Preparation of biodiesel from Jatropha curcas L. oil produced by two-phase solvent extraction

In the present work the preparation of biodiesel from Jatropha curcas L. oil produced by two-phase solvent extraction (TSE) was studied. The experimental results of TSE process showed that the optimal extraction conditions were 30 g samples, 240 mL of extraction solvent mixture and methanol/n-hexane volume ratio 60:40, extraction temperature 35 °C, extraction time 30 min. Further, the effect of methanol recycling on the TSE process was also investigated. After TSE process, the investigations were carried out on transesterification of methanol with oil–n-hexane solution coming from TSE process in the presence of sodium hydroxide as the catalyst. The conversion could achieve 98% with 3:1 n-hexane/oil weight ratio, 60 °C reaction temperature, 7:1 methanol/oil mole ratio, 1.1% alkali catalyst concentration and 120 min reaction time. The properties of fatty acid methyl ester (FAME) product prepared from Jatropha curcas L. oil produced by two-phase solvent extraction met the ASTM specifications for biodiesel.