共查询到20条相似文献,搜索用时 0 毫秒
1.
Oil extraction from microalgae for biodiesel production 总被引:3,自引:0,他引:3
Ronald Halim Brendan GladmanMichael K. Danquah Paul A. Webley 《Bioresource technology》2011,102(1):178-185
This study examines the performance of supercritical carbon dioxide (SCCO2) extraction and hexane extraction of lipids from marine Chlorococcum sp. for lab-scale biodiesel production. Even though the strain of Chlorococcum sp. used in this study had a low maximum lipid yield (7.1 wt% to dry biomass), the extracted lipid displayed a suitable fatty acid profile for biodiesel [C18:1 (∼63 wt%), C16:0 (∼19 wt%), C18:2 (∼4 wt%), C16:1 (∼4 wt%), and C18:0 (∼3 wt%)]. For SCCO2 extraction, decreasing temperature and increasing pressure resulted in increased lipid yields. The mass transfer coefficient (k) for lipid extraction under supercritical conditions was found to increase with fluid dielectric constant as well as fluid density. For hexane extraction, continuous operation with a Soxhlet apparatus and inclusion of isopropanol as a co-solvent enhanced lipid yields. Hexane extraction from either dried microalgal powder or wet microalgal paste obtained comparable lipid yields. 相似文献
2.
High cell density cultivation of microalgae via heterotrophic growth mechanism could effectively address the issues of low productivity and operational constraints presently affecting the solar driven biodiesel production. This paper reviews the progress made so far in the development of commercial-scale heterotrophic microalgae cultivation processes. The review also discusses on patentable concepts and innovations disclosed in the past four years with regards to new approaches to microalgal cultivation technique, improvisation on the process flow designs to economically produced biodiesel and genetic manipulation to confer desirable traits leading to much valued high lipid-bearing microalgae strains. 相似文献
3.
《Critical reviews in biotechnology》2013,33(3):293-308
In recent years, the not too distant exhaustion of fossil fuels is becoming apparent. Apart from this, the combustion of fossil fuels leads to environmental concerns, the emission of greenhouse gases and issues with global warming and health problems. Production of biodiesel from microalgae may represent an attractive solution to the above mentioned problems, and can offer a renewable source of fuel with fewer pollutants. This review presents a compilation of engineering challenges related to microalgae as a source of biodiesel. Advantages and current limitations for biodiesel production are discussed; some aspects of algae cells biology, with emphasis on cell wall composition, as it represents a barrier for fatty acid extraction and lipid droplets are also presented. In addition, recent advances in the different stages of the manufacturing process are included, starting from the strain selection and finishing in the processing of fatty acids into biodiesel. 相似文献
4.
Gour Gopal Satpati Sanjaya Kumar Mallick Ruma Pal 《Biotechnology and Bioprocess Engineering》2015,20(6):1044-1055
A simple and high-throughput method for determining in situ intracellular neutral lipid accumulation in Chlorella ellipsoidea and Chlorococcum infusionum with flow cytometry and confocal microscopy was established by employing different solvents and a lipophilic dye, Nile red. Seven different organic solvents, acetic acid, dimethyl sulfoxide (DMSO), acetone, methanol, ethanol, n-hexane, and chloroform at different concentrations ranging from 0 to 80% (v/v) were tested. The fluorescence signal for neutral lipids was collected with a 586/42 emission filter (PE-A) and the maximum fluorescence intensity (% grandparent) was measured as 74.01 ± 4.82% for Chlorella and 70.1 ± 5.52% for Chlorococcum at 30% acetic acid (v/v). The statistical analysis of Nile red-stained cells showed a high coefficient of variation (CV), standard deviation (SD), mean, and median values in the acetic acid-based staining method, followed by DMSO, n-hexane and chloroform. Confocal microscopy revealed a high rate of accumulation of cytosolic neutral lipids when stained with Nile red and other organic solvents. Higher lipid accumulation in Fesupplemented conditions was also detected and a maximum lipid content of 57.36 ± 0.41% (4-fold) in Chlorella and 48.20 ± 0.43% (4-fold) in Chlorococcum were measured at 0.001 g/L of ferrous sulfate (FeSO4). High fluorescence intensity (75.16 ± 0.24% in Chlorella and 72.24 ± 1.07% in Chlorococcum) in Fe-treated cells confirmed the efficiency of the staining procedure. 相似文献
5.
6.
