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Hydroesterification of Nannochloropsis oculata microalga’s biomass to biodiesel on Al2O3 supported Nb2O5 catalyst  [PDF]
Angel Almarales, Gisel Chenard, Roberto Abdala, Donato A. Gomes, Yordanka Reyes, Neyda Om Tapanes
Natural Science (NS) , 2012, DOI: 10.4236/ns.2012.44031
Abstract: Hydroesterification process has been presented biodiesel production from oil the green microalga Nannochloropsis oculata raw materials. Biodiesel studied in this work is the main product got from the hydroesterification of biomass the Nannochloropsis oculata and was obtained from esterification of fatty acid (product of a hydrolysis reaction) with methanol. It was used as catalyst the niobic acid pure and supported on δ-aluminum. The product was evaluated by gas chromatography and other analyses. The optimum conditions found in the conversion (%) for the hydrolysis reactions of the biomass (92.3%). Better results were observed in the algae concentration 20%, lead at 300?C with 20% of catalyst. For esterification of fatty acids of Nannochloropsis oculata (92.24%), were observed the molar ratio methanol: fat acid 3, lead at 200°C with 20% of catalyst supported.
Study of Soybean Oil Hydrolysis Catalyzed by Thermomyces lanuginosus Lipase and Its Application to Biodiesel Production via Hydroesterification
Elisa d'Avila Cavalcanti-Oliveira,Priscila Rufino da Silva,Alessandra Pe anha Ramos,Donato Alexandre Gomes Aranda,Denise Maria Guimar es Freire
Enzyme Research , 2011, DOI: 10.4061/2011/618692
Abstract: The process of biodiesel production by the hydroesterification route that is proposed here involves a first step consisting of triacylglyceride hydrolysis catalyzed by lipase from Thermomyces lanuginosus (TL 100L) to generate free fatty acids (FFAs). This step is followed by esterification of the FFAs with alcohol, catalyzed by niobic acid in pellets or without a catalyst. The best result for the enzyme-catalyzed hydrolysis was obtained under reaction conditions of 50% (v/v) soybean oil and 2.3% (v/v) lipase (25 U/mL of reaction medium) in distilled water and at 60°C; an 89% conversion rate to FFAs was obtained after 48 hours of reaction. For the esterification reaction, the best result was with an FFA/methanol molar ratio of 1:3, niobic acid catalyst at a concentration of 20% (w/w FFA), and 200°C, which yielded 92% conversion of FFAs to soy methyl esters after 1 hour of reaction. This study is exceptional because both the hydrolysis and the esterification use a simple reaction medium with high substrate concentrations.
Biodiesel production from microalgal isolates of southern Pakistan and quantification of FAMEs by GC-MS/MS analysis
Syed Musharraf, Muhammad Ahmed, Noureen Zehra, Nurul Kabir, M Choudhary, Atta-ur Rahman
Chemistry Central Journal , 2012, DOI: 10.1186/1752-153x-6-149
Abstract: Growth rate, biomass productivity and oil content of each algal species have been investigated under autotrophic condition. Biodiesel was produced from algal oil by acid catalyzed transesterification reaction and resulting fatty acid methyl esters (FAMEs) content was analyzed by GC/MS. Fatty acid profiling of the biodiesel, obtained from various microalgal oils showed high content of C-16:0, C-18:0, cis-Δ9C-18:1, cis-Δ11C-18:1 (except Scenedesmus quadricauda) and 10-hydroxyoctadecanoic (except Scenedesmus acuminatus). Absolute amount of C-14:0, C-16:0 and C-18:0 by a validated GC-MS/MS method were found to be 1.5-1.7, 15.0-42.5 and 4.2-18.4 mg/g, respectively, in biodiesel obtained from various microalgal oils. Biodiesel was also characterized in terms of cetane number, kinematic viscosity, density and higher heating value and compared with the standard values.Six microalgae of local origin were screened for biodiesel production. A method for absolute quantification of three important saturated fatty acid methyl esters (C-14, C-16 and C-18) by gas chromatography-tandem mass spectrometry (GC-MS/MS), using multiple reactions monitoring (MRM) mode, was employed for the identification and quantification of biodiesels obtained from various microalgal oils. The results suggested that locally found microalgae can be sustainably harvested for the production of biodiesel. This offers the tremendous economic opportunity for an energy-deficient nation.Fossil fuel is now widely recognized as unsustainable resource with depleting supplies and increasing cost. Moreover, accumulation of carbon dioxide due to fossil fuels in the environment is getting higher. Therefore, renewable fuels are necessary for environmental and economic sustainability [1-3].Biodiesel, as an alternative fuel, has attracted major interest worldwide in recent years. Conventional sources of biodiesel include plant oils and animal fats. The energy content, cetane number and viscosity of biodiesel are similar t
Advancement in the Utilization of Biomass-Derived Heterogeneous Catalysts in Biodiesel Production  [PDF]
Nurudeen Ishola Mohammed, Nassereldeen Ahmed Kabbashi, Abass Olanrewaju Alade, Sarina Sulaiman
Green and Sustainable Chemistry (GSC) , 2018, DOI: 10.4236/gsc.2018.81006
Abstract: Solid oxide catalysts derived from various renewable sources have produced significant yield of methyl esters of enhanced purity. These materials are sourced for due to their advantages ranging from low cost, recoverability and reusability, environmental benign-ness, thermal stability and high quality product generation. For a possible greener production process, many researchers in literature reported the use of biomass-derived heterogeneous catalyst in biodiesel synthesis producing high quality pure product. The catalysts were majorly modified through simple physical cost effective and energy saving operations. This paper explores some of these bio-based heterogeneous catalyst used in biodiesel production via transesterification and esterification approach and their performance in FAME yield and conversion. The feedstock consideration which warrant the route selection, various approaches that are adopted in biodiesel production, performance of renewable heterogeneous catalyst and the measures that were adopted to enhance efficiency of the catalyst were considerably highlighted. It is observed that the prospects of organic-based solid catalyst in biodiesel development is a promising enterprise compared to the conventional methods utilizing homogeneous chemical catalyst, which generates wastewater requiring treatment before disposal and generates product that may cause engine malfunction. This review work aimed at providing detailed and up-to-date record of the trend in renewable catalyst development in biodiesel synthesis. This is expected to inform a suitable selection and reaction conditions in the development of biodiesel from the very many feed stocks.
Influence of initial pH on hydrogen production from lipid-extracted microalgal biomass residues

