Researchers from Case Western Reserve University have designed an ultra-lightweight sponge made of clay and a bit of high-grade plastic they say will effectively clean up spills of all kinds of oils and solvents, and allow for the absorbed oil to be squeezed back out for use.
The new material, called aerogel, is made by mixing clay with a polymer and water in a blender. The mixture is then freeze-dried; air fills the gaps left by the loss of water, and the resulting material is super light, comprised of about 96 percent air, 2 percent polymer and 2 percent clay.
The oil-absorbing form is just one of a growing list of clay-based aerogels the researchers are experimenting with. By adding different polymers, they produce materials with different properties. "This particular one is oleophilic or oil-loving," said David Schiraldi, chairman of the Macromolecular Science and Engineering department at the Case School of Engineering. "Chemically, it hates water, loves oil: the perfect combination."
The aeorgel can be made in granular form, in sheets or in blocks of almost any shape and is effective in fresh and saltwater or on a surface. Because absorption is a physical phenomenon, there is no chemical reaction between the material and oil. If the oil is otherwise not contaminated, it can be used. Oil spill experts on both coasts say that the ability to squeeze out and conserve the oil is an advantage over other products currently available.
