Augustana College, Chemistry, Rock Island, IL 61201
Biodiesel, a promising renewable fuel consisting of the alkyl esters of fatty acids, can be synthesized via the transesterification of various vegetable oils with low molecular weight alcohols in the presence of either acidic or alkaline catalysts. Nanocrystalline metal oxides have shown promising catalytic activity in this and other reactions, and with this in mind, further investigations using MgO, Al2O3, and TiO2 have been carried out. MgO showed strong catalytic activity, in accordance with its status as the strongest base of the three. Al2O3, a weak acid, failed to catalyze the reaction in any significant way, and TiO2, a weak base, showed only very limited catalytic ability. The MgO catalyst requires higher temperatures and longer reaction time to achieve high yields, but may be reusable.
[Abstract (DOC)]