Optimization of oil extraction from Mucuna pruriens seeds (velvet bean) for biodiesel production

There is a need to expand the present supply of oil for biodiesel production by harnessing more non-conventional seed oils. This work reports the production of biodiesel from Mucuna pruriens seed oil for the first time. The seed oil was extracted with n-hexane, refined and characterized according to ASTM standards. The oil was transesterified at a mole ratio of 1:10 of oil to methanol. The oil extraction process was optimized by using the central composite design-based response surface methodology. The oil extraction process indicated maximum yield is 52.97%. The quadratic model obtained for the extraction process predicted 52.99% oil yield with R
²
values of 0.9774. Optimal oil yield is 51.99% was obtained at a temperature of 78 °C, solvent to solid ratio of 4, and time of 35 mins. The fatty acid profile consists mainly of oleic acid (18.31%) and dodecanoinc acid (14.97%). The biodiesel yield of 68.79 % was achieved and fatty acid methyl esters were confirmed on gas chromatography mass spectrophotometer (GC-MS) and Fourier transform Infrared (FTIR) spectrophotometer. The characteristics of the biodiesel produced conformed to ASTM standards.