The effect of high oleic and linoleic fatty acid composition for quality and economical of biodiesel from crude Calophyllum inophyllum oil (CCIO) with microwave-assisted extraction (MAE), batchwise solvent extraction (BSE), and combination of MAE–BSE methods

Indonesia is very much dependent on fossil fuel for its energy source, but has recently been promoting renewable energy resources capable of simultaneously balancing economic and social development with environmental protection. Biodiesel is one of the renewable energies that currently been promoted frequently uses edible oil as its feedstocks. One of the promising non-edible oil crop is crude Calophyllum inophyllum oil (CCIO). It has a high oil content, composed of mostly triglycerides (TG) that resulted in a higher yield of biodiesel. Previous researches were limited to its conversion into biodiesel with desired quality and economical. In this work, the time of extraction and fatty acid composition were investigated. Batchwise solvent extraction (BSE), microwave-assisted extraction (MAE), and MAE–BSE combination were applied to achieve purified CCIO in a shorter amount of time. For BSE, MAE and MAE–BSE combination, it was found free fatty acids (FFA) content was decreased from 15.07 ± 0.141 to 1.045 ± 0.215%, 6.91% ± 0.04%, and 1.10 ± 0.141%, respectively. Moreover, TG content was increased significantly from 67.25 ± 0.372 % to 94.95 ± 0.005%, 84.45%±0.37%, and 96.062% ± 0.035%, respectively. The majority of fatty acid composition for the MAE and combination method is linoleic acid with 46.36% and 45.43%, respectively. While the BSE method's majority fatty acid composition is oleic acid with 32.90%. All results were converted as biodiesel using the transesterification method. The quality of biodiesel was graded using density, acid value, and cetane number as the parameters. The various result of biodiesel was evaluated by the American society for testing materials (ASTM D6751-2), the European Union (EN 14214-03) and SNI 7182:2015 standard procedures. Based on all three parameters, the biodiesel resulting from the BSE purification methods fit all parameters according to the existing standard.