Haiying Tang Meng Chen M.E.D. Garcia Nadia Abunasser K.Y. Simon Ng Steven O. Salley 《Biotechnology and bioengineering》2011,108(10):2280-2287
Microalgae are among the most promising of non‐food based biomass fuel feedstock alternatives. Algal biofuels production is challenged by limited oil content, growth rate, and economical cultivation. To develop the optimum cultivation conditions for increasing biofuels feedstock production, the effect of light source, light intensity, photoperiod, and nitrogen starvation on the growth rate, cell density, and lipid content of Chlorella minutissima were studied. The fatty acid content and composition of Chlorella minutissima were also investigated under the above conditions. Fluorescent lights were more effective than red or white light‐emitting diodes for algal growth. Increasing light intensity resulted in more rapid algal growth, while increasing the period of light also significantly increased biomass productivity. Our results showed that the lipid and triacylglycerol content were increased under N starvation conditions. Thus, a two‐phase strategy with an initial nutrient‐sufficient reactor followed by a nutrient deprivation strategy could likely balance the desire for rapid and high biomass generation (124 mg/L) with a high oil content (50%) of Chlorella minutissima to maximize the total amount of oil produced for biodiesel production. Moreover, methyl palmitate (C16:0), methyl oleate (C18:1), methyl linoleate (C18:2), and methyl linolenate (C18:3) are the major components of Chlorella minutissima derived FAME, and choice of light source, intensity, and N starvation impacted the FAME composition of Chlorella minutissima. The optimized cultivation conditions resulted in higher growth rate, cell density, and oil content, making Chlorella minutissima a potentially suitable organism for biodiesel feedstock production. Biotechnol. Bioeng. 2011;108: 2280–2287. © 2011 Wiley Periodicals, Inc. 相似文献
7.
Seok-Joo Lee Sugeun Go Gwi-Taek Jeong Sung-Koo Kim 《Biotechnology and Bioprocess Engineering》2011,16(3):561-566
Marine microalgae were studied as potential resources for the production of biodiesel. Five marine microalgae, Tetraselmis suecica, Phaeodactylum tricornutum, Chaetoceros calcitrans, Isochrysis galbana, and Nannochloropsis oculata were cultured in f/2 media, 12:12 L:D cycle at 20 ± 1°C with a light intensity of 36.3 μmol/m2/sec using a 15-L circular cylindrical photobioreactor. The dry cell weight, specific growth rate, biomass productivity, oil
content and fatty acid composition of palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid of microalgae
were determined. T. suecica, I. galbana, and N. oculata showed high dry cell weights of 0.58, 0.57, and 0.57 g/L, respectively. The culture period of T. suecica to reach the stationary phase was 9 days. On the other hand, N. oculata showed the longest culture period of 28 days to reach the stationary phase. T. suecica absorbed nitrate at the initial stages of cell growth, decreasing the nitrate concentration to 0.5 mg/L on day-7 of the culture.
The highest oil contents were observed in P. tricornutum with a 25.31% dry cell weight and I. galbana with a 23.15% dry cell weight on day-9 after the stationary phase. I. galbana showed 417.33 mg of palmitic acid per g oil and T. suecica showed 235.61 mg of oleic acid per g oil. Stearic acid, linoleic acid, and linolenic acid did not exceed 30.02 mg/g oil in
any of the microalgae. T. suecica showed the shortest culture period of 9 days to reach the stationary phase. Therefore, the highest biomass production of
0.58 g/L was obtained and I. galbana showed high biomass production of 0.57 g/ L and oil content of 23.15% of dry cell weight. Therefore, T. suecica and I. galbana can be selected as a potential candidate for the production of biodiesel. 相似文献
8.
Y. M. Dyo S. E. Vonlanthen S. Purton B. K. Zayadan 《Russian Journal of Plant Physiology》2013,60(4):549-554
New microalgal strains that are native to South-East Kazakhstan were isolated and characterized with a view to identifying suitable candidates for biodiesel production. Six strains of chlorophyte algae (named K1–K6) were recovered from environmental samples as axenic cultures, and molecular analysis revealed that five (K1–K5) are strains of Parachlorella kessleri, whereas K6 is a strain of Chlorella vulgaris. A third isolate from Uzbekistan (termed UZ) was also identified as a separate strain of P. kessleri. All strains show high growth rates and an ability to utilize acetate as an exogenous source of fixed carbon. Furthermore, under conditions of nitrogen depletion, all three strains showed a significant accumulation of neutral lipids (triacylglycerides). P. kessleri K5 and C. vulgaris K6 therefore represent promising autochthon strains for large-scale cultivation and biodiesel production in Kazakhstan. 相似文献
9.
