A smart sponge will help to quickly and cheaply clean up oil spills and other oily substances. The development of scientists from Northwestern University of the United States is described in the journal Industrial Engineering and Chemical Research.
Oil spills have a devastating effect on the marine environment – birds caught in the spill cannot take off and die. Now cleaning up spills is a complex and expensive process, in which chemical dispersants are used to break down oil into very small drops, as well as degreasing oily substances and absorbing them with expensive, unsuitable for reuse sorbents.
The sponge developed by scientists is a nanocomposite coating of magnetic nanostructures on a carbon substrate, which is oleophobic (attracts oil), hydrophobic (repels water) and magnetic.
The nanoporous three-dimensional structure of the nanocomposite selectively interacts with molecules of an oily substance and binds to them, trapping and storing them until it is squeezed out. Magnetic nanostructures endow a smart sponge with two additional functions: controlled movement in the presence of an external magnetic field and desorption of adsorbed components.
Researchers note that the coating, which is the basis of development, can be applied to any sponge. It will allow the sponge to nourish 30% more oily matter than its own weight. And after squeezing it remains no more than 1% of the absorbed oil.