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Primary Separation of Antioxidants (Unsaponifiables) the Wet Biomass Microalgae Chlamydomonas sp. and Production of the Biodiesel  [PDF]
Gisel Chenard Díaz, Yordanka Reyes Cruz, Mariana Monteiro Fortes, Carolina Vieira Viegas, René González Carliz, Nelson C. Furtado, Donato A. Gomes Aranda
Natural Science (NS) , 2014, DOI: 10.4236/ns.2014.615108
Abstract: This work studies the saponification which directs the wet biomass of algae Chlamydomonas sp. like a previous stage to production of biodiesel. This stage allows the obtainment of fatty acids to produce biodiesel, instead of the gross lipid fraction. In addition of the fatty acids, utilizing the same process one can also obtain the fraction unsaponifiable, these are soluble in apolar solvents and contain mainly carotenoids that can take action as antioxidants and photoprotectors, as they reduce the oxidation of unsaturated fatty acids. The saponification direct and extraction of fatty acids from biomass is faster and reduces the time and cost of operation. The separation of unsaponifiable matter from the biomass humid of microalgae Chlamydomonas sp., was held according to the method AOCS (Ca 6a-40), using extraction Liquid-liquid with hexane as solvent. Subsequently, phase hydroalcoholic or from soap, containing fatty acids, was acidified by addition of H2SO4 and the fatty acids were recovered by the addition of hexane. After acidulation of the soap, necessary for obtaining of the fatty acids was performed the stage of esterification for obtaining of biodiesel. The operating conditions were: molar ratio fatty acid:methanol (1:10), as catalyst 8% H2SO4 calculated in relation to the mass of fatty acid, 200 and reaction time of 90 minutes. The content of methyl esters was 96.8% determined by gas chromatography according to standard EN14103. The quality of biodiesel produced from wet biomass of Chlamydomonas sp. is according to the specification established by standard EN 14214 and RANP No. 14. For the identification of the composition the unsaponifiable fraction was used the method of High Performance Liquid Chromatography (HPLC). The composition of the material unsaponifiable found was of: Carotenoids total (0.76%); Lutein (0.45%); Zeaxanthin (0.07%); α-carotene (0.05%); β-carotene (0.11%); 13 cisβ-carotene (0.05%) and 9-cisβ-carotene (0.03%).
Optimization of Nitrogen, Phosphorus and Salt for Lipid Accumulation of Microalgae: Towards the Viability of Microalgae Biodiesel  [PDF]
Carolina T. Miranda, Daniel V. N. de Lima, Georgia C. Atella, Paula F. de Aguiar, Sandra M. F. O. Azevedo
Natural Science (NS) , 2016, DOI: 10.4236/ns.2016.812055
In recent years, microalgae biodiesel has attracted expressive attention and investment, once it was considered a potential resource for energy. Although the wide use of microalgae biodiesel is restricted by its high production cost. For cost-efficient and sustainable production of biodiesel from microalgae, a proper understanding of the variables and their impacts on physiology of the strains is required. In this study, a simple factorial design 23 was used to find optimal conditions for the cultivation of Ankistrodesmus sp. and Chlamydomonas sp. in batch culture. The three components considered were nitrate, phosphate and sodium chloride, used to assess the metabolic versatility of the strains in brackish conditions. The results showed that culture medium with 0.04 g·L?1 nitrate, 0.01 g·L?1 phosphate and 5.0 g·L?1 sodium chloride resulted to be the most effective condition to growth and fatty acids accumulation. Using this optimal condition, Ankistrodesmus sp. and Chlamydomonas sp. increased in 2.1 and 2.4 folds their fatty acids yield, respectively. Importantly, this protocol reduced 75% of the nitrate and phosphate concentrations of the original medium (ASM-1). Additionally, fatty acids analysis found that these strains were mainly constituted of C16-C18, in accordance with the requirements for biodiesel production. The simple factorial design applied here proved to be an important tool towards a better understanding of synergistic effects of tested factors on microalgae metabolism, and the resulting information could be used effectively to improve microalgae cultivation.
