Pilot-scale supercritical carbon dioxide extractions for the recovery of triacylglycerols from microalgae: a practical tool for algal biofuels research

摘要: We describe the preliminary extractions from a pilot-scale supercritical carbon dioxide (SC-CO2) extractor for isolation of algal lipids suitable small-scale conversion to liquid hydrocarbon fuels. Flowable oils were recovered SC-CO2 lyophilized Nannochloropsis granulata. The extracted determined be composed primarily triacylglycerols (TAG) by chromatography–mass spectrometry analysis. Gravimetric lipid yield was increased significantly 15.56 28.45 mg g−1 ash-free dry weight (AFDW) with an increase in temperature 50°C 70°C, at 35 MPa over 270 min. Varying pressure had no significant effect on yield. Liquid analysis SC-SO2 extracts indicated that TAG profile remained constant regardless extraction pressure, and fatty acid methyl esters (FAME) revealed uniform throughout all conditions. Our optimized gravimetric yields N. granulata (28.45 mg g−1 AFDW) approximately half obtained Soxhlet hexane (57.53 mg g−1 AFDW); however, FAME similar technique (18.23 mg FAME g−1 17.35 mg AFDW extraction, respectively). Further Botryococcus braunii as efficient extraction. These results highlight suitability large-scale oil microalgae biofuel or biojet analyses due its selectivity