Dr A Ganesh of IIT-Bombay has synthesized a nanocarbon structures from cashew nut shell by pyrolysis vapours. On heating the cashew nut shells (CNS), an agroindustrial residue, upto about 100oC, the pericardium fluid present in the shells oozes out and is collected (about 14-16% by weight). This is generally used for making resins and adhesives.
The partially de-oiled cashew nut shells are further heated up to about 280 degrees C to remove gases like carbon dioxide, carbon monoxide and water vapour. Subsequent heating of the shells up to about 500 degrees C produces pyrolysis vapours which are condensed to recover oil rich in cardanol.
In a relate project, Dr Ganesh has also developed a method of making aligned rope like nanocarbon structures with platelet like carbon units from cashew nut shell pyrolysis vapours. The method comprises cracking the pyrolysis vapours at 750°C to 900°C and at atmospheric pressure over a supported bimetallic catalyst comprising Co-Ni supported on silica and purifying the nanocarbon structures formed with an acid.
