Review of Green Solvents for Oil Extraction from Natural Products Using Different Extraction Methods

Abstract

This paper provides an overview of the use of green solvents for oil extraction from natural product using soxhlet extraction and supercritical fluid extraction (SFE) methods. In terms of qualitative and quantitative determinations on the extracted oils, the use of green solvents was comparable with n-hexane. For soxhlet extraction method, the integration of microwave application into the soxhlet at their optimum conditions has shown improvement in oil yield, oil quality, solvent consumption and extraction time. SFE using CO2also revealed promising results as soxhlet extraction but apparently it involved high operating cost and difficult to control. Despite of that, all the studies successfully demonstrated the suitability of green solvent as an alternative to petroleum driven solvents for extraction of oils from natural products.