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Abstract: Alternative, non-food based biomass fuel feedstock development is vital for our national security, economy and the environment. Microalgae are among the most promising of these alternatives. Microalgal cell growth rates and metabolic products are affected by a combination of environmental parameters. In this work, the influences of light source, light intensity, CO2 concentration, and photoperiod on the growth of Dunaliella tertiolecta (D. tertiolecta) were studied. The effects of these environmental parameters on the lipid content and fatty acid composition of D. tertiolecta were also investigated. Red light-emitting diodes (LEDs), white LEDs, and fluorescent lights were all found to be effective for algal growth. Increasing light intensity resulted in significantly more rapid algal growth, and increasing the period of light also significantly increased biomass productivity. Similar growth rates were observed for 2%, 4%, and 6% CO2-concentrations. The different light sources and intensities were found to have no significant effect on FAME composition of D. tertiolecta. Methyl linolenate and methyl palmitate were found to be the major components of FAME produced from D. tertiolecta oil. D. tertiolecta and its derived oils should be a suitable feedstock for biofuel production. [Copyright &y& Elsevier]

Abstract: A quality survey of the biodiesel blends sold in 24 retail stations in March and April 2007 was performed. The main feedstock for the biodiesel blends sold was determined to be soybean oil based. The total acid numbers (TAN) for all of the samples were below 0.3mg/g, and the derived cetane numbers (DCN) were above 40 for all but one of the samples. The viscosity of all the samples was within the proposed ASTM range for B20. The cold-flow properties were adequate, with the pour point (PP) being below −36°C for most samples, suggesting the presence of a pour point depressant. However, the oxidative stability for the samples is of concern, with over 45% having an induction period (IP) of less than 6h. Moreover, the actual blending level of the biodiesel blends generally differed from the blending level on the pump label, and fuel properties varied over a wide range even for the same blend composition. [Copyright &y& Elsevier]