|RAZON, LUIS - De La Salle University|
|DE CASTRO, MARIA - De La Salle University|
Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/6/2015
Publication Date: 3/28/2015
Citation: Knothe, G.H., Razon, L.F., De Castro, M.E. 2015. Methyl esters (biodiesel) from and fatty acid profile of Gliricidia sepium seed oil. Journal of the American Oil Chemists' Society. 92:769-775.
Interpretive Summary: An alternative fuel for diesel fuel made from petroleum is biodiesel. Biodiesel is made from materials such as vegetable oils, animal fats, used cooking oils, or other suitable feedstocks. Since not enough feedstocks of this kind presently exist for biodiesel to replace all petroleum-derived diesel fuel, additional materials need to be identified. In this work, the seed oil of a tree known by its scientific name of Gliricidia sepium was analyzed and examined for its properties. The investigation revealed that the biodiesel made from the seed oil of this tree is suitable for fuel applications, but likely has problems when using it at low temperatures. Thus, the seed oil of Gliricidia sepium may be a suitable biodiesel feedstock in warmer climates.
Technical Abstract: Increasing the supply of biodiesel by defining and developing additional feedstocks is important to overcome the still limited amounts available of this alternative fuel. In this connection, the methyl esters of the seed oil of Gliricidia sepium were synthesized and the significant fuel-related properties determined. The fatty acid profile was also determined with saturated fatty acids comprising slightly more than 35%, 16.5% palmitic, 14.5% stearic, as well as lesser amounts of even longer-chain fatty acids. Linoleic acid is the most prominent acid at about 49%. Corresponding to the high content of saturated fatty acid methyl esters, cold flow is the most problematic property as shown by a high cloud point of slightly > 20°C. Otherwise, the properties of G. sepium methyl esters are acceptable for biodiesel use when comparing them to specifications in biodiesel standards but the problematic cold flow properties would need to be observed. The 1H- and 13C-NMR spectra of G. sepium methyl esters are reported.