Oil spills remain a huge environmental problem, but perhaps researchers at Argonne National Laboratory in Illinois may have found the ultimate solution.
They have developed a sponge-like material that absorbs up to 90 times its weight in oil, while being reused up to 100 times. This is by far the fastest and cheapest way to clean up an oil spill.
Present solutions include a floating absorbent material called a sorbent boom, which soaks up oil. However, the most that it can absorb is only 3 to 70 times its weight in oil. That is apart from the fact that it can only be used once – after they absorb enough oil, they are disposed, hence creating a bulk of wastes.
That’s what separates this new sponge-like material of Argonne from the conventional sorbents. In experiments, it was proven have absorbed 90 times its weight in oil and can be used up to 100 times.
It is made of a foam consisting of polyurethane or polyimide plastics with silane molecules as a coat which attracts oil. And the researchers found that the chemical attraction should be just right, meaning that the silane should be in the right amount for the material to be fully functional as an absorber.
In the experiment, the team made an array of square pads of the sponge material measuring around 6 square metres.
“We made a lot of the foam, and then these pieces of foam were placed inside mesh bags – basically laundry bags, with sewn channels to house the foam,” said Seth Darling, one of the researchers at Argonne.
These bags were taken to a large pool specially designed for practicing emergency responses to oil spills, allowing them to absorb crude oil from the water. Spongers were taken out of the bags and sent through a wringer to remove the oil. This process was repeated over multiple days to test the material’s capability.
“Our treated foams did way better than either the untreated foam that we brought or the commercial sorbent,” says Darling.
It is unclear for now, however, if the material can take on the high pressures of the deep sea. This is now being worked on by the researchers as well as the material’s scaling up.
Source: New Scientist