Swietenia mahagoni seed oil: A new source for biodiesel production

• Oil contains oleic, linoleic, linolenic, palmitic and stearic as major fatty acids.
• Biodiesel prepared using esterification followed by transesterification reactions.
• The resultant biodiesel was evaluated for physico-chemical properties.
• The properties were found to be within in the range of ASTM and EN specifications.

Swietenia mahagoni seed oil contains common unsaturated fatty acids such as oleic (25.5%), linoleic (32.6%), linolenic (12.2%) and saturated fatty acids, namely, palmitic (13.0%) and stearic (14.1%) as major fatty acids with 58.1% oil content. In the present study, the oil with 1.39% free fatty acids was converted into biodiesel employing conventional acid-catalyzed esterification followed by base-catalyzed transesterification reaction. The resultant biodiesel was evaluated for physico-chemical properties namely iodine value (104.6), free fatty acids (0.05%), phosphorous content (0 ppm), flash point (165.0 °C), cloud point (7 °C), pour point (9 °C), viscosity at 40 °C (4.13 cSt), oxidative stability at 110 °C (3.7 h), density (0.880 g/cm3 at 15 °C), and trace metals (Group I metals, 0.5 ppm). The physico-chemical properties were found to be within the range of ASTM and almost falling in the range of EN biodiesel specifications.