Current Status and Prospects of Biodiesel Production from Microalgae  [PDF]
Xiaodan Wu,Rongsheng Ruan,Zhenyi Du,Yuhuan Liu
Energies , 2012, DOI: 10.3390/en5082667
Abstract: Microalgae represent a sustainable energy source because of their high biomass productivity and ability to remove air and water born pollutants. This paper reviews the current status of production and conversion of microalgae, including the advantages of microalgae biodiesel, high density cultivation of microalgae, high-lipid content microalgae selection and metabolic control, and innovative harvesting and processing technologies. The key barriers to commercial production of microalgae biodiesel and future perspective of the technologies are also discussed.
Potency of Microalgae as Biodiesel Source in Indonesia  [cached]
H Hadiyanto,W Widayat,Andri Cahyo Kumoro
International Journal of Renewable Energy Development (IJRED) , 2012,
Abstract: Within 20 years, Indonesia should find another energy alternative to substitute current fossil oil. Current use of renewable energy is only 5% and need to be improved up to 17% of our energy mix program. Even though, most of the area in Indonesia is covered by sea, however the utilization of microalgae as biofuel production is still limited. The biodiesel from current sources (Jatropha, palm oil, and sorghum) is still not able to cover all the needs if the fossil oil cannot be explored anymore. In this paper, the potency of microalgae in Indonesia was analysed as the new potential of energy (biodiesel) sources.
Microalgae Lipid and Biodiesel Production: A Brazilian Challenge  [PDF]
Carolina T. Miranda, Roberta F. Pinto, Daniel V. N. de Lima, Carolina V. Viegas, Simone M. da Costa, Sandra M. F. O. Azevedo
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.615254
Abstract: Global increases in atmospheric CO2 and climate change are drawing considerable attention to identify sources of energy with lower environmental impact than those currently in use. Biodiesel production from microalgae lipids can, in the future, occupy a prominent place in energy generation because it represents a sustainable alternative to petroleum-based fuels. Several species of microalgae produce large amounts of lipids per biomass unit. Triacylglycerol is the fatty acid used for biodiesel production and the main source of energy reserves in microalgae. The current literature indicates that nutrient limitations can lead to triacylglycerol accumulation in different species of microalgae. Further efforts in microalgae screening for biodiesel production are needed to discover a native microalgae that will be feasible for biodiesel production in terms of biomass productivity and oil. This revision focuses in the biotechnological potential and viability of biodiesel production from microalgae. Brazil is located in a tropical region with high light rates and adequate average temperatures for the growth of microalgae. The wide availability of bodies of water and land will allow the country to produce renewable energy from microalgae.
Screening of Microalgae for Biodiesel Feedstock  [PDF]
Xi Chen, Guoqiang He, Zhiping Deng, Nan Wang, Wei Jiang, Sanfeng Chen
Advances in Microbiology (AiM) , 2014, DOI: 10.4236/aim.2014.47044

Three heterotrophic microalgae identified as Scenedesmus sp. Y5, Scenedesmus sp. Y7 and Chorellasp. Y9 were isolated and screened from natural water based on biomass yield and lipid productivity. Fatty acids’ composition analysis showed that both Y5 and Y7 mainly contained C16:0, C18:1 (n - 9), C18:2 (n - 6) and C18:3 (n - 3) and Y9 mainly contained C16:0, C18:0 and C18:2 (n - 6), suggesting that these microalgae can be ideal feedstock for biodiesel. Considering the specific growth rate and lipid productivity, the culture conditions were optimized for Scenedesmus sp. Y5, Scenedesmus sp. Y7 and Chorellasp. Y9. Based on the optimization of cultural conditions, all of these three microalgae were tested in fed-batch fermentation, and their biomass productivities were 4.960 g·L-1·d-1, 5.907 g·L-1·d-1 and 4.038 g·L-1

Nkongolo Mulumba,Ihab H. Farag
International Journal of Engineering Science and Technology , 2012,
Abstract: Biodiesel production from algae is a promising technique. Microalgae have the potential to produce 5,000-15,000 gallons of biodiesel/(acre-year). However, there are challenges; these include high yieldof algae biomass with high lipid content and the effective technique to harvest the grown algae, extract the algal oil and transesterify the oil to biodiesel. In this project Tubular PhotoBioReactor (TPBR) was designed and achieved a ten times increase in algae concentration. It produced 1g of dry algal biomass per liter of medium within 12 days, with a lipid content of 12% approximately. Healthy algal culture grew well in the TPBR reaching 56x106 cells/mL of culture medium. The 10 fold increase is higher than those reported for open ponds and helical photobioreactor.
