Recovery of microalgae biodiesel using liquid biphasic flotation system

Abstract

Exponential increase of greenhouse gases has raise a global concern. More than a quarter of the greenhouse gases (e.g. carbon dioxide) are released from the transportation sector driven by the burning of vehicle fuel. Biofuel was introduced to limit the emission of greenhouse gases due to its potential to cut the emissions by up to 86 %. Microalgae have shown to be a suitable biomass for the production of biofuel because they are rich in biomolecules such as lipid. This study focuses on the extraction of natural lipid from Chlorella sorokiniana CY-1 for biodiesel production using liquid biphasic flotation (LBF) system. LBF system is a novel environmentally friendly method used for biomolecules extraction from microalgae. It is an integration of aqueous two-phase system with mass transfer mode of solvent sublation that eases the transfer of biomolecules from the bottom phase to the top phase. The study unveils the potential of the LBF system to recover up to 74.44 % lipid using 100 % (v/v) ethanol and ammonium sulphate in 20 min time. GC-FID confirmed the successful extraction of lipid from the microalgae. Three peaks of fatty acid methyl ester, mainly from the middle chains (C5:0) (C12:0) and (C20:0) were observed, expending new opportunity for microalgae biodiesel technology.