Removing up to 95% of oil-spill of different densities — light and heavy oils — repetitively at least 100 times using superhydrophobic (extremely water repelling) medical cotton has been demonstrated by a team of researchers led from the Department of Chemistry at the Indian Institute of Technology (IIT) Guwahati.
- The medical cotton, which is extremely water absorbing, was turned into a superhydrophobic material, which is extremely water repellent and has water contact angle of 157 degrees.
- The absorption efficiency of the superhydrophobic cotton was very high, which meant that one gram of the superhydrophobic cotton absorbed 20 grams of either heavy or light oils.
- The other important characteristic is its ability to absorb oil from three complex phases – light oil that floats in the air-water interface, sediment oil that settles at the bottom as it is heavy, and from the water-in-oil emulsion.
- It is important to note that the cotton, however, cannot remove oil efficiently from the oil-in-water emulsion but can do so from the water-in-oil emulsion.