environmental disasters arise, Wooley and her team’s innovative nanoparticles could provide a safe and much more efficient solution to clean-up efforts.
Because the nanoparticles are too small to be seen with the naked eye, soaking up extensive amounts of oil would require a large amount of the sponges. However, they could certainly be used in conjunction with other clean-up methods such as skimming.
Researchers also said that while their devices are non-toxic, they are not biodegradable, meaning if any were left in the environment, they would remain there. “If there are some particles that aren’t captured and recovered, it may be better to have particles made of degradable polymers,” Wooley said.
Her team is now looking into natural polymers like sugar, which can dissolve harmlessly into the environment if left behind.