In situ Transesterification of Microalgal Oil to Produce Algal Biodiesel

2012Final Report; Aug. 2011-June 2012PDFTech ReportKLK768N12-10DTRT07-G-0056Fuel compositionAlternate fuelsFuel processingDiesel fuelsBiodiesel fuelsAlgaeBiodiesel fuelsMicroalgaeFuel processingResearch HubIdahoUnited StatesNational Institute for Advanced Transportation Technology (U.S.)He, B. BrianNational Institute for Advanced Transportation Technology (U.S.)United States. Dept. of Transportation. Research and Special Programs AdministrationNTL-ENERGY AND ENVIRONMENT-Alternative FuelsUS Transportation CollectionThis research was to process whole microalgae cells for biodiesel production without first extracting lipids. The ultimate goal is develop a novel process for algal biodiesel production directly from microalgae cells in a single step, i.e., in situ transesterification, to lower the processing costs. In this stage, we conducted research on (1) characterizing the selected microalgae strains and (2) screening the influential process parameters. Characterization was performed on microalgae through proximate and ultimate analyses, fatty acid profiles, ash content and mineral components of the microalgae samples, Thermogravimetric analysis and scanning electron microscopy examination on the samples. It was found that green microalgae are suitable for algal biodiesel production due to their relatively high lipid content, while brown microalgae may be good for fermentable sugar production due to their high carbohydrate content. Microalgae tested in this study have relatively high ash content (up to 25%wt), which is somewhat unexpected. Fatty acid profiles varied widely among the microalgae tested and need validation through further investigation. Reaction time affected the microalgal lipid conversion considerably at 300\ub0C, and extending the reaction would lead to satisfactory process efficiency. Findings from this study provide necessary information for the continued systematic investigation on algal biodiesel production