Biodiesel production in the European Union was over
7.7 million tons in 2008, 35.7% more than in 2007 [6]. It is
estimated that in 2010 biodiesel demand may increase to 10
million tons per year [7]. Currently, methyl or ethyl esters
of fatty acids produced by transestrification from vegetable
oil are the most widely used biodiesel fuels [8]. For every 3
moles of ethyl esters 1 mol of crude glycerol is produced
[9]. If biodiesel production increases as predicted, the supply
of crude glycerol will pose a serious problem, its utilization
will become an urgent topic. Biodiesel producers
have limited funds to refine this by-product and, since it
contains methanol, it is considered a hazardous waste.