MICROALGAE AS FEEDSTOCK FOR BIODIESEL PRODUCTION: Carbon dioxide sequestration, lipid production and biofuel quality

The objective of this paper was to evaluate the carbon dioxide sequestration capacity, biomass production, lipid content, lipid productivity and biodiesel quality of six microalgal strains cultivated photosynthetically in a bubble column photobioreactor. Lipid productivity was the criteria for selection species; for the best specie, carbon dioxide sequestration rates, biomass productivity, lipid content and lipid productivity of 17.8 mg/L . min, 20.1 mg/L . h, 27.0% and 5.3 mg/L . h were obtained. Qualitative analysis of the fatty acid methyl esters demonstrates the predominance on saturated (43.5%) and monounsaturated (41.9%) fatty acids. The critical parameters for quality properties of biodiesel evaluated (ester content, 99.85%; cetane number, 56.73; iodine value, 65.00 gI(2)/100 g; degree of unsaturation, 74.07% and cold filter plugging point, 4.54 degrees C) comply with the US Standard (ASTM 6751), European Standard (EN 14214), Brazilian National Petroleum Agency (ANP 255) and Australian Standard for biodiesel. The novelty of this paper is the estimation of the fuel properties of the microalgal biodiesel and the comparative study of conventional sources used as feedstock for biodiesel manufacture, facilitating worldwide advances in this research area.