Yang Zhiman,Xu Xiaohui,Meng Xianwu,Fan Xiaolei,Li Xiaoping,Guo Rongbo,

环境工程学报 , 2011,
Abstract: It is significant for development of microalgal biodiesel industry to utilize lipid-extracted microalgal biomass residues. Hydrogen production from lipid-extracted microalgal biomass residues was performed via batch tests by using heat treated anaerobic digested sludge, and the effect of initial pH 5~9 on the biohydrogen production was firstly investigated. The results showed that increasing the initial pH led to decreases in hydrogen yield and cumulative hydrogen production. The hydrogen production rate increased with initial pH from 5 to 6.5, and then decreased as the pH further increased to 9. The lowest initial pH 5 offered the highest hydrogen yield of 50 mL H2/g VS (volatile solid), a lower hydrogen production rate of 2.69 mL H2/h, and a longer lag-phase of 20 h, whereas the highest hydrogen production rate of 3.79 mL H2/h and a lower lag-phase time of 1.7 h occurred at optimal initial pH 6.5.
KF/CaO as solid base catalyst for transesterification to biodiesel by ultrasound

燃料化学学报 , 2010,
Abstract: Biodiesel fuel,chemically consisted of fatty acid methylester(FAME) produced by methanolysis of natural triglycerides such as animal fats and vegetable oils,is a kind of biomass energy.KF/CaO was used as solid base catalyst for transesterification to produce biodiesel fuel with ultrasound as an auxiliary means.Compared with mechanical stirring,ultrasound treatment is an effective method to increase the yield of biodiesel and shorten the reaction time.By single factor method,the optimization of reaction cond...
Exploitation of Oil-bearing Microalgae for Biodiesel

