Sustainable biodiesel production can be realised by the use of a low-cost feedstock, efficient energy and renewable raw materials. The simultaneous Calophyllum oil-resin extraction and its purification using a binary solvent (n-hexane mixed with alcohol) were examined to meet those aspects. The extraction conditions effect was investigated to determine the optimal oil yield and quality. n-Hexane mixed with alcohol was extracted and purified effectively the oil from Calophyllum seeds. The oil yield and its quality were mainly affected by the n-hexane-to-alcohol ratio. The oil yield enhanced as the n-hexane-to-alcohol ratio enlarged from 1:1 to 2.5:1. The acid value and density of the oil improved as the n-hexane-to-alcohol ratio declined from 2.5:1 to 1:1. The n-Hexane-to-alcohol ratio of 2.5:1 provided the best yield (59%) of the oil extracted at 40°C for 5 hours. The oil presented its best quality at 0.893 g·cm<sup>–3</sup> of density, 41.0 mPa·s of viscosity, 8.8 mg KOH·g<sup>–1</sup> of the acid value, 88.3 g per 100 g of the iodine value, < 1% of moisture content and < 0.04% of ash content. The oil also had an inhibitory activity against Staphylococcus aureus.
A binary solvent for the simultaneous Calophyllum oil-resin extraction and purification