Del Campo JA Moreno J Rodríguez H Vargas MA Rivas J Guerrero MG 《Journal of biotechnology》2000,76(1):51-59
Fifteen strains of chlorophycean microalgae have been investigated with regard to their carotenoid profile. Lutein, beta-carotene and violaxanthin were present in virtually all of the strains, lutein, in general, being the most abundant carotenoid, whereas canthaxanthin and astaxanthin were found in some strains only. Chlorella fusca SAG 211-8b, Chlorococcum citriforme SAG 62.80, Muriellopsis sp., Neospongiococcum gelatinosum SAG B 64.80 and Chlorella zofingiensis CCAP 211/14 exhibited high lutein levels, the latter strain containing in addition substantial amounts of astaxanthin. Muriellopsis sp. was further characterized, since besides a high lutein content (up to 35 mg l(-1) culture), it had the highest growth rate (up to 0.17-0.23 h(-1)) and maximal standing cell density (up to 8 x 10(10) cells l(-1) culture). These levels of lutein are in the range of those reported for astaxanthin in Haematococcus and for beta-carotene in Dunaliella, microalgae of recognized interest for the production of these carotenoids. Lutein content of Muriellopsis sp. increased during the exponential phase of growth, with the highest value being recorded in the early stationary phase. Maximum levels of lutein in Muriellopsis sp. cultures were recorded at 20-40 mM NaNO3, 2-100 mM NaCl, 460 micromol photon m(-2) s(-1), pH 6.5 and 28 degrees C, conditions which were, in general, also optimal for cell growth. Growth-limiting conditions, such as pH values of 6 or 9 and a temperature of 33 degrees C, were found to stimulate carotenogenesis in Muriellopsis sp. This strain represents a potential source of lutein, a commercially interesting carotenoid of application in aquaculture and poultry farming, as well as in the prevention of cancer and diseases related to retinal degeneration. 相似文献
10.
Laura Azócar Gustavo Ciudad Hermann J. Heipieper Rodrigo Navia 《Applied microbiology and biotechnology》2010,88(3):621-636
As biodiesel (fatty acid methyl ester (FAME)) is mainly produced from edible vegetable oils, crop soils are used for its production,
increasing deforestation and producing a fuel more expensive than diesel. The use of waste lipids such as waste frying oils,
waste fats, and soapstock has been proposed as low-cost alternative feedstocks. Non-edible oils such as jatropha, pongamia,
and rubber seed oil are also economically attractive. In addition, microalgae, bacteria, yeast, and fungi with 20% or higher
lipid content are oleaginous microorganisms known as single cell oil and have been proposed as feedstocks for FAME production.
Alternative feedstocks are characterized by their elevated acid value due to the high level of free fatty acid (FFA) content,
causing undesirable saponification reactions when an alkaline catalyst is used in the transesterification reaction. The production
of soap consumes the conventional catalyst, diminishing FAME production yield and simultaneously preventing the effective
separation of the produced FAME from the glycerin phase. These problems could be solved using biological catalysts, such as
lipases or whole-cell catalysts, avoiding soap production as the FFAs are esterified to FAME. In addition, by-product glycerol
can be easily recovered, and the purification of FAME is simplified using biological catalysts. 相似文献
11.
Gnouma Asma Sehli Emna Medhioub Walid Ben Dhieb Rym Masri Mahmoud Mehlmer Norbert Slimani Wissem Sebai Khaled Zouari Amel Brück Thomas Medhioub Amel 《Bioprocess and biosystems engineering》2018,41(10):1449-1459
Bioprocess and Biosystems Engineering - Microalgae could be of importance for future biodiesel production as an alternative for a third generation of biofuels. To select the most appropriate strain... 相似文献
12.
The rapid increase of CO(2) concentration in the atmosphere combined with depleted supplies of fossil fuels has led to an increased commercial interest in renewable fuels. Due to their high biomass productivity, rapid lipid accumulation, and ability to survive in saline water, microalgae have been identified as promising feedstocks for industrial-scale production of carbon-neutral biodiesel. This study examines the principles involved in lipid extraction from microalgal cells, a crucial downstream processing step in the production of microalgal biodiesel. We analyze the different technological options currently available for laboratory-scale microalgal lipid extraction, with a primary focus on the prospect of organic solvent and supercritical fluid extraction. The study also provides an assessment of recent breakthroughs in this rapidly developing field and reports on the suitability of microalgal lipid compositions for biodiesel conversion. 相似文献
13.
