Elaeis guineensis is an edible oleaginous plant known as palm. The rapid increase in the production in the last 20 years has made palm oil the most important oil in the world. It is preferred for its high productivity, which explains its rapid expansion (Rupilius and Ahmad, 2007). Palm kernel oil is extremely important for the oleochemical industry because of the fatty acids profile (Ahmad, 2006). In the past decade, some researchers also found the feasibility of palm oil to produce biodiesel using either homogeneous (Darnoko and Cheryan, 2000; Crabbe et al., 2001) or heterogeneous catalysts (Jitputti et al., 2006).

Comparing the use of diesel fuel to run diesel engines, pure biodiesel exhibits an increase in BSFC up to 17% (Lin et al., 2006), while mixtures of 20% biodiesel with diesel fuel showed a lower increase of 3.3%. Altitude can play an important role, as better engine performance is achieved at high altitudes due to the influence in the duration of the premixed combustion stage (Benjumea et al., 2009). Even biodiesel from waste palm oil causes reductions in CO, HC and smoke opacity, while NOx increases (Ozsezen et al., 2009). The use of additives in 20% biodiesel blends seems to improve the previous results (Kalam and Masjuki, 2008). This oil has also been used straight and preheated, showing no negative effects on the engine, although exhaust emissions increased (Bari et al, 2002). The use of pure oil blended in low percentages with diesel fuel showed no signs of engine deterioration, while engine performance was not affected (Sapaun et al., 1996).