Biodiesel is a renewable biofuel that is nowadays a real alternative to fossil diesel. Its use has several
environmental benefits related to the decrease of CO2 emissions as well as several other air
pollutants. Biodiesel is mainly produced by a transesterification reaction where the oils or fats react
with a short chain alcohol, usually methanol, in the presence of a catalyst. At an industrial scale
homogeneous alkaline catalysts, such as sodium or potassium hydroxide or methoxyde, are usually
used. The aim of this work is to study the use of crude and heated palm oil with a high content of
free fatty acids (13 – 18 mgKOH/g) as feedstock for biodiesel production. The high content of free
fatty acids (FFA) makes this type of oil inadequate for the use in an alkaline catalyzed
transesterification reaction without a pre‐treatment. Therefore, an acid catalyzed esterification
reaction was carried out to reduce the acidity before the transesterification reaction. In this study,
the methanol:oil molar ratio was optimized. The results show that using palm oil as feedstock it is
possible to produce a biodiesel with a fatty acids methyl esters content higher than 96.5%, which is
the minimum values imposed by the international standards. Furthermore, the heating of the oil at
150ºC for 20 min did not significantly affect the yield of the transesterification reaction and the
density, viscosity and refractive index of biodiesel.