Microalgae Isolation and Selection for Prospective Biodiesel?Production  [PDF]
Van Thang Duong,Yan Li,Ekaterina Nowak,Peer M. Schenk
Energies , 2012, DOI: 10.3390/en5061835
Abstract: Biodiesel production from microalgae is being widely developed at different scales as a potential source of renewable energy with both economic and environmental benefits. Although many microalgae species have been identified and isolated for lipid production, there is currently no consensus as to which species provide the highest productivity. Different species are expected to function best at different aquatic, geographical and climatic conditions. In addition, other value-added products are now being considered for commercial production which necessitates the selection of the most capable algae strains suitable for multiple-product algae biorefineries. Here we present and review practical issues of several simple and robust methods for microalgae isolation and selection for traits that maybe most relevant for commercial biodiesel production. A combination of conventional and modern techniques is likely to be the most efficient route from isolation to large-scale cultivation.
High Lipid Induction in Microalgae for Biodiesel Production  [PDF]
Kalpesh K. Sharma,Holger Schuhmann,Peer M. Schenk
Energies , 2012, DOI: 10.3390/en5051532
Abstract: Oil-accumulating microalgae have the potential to enable large-scale biodiesel production without competing for arable land or biodiverse natural landscapes. High lipid productivity of dominant, fast-growing algae is a major prerequisite for commercial production of microalgal oil-derived biodiesel. However, under optimal growth conditions, large amounts of algal biomass are produced, but with relatively low lipid contents, while species with high lipid contents are typically slow growing. Major advances in this area can be made through the induction of lipid biosynthesis, e.g., by environmental stresses. Lipids, in the form of triacylglycerides typically provide a storage function in the cell that enables microalgae to endure adverse environmental conditions. Essentially algal biomass and triacylglycerides compete for photosynthetic assimilate and a reprogramming of physiological pathways is required to stimulate lipid biosynthesis. There has been a wide range of studies carried out to identify and develop efficient lipid induction techniques in microalgae such as nutrients stress (e.g., nitrogen and/or phosphorus starvation), osmotic stress, radiation, pH, temperature, heavy metals and other chemicals. In addition, several genetic strategies for increased triacylglycerides production and inducibility are currently being developed. In this review, we discuss the potential of lipid induction techniques in microalgae and also their application at commercial scale for the production of biodiesel.
Current Status and Outlook in the Application of Microalgae in Biodiesel Production and Environmental Protection  [PDF]
Junfeng Rong,Hui Chen,Qiang Wang
Frontiers in Energy Research , 2014, DOI: 10.3389/fenrg.2014.00032
Abstract: Microalgae have been currently recognized as a group of the most potential feedstocks for biodiesel production due to high productivity potential, efficient biosynthesis of lipids, and less competition with food production. Moreover, utilization of microalgae with environmental purposes (CO2 fixation, NOx, and wastewater treatment) and biorefinery has been reported. However, there are still challenges that need to be addressed to ensure stable large-scale production with positive net energy balance. This review gives an overview of the current status of the application of microalgae in biodiesel production and environmental protection. The practical problems not only facing the microalgae biodiesel production but also associated with microalgae application for environmental pollution control, in particular biological fixation of greenhouse gas (CO2 and NOx) and wastewater treatment are described in detail. Notably, the synergistic combination of various applications (e.g., food, medicine, wastewater treatment, and flue gas treatment) with biodiesel production could enhance the sustainability and economics of the algal biodiesel production system.
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