In recent years, microalgae-based carbon-neutral biofuels (i.e., biodiesel) have gained considerable interest due to high growth rate and higher lipid productivity of microalgae during the whole year, delivering continuous biomass production as compared to vegetable-based feedstocks. Therefore, biodiesel was synthesized from three different microalgal species, namely Tetraselmis sp. (Chlorophyta) and Nannochloropsis oculata and Phaeodactylum tricornutum (Heterokontophyta), and the fuel properties of the biodiesel were analytically determined, unlike most studies which rely on estimates based on the lipid profile of the microalgae. These include density, kinematic viscosity, total and free glycerol, and high heating value (HHV), while cetane number (CN) and cold filter plugging point (CFPP) were estimated based on the fatty acid methyl ester profile of the biodiesel samples instead of the lipid profile of the microalgae. Most biodiesel properties abide by the ASTM D6751 and the EN 14214 specifications, although none of the biodiesel samples met the minimum CN or the maximum content of polyunsaturated fatty acids with ≥4 double bonds as required by the EN 14214 reference value. On the other hand, bomb calorimetric experiments revealed that the heat of combustion of all samples was on the upper limit expected for biodiesel fuels, actually being close to that of petrodiesel. Post-production processing may overcome the aforementioned limitations, enabling the production of biodiesel with high HHV obtained from lipids present in these microalgae.
This is a preview of subscription content, log in to check access.
K.N.G. (SFRH/BPD/81882/2011) and H.P. (SFRH/BD/105541/2014) are, respectively, a post-doctoral researcher and a PhD student funded by the Portuguese Foundation for Science and Technology (FCT). The work was conducted under projects also funded by FCT and the Portuguese national budget (Projects PEst-OE/QUI/UI0100/2013, PEst-OE/QUI/UI0612/2013, PEst-C/MAR/LA0015/2013, and PEst-OE/EQB/LA0023/2013).
The authors would like to acknowledge the NECTON S.A., Portugal, for providing microalgal samples.
Amaro HM, Macedo AC, Malcata FX (2012) Microalgae: an alternative as sustainable source of biofuels? Energy 44:158–166CrossRefGoogle Scholar
Boundy B, Diegel SW, Wright L, Davis SC (2011) Biomass energy data book, 4th edn. Oak Ridge National Laboratory, US-DOE, Oak RidgeCrossRefGoogle Scholar
Bucy H, Marchese AJ (2012) Oxidative stability of algae derived methyl esters. J Eng Gas Turbines Power 134:092805-092805-13. doi:10.1115/1.4006712
Carvalho AP, Malcata FX (2005) Preparation of fatty acid methyl esters for gas-chromatographic analysis of marine lipids: insight studies. J Agric Food Chem 53:5049–5059CrossRefPubMedGoogle Scholar
Changdong S, Azevedo JLT (2005) Estimating the higher heating value of biomass fuels from basic analysis data. Biomass Bioenergy 28:499–507CrossRefGoogle Scholar
Chen L, Liu T, Zhang W, Chen X, Wang J (2012) Biodiesel production from algal oil high in free fatty acids by two-step catalytic conversion. Bioresour Technol 111:208–214CrossRefPubMedGoogle Scholar
Chisti Y, Yan J (2011) Energy from algae: current status and future trends algal biofuels—a status report. Appl Energy 88:3277–3279CrossRefGoogle Scholar
Daroch M, Geng S, Wang G (2013) Recent advances in liquid biofuel production from algal feedstocks. Appl Energy 102:1371–1381CrossRefGoogle Scholar
Demirbas A (2008) Relationships derived from physical properties of vegetable oil and biodiesel fuels. Fuel 87:1743–1748CrossRefGoogle Scholar
Fassinou WF (2012) Higher heating value (HHV) of vegetable oils, fats and biodiesels evaluation based on their pure fatty acids HHV. Energy 45:798–805CrossRefGoogle Scholar
Hoekman SK, Broch A, Robbins C, Ceniceros E, Natarajan M (2012) Review of biodiesel composition, properties, and specifications. Renew Sust Energ Rev 16:143–169CrossRefGoogle Scholar
Hu C, Li M, Li J, Zhu Q, Liu Z (2008a) Variation of lipid and fatty acid compositions of the marine microalga Pavlova viridis (Prymnesiophyceae) under laboratory and outdoor culture conditions. World J Microbiol Biotechnol 24:1209–1214CrossRefGoogle Scholar
Hu Q, Sommerfeld M, Jarvis E, Ghirardi M, Posewitz M, Seibert M, Darzins A (2008b) Microalgal triacylglycerols as feedstocks for biofuel production: perspectives and advances. Plant J 54:621–639CrossRefPubMedGoogle Scholar
Huerlimann R, de Nys R, Heimann K (2010) Growth, lipid content, productivity, and fatty acid composition of tropical microalgae for scale-up production. Biotechnol Bioeng 107:245–257CrossRefPubMedGoogle Scholar
Jang ES, Jung MY, Min DB (2005) Hydrogenation for low trans and high conjugated fatty acids. Compens Rev Food Sci Saf 4:22–30CrossRefGoogle Scholar
Knothe G (2002) Structure indices in FA chemistry. How relevant is the iodine value? J Am Oil Chem Soc 79:847–854CrossRefGoogle Scholar
Knothe G (2006) Analyzing biodiesel: standards and other methods. J Am Oil Chem Soc 83:823–833CrossRefGoogle Scholar
Knothe G (2007) Some aspects of biodiesel oxidative stability. Fuel Process Technol 88:669–677CrossRefGoogle Scholar
Knothe G (2011) A technical evaluation of biodiesel from vegetable oils vs. algae. Will algae-derived biodiesel perform? Green Chem 13:3048–3065CrossRefGoogle Scholar
Knothe G (2014) A comprehensive evaluation of the cetane numbers of fatty acid methyl esters. Fuel 119:6–13CrossRefGoogle Scholar
Lam MK, Lee KT (2013) Catalytic transesterification of high viscosity crude microalgae lipid to biodiesel: effect of co-solvent. Fuel Process Technol 110:242–248CrossRefGoogle Scholar
Levine F, Kayea RV III, Wexler R, Sadvary DJ, Melick C, Scala JL (2014) Heat of combustion of fatty acids and fatty acid esters. J Am Oil Chem Soc 91:235–249CrossRefGoogle Scholar
Mandal S, Mallick N (2012) Biodiesel production by the green microalga Scenedesmus obliquus in a recirculatory aquaculture system. Appl Environ Microbiol 78:5929–5934CrossRefPubMedPubMedCentralGoogle Scholar
Nigam PS, Singh A (2011) Production of liquid biofuels from renewable resources. Prog Energy Combust Sci 37:52–68CrossRefGoogle Scholar
Pacini H, Silveira S, da Silva Filho AC (2013) The European Biofuels Policy: from where and where to? Eur Energy J 3:1–36Google Scholar
Qin JG (2010) Hydrocarbons from algae. In: Timmis KN (ed) Handbook of hydrocarbon and lipid microbiology. Springer, Berlin, pp 2817–2826CrossRefGoogle Scholar
Ramos MJ, Fernández CM, Casas A, Rodriguez L, Perez A (2009) Influence of fatty acid composition of raw materials on biodiesel properties. Bioresour Technol 100:261–268CrossRefPubMedGoogle Scholar
Ruina L, Zhong W, Peiyong N, Yang Z, Mingdi L, Lilin L (2014) Effects of cetane number improvers on the performance of diesel engine fuelled with methanol/biodiesel blend. Fuel 128:180–187CrossRefGoogle Scholar