Study On Lipid Extraction From Chlorella For Production Of Biodiesel

The search for sustainable and renewable fuels is becoming increasingly important as a direct result of climate change and rising fossil-fuel prices. Microalgae are currently to be one of the most romising alternative sources for biodiesel. Their high photosynthetic rates, often ascribed to their simplistic unicellular structures, enable microalgae not only to serve as an effective carbon sequestration platform but also to rapidly accumulate lipids in their biomass. There are, however, various technological and economic obstacles which have to be overcome before industrial-scale production of microalgae biodiesel can take place. The development of an effective and energetically efficient lipid extraction process from the microalgal cells is critical for the successful upscaling of the downstream processes.This paper attempts to address the knowledge gap surrounding chlorella lipid extraction by summarizing recent studies in the field. Chlorella powder and suspension are regarded as study objects. The contents of sorts of biodiesel were analysed by a gas chromatograph (GC). Extract mass spectra was obtained by ionization time-of-flight (MALDI-TOF) techniques. Chlorella cells after extraction were inspected under a transmission electron microscope (JEM-1400, HITACHI) in order to analysis the mechanism on breaking cell wall.To combine the the abilities of lipids extraction and CO2capture by algae+ionic liquid (IL) system, chlorella hydrolyzed by ILs ([BMIM]BF4,[BMIM]CL and [AMIM]CL) to extract lipids energy-efficiently was demonstrated integrated CO2removal by ILs in this study. Because the energy required by CO2capture in this innovating process was low, and this saved energy could be compensated to lipid extraction. The rate of fuel production/energy consumption is12.35NEG,2.9-5.74time of that of solvent system,1.31time of that of ionic liquid without CO2capture.Furthermore, the energy balance can be improved and the net energy gain (NEG) up to9.41and12.35can be reached by energy compensated from CO2capture.To use the abilities of IL on extraction and CO2capture is an effective and energetically efficient way to get chlorella lipid. The study provides a new approach on lipid extraction for industrial-scale production of microalgae biodiesel.