Valorisation of corncob residues to functionalised porous carbonaceous materials for the simultaneous esterification/transesterification of waste oils

Functionalised porous carbonaceous materials prepared from the controlled pyrolysis of corncobs were found to provide excellent activities in the simultaneous esterification/transesterification of highly acidic waste oils to biodiesel-like mixtures. Materials carbonised at 600 °C (mostly microporous) containing –SO3H groups (ca. 1 wt% S, 0.16 mmol g−1 –SO3H) exhibited the optimum yields (>95%) to fatty acid methyl esters after 6 h of reaction.