Donghui Song,Lijun Hou,Dingji Shi,

生物工程学报 , 2008,
Abstract: As a renewable energy sources to replace conventional fossil fuels, biodiesel fuels have been becoming increasingly requirements to global fuels market. Biodiesel derived from oil crops cannot realistically satisfy even more fraction of the raw material existing costs and soil competitive demand for its growth. Microalgae appear to be the advantage of costs that is capable of higher photosynthetic efficiency, larger biomass, faster growth compared to those of oil crops. Lipid content of many microalgae is usually 80% of its dry weight. Genetic microalgae with high-oil productivity by genetic manipulations are capable of making microalgal biodiesel economically competitive with petrodiesel through large-scale production of genetic microalgal biomass. As demonstrated here, the use of biodiesel fuels in home and abroad are currently introduced, and the cost advantage of microalgae as the raw material is analyzed; And moreover, the progress of microalgal genetic engineering in regulation of lipid metabolism and the problems in the construct of genetic microalgae strains as well as approaches for making microalgal biodiesel appear to be an important source of renewable fuel that has the potential to completely displace fossil diesel are discussed in this review.
Production of Biodiesel Using Ethanol Way and Alkaline Catalyst
Cesar Aparecido da Silva
Engenharia Ambiental : Pesquisa e Tecnologia , 2010,
Abstract: The potential inputs to promote the supply of the demand for power generation has become the aim of several scientific researches to mitigate environmental impacts. The biodiesel is the highlight solution that can be obtained through the transesterification process. The aim this present work was the biodiesel production using ethanol and crude oil sunflower as inputs and potassium ethoxide such as catalyst for the rection. Were produced seven samples using different parameters. The product with high rate of ethyl ester was the one with catalyst and reaction time optimized. However, it has showed the presence of glycerol, suggesting the use of other unit operations such as cooling and centrifugation to improve the purity of the biodiesel formed is necessary. The parameters used in this experiment (oil, catalyst and water washing contents, reaction time, temperature and agitation speed) showed critical endpoints to be monitored during the production of biodiesel due interfering the quality and yield to the final product. In addition, the inappropriate speed of agitation in the reactor for ethanol way in the presence of an alkaline catalyst can gelatinize the mixture of reactants due the emulsion formed.
Sodium phosphate as a solid catalyst for biodiesel preparation
Jiang, S. T.;Zhang, F. J.;Pan, L. J.;
Brazilian Journal of Chemical Engineering , 2010, DOI: 10.1590/S0104-66322010000100012
Abstract: sodium phosphate (na3po4) was chosen as catalyst for biodiesel preparation from rapeseed oil. the effects of mass ratio of catalyst to oil, molar ratio of methanol to oil, reaction temperature and rotation speed on biodiesel yield were investigated. for a mass ratio of catalyst to oil of 3%, molar ratio of methanol to oil of 9:1, reaction temperature of 343k and rotation speed of 600rpm, the transesterification was nearly completed within 20 minutes. na3po4 has a similar activity to homogeneous catalysts. na3po4 could be used repeatedly for 8 runs without any activation treatment and no obvious activity loss was observed. the concentrations of catalyst in biodiesel ranged from 0.6 to 0.7 mg/g. compared to na3po4, na3po4.10h2o was cheaper, but the final yield was 71.3%, much lower than that of na3po4 at 99.7%.
Assessment of Environmental Stresses for Enhanced Microalgal Biofuel Production – An Overview  [PDF]
Dan Cheng,Qingfang He
Frontiers in Energy Research , 2014, DOI: 10.3389/fenrg.2014.00026
Abstract: Microalgal biofuels are currently considered to be the most promising alternative to future renewable energy source. Microalgae have great potential to produce various biofuels, including biodiesel, bioethanol, biomethane, and biohydrogen. Cultivation of biofuel-producing microalgae demands favorable environmental conditions, such as suitable light, temperature, nutrients, salinity, and pH. However, these conditions are not always compatible with the conditions beneficial to biofuel production, because biofuel-related compounds (such as lipids and carbohydrates) tend to accumulate under environmental-stress conditions of light, temperature, nutrient, and salt. This paper presents a brief overview of the effects of environmental conditions on production of microalgal biomass and biofuel, with specific emphasis on how to utilize environmental stresses to improve biofuel productivity. The potential avenues of reaping the benefits of enhanced biofuel production by environmental stresses while maintaining high yields of biomass production have been discussed.
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