Among many potential applications, carbon nanotubes are great candidate materials for cleaning polluted water. Many water pollutants have very high affinity for carbon nanotubes and pollutants could be removed from contaminated water by filters made of this nanomaterial, for example water soluble drugs which can hardly be separated from water by activated carbon.
Carbon nanotubes are an example of these new materials and consist of cylindrical molecules of carbon with diameters of a few nanometers — one nanometer is one millionth of a millimeter. Carbon nanotubes possess exceptional electronic, mechanical and chemical properties, for example they can be used to clean polluted water. Problems due to filters’ saturation could be reduced as carbon nanotubes have a very large surface area (e.g. 500 m2 per gram of nanotube) and consequently a very high capacity to retain pollutants. “Maintenance and wastes related to water depollution could thus be reduced,” says Thilo Hofmann, Vice Dean of the Faculty of Earth Sciences, Geography and Astronomy of the University of Vienna.