Nanosponges
Monday 16 April 2012
A sponge that can absorb 100 times its own weight in oil. This novel way to clean up oil spillage using carbon nanotubes has recently been reported in Scientific Reports by a team working at Rice University. Nanotechnology is one of the topics on the IB Option C; Chemistry in industry and technology and this latest discovery neatly overlaps with the environmental issues of cleaning water contaminated by oil spillage. What the team at Rice has managed to do is ‘weld’ carbon nanotubes together using boron to form covalent linkages. The resulting three-dimensional blocks, which contain billions of nanotubes, can act like sponges as they contain more than 99% air. They are also able to conduct electricity and be manipulated by magnets. The blocks repel water (hydrophobic) but are extremely oleophilic – i.e. they 'love' oil and 'hate' water. Because of their low density they can float on water and absorb spilled oil. What is even more remarkable is that the process is reversible. The oil can either be stored for later use or burned off leaving the ‘sponge’ able to soak up more oil. A video has been produced on You Tube which shows this process. If these blocks can be made on an industrial scale then they have enormous potential to clean up oil spillage wherever it may occur.