Jungmin Kim Gursong Yoo Hansol Lee Juntaek Lim Kyochan Kim Chul Woong Kim Min S. Park Ji-Won Yang 《Biotechnology advances》2013
Despite receiving increasing attention during the last few decades, the production of microalgal biofuels is not yet sufficiently cost-effective to compete with that of petroleum-based conventional fuels. Among the steps required for the production of microalgal biofuels, the harvest of the microalgal biomass and the extraction of lipids from microalgae are two of the most expensive. In this review article, we surveyed a substantial amount of previous work in microalgal harvesting and lipid extraction to highlight recent progress in these areas. We also discuss new developments in the biodiesel conversion technology due to the importance of the connectivity of this step with the lipid extraction process. Furthermore, we propose possible future directions for technological or process improvements that will directly affect the final production costs of microalgal biomass-based biofuels. 相似文献
14.
This paper analyses the potential environmental impacts and economic viability of producing biodiesel from microalgae grown in ponds. A comparative Life Cycle Assessment (LCA) study of a notional production system designed for Australian conditions was conducted to compare biodiesel production from algae (with three different scenarios for carbon dioxide supplementation and two different production rates) with canola and ULS (ultra-low sulfur) diesel. Comparisons of GHG (greenhouse gas) emissions (g CO2-e/t km) and costs (¢/t km) are given. Algae GHG emissions (−27.6 to 18.2) compare very favourably with canola (35.9) and ULS diesel (81.2). Costs are not so favourable, with algae ranging from 2.2 to 4.8, compared with canola (4.2) and ULS diesel (3.8). This highlights the need for a high production rate to make algal biodiesel economically attractive. 相似文献
15.
16.
Panjaphol Chaisutyakorn Jantana Praiboon Chatcharee Kaewsuralikhit 《Journal of applied phycology》2018,30(1):37-45
Cultivation temperature is one of the major factors affecting the growth and lipid accumulation of microalgae. In this study, the effects of temperature on the growth, lipid content, fatty acid composition and biodiesel properties of the marine microalgae Chaetoceros sp. FIKU035, Tetraselmis suecica FIKU032 and Nannochloropsis sp. FIKU036 were investigated. These species were cultured at different temperatures (25, 30, 35 and 40 °C). The results showed that the specific growth rate, biomass and lipid content of all microalgae decreased with increasing temperature. With regards to fatty acids, the presence of saturated fatty acids (SFAs) in T. suecica FIKU032 and Nannochloropsis sp. FIKU036 decreased with increasing temperature, in contrast with polyunsaturated fatty acids (PUFAs). Moreover, Chaetoceros sp. FIKU035 was the only species that could grow at 40 °C. The highest lipid productivity was observed in Chaetoceros sp. FIKU035 when cultivated at 25 °C (66.73 ± 1.34 mg L?1 day?1) and 30 °C (61.35 ± 2.89 mg L?1 day?1). Moreover, the biodiesel properties (cetane number, cold filter plugging point, kinematic viscosity and density) of the lipids obtained from this species were in accordance with biodiesel standards. This study indicated that Chaetoceros sp. FIKU035 can be considered as a suitable species for biodiesel production in outdoor cultivation. 相似文献
17.
Systematic investigation of biomass and lipid productivity by microalgae in photobioreactors for biodiesel application 总被引:4,自引:0,他引:4
J. Pruvost G. Van VoorenB. Le Gouic A. Couzinet-MossionJ. Legrand 《Bioresource technology》2011,102(1):150-158
We describe a methodology to investigate the potential of given microalgae species for biodiesel production by characterizing their productivity in terms of both biomass and lipids. A multi-step approach was used: determination of biological needs for macronutrients (nitrate, phosphate and sulphate), determination of maximum biomass productivity (the “light-limited” regime), scaling-up of biomass production in photobioreactors, including a theoretical framework to predict corresponding productivities, and investigation of how nitrate starvation protocol affects cell biochemical composition and triggers triacylglycerol (TAG) accumulation. The methodology was applied to two freshwater strains, Chlorella vulgaris and Neochloris oleoabundans, and one seawater diatom strain, Cylindrotheca closterium. The highest total lipid content was achieved with N. oleoabundans (25-37% of DW), while the highest TAG content was found in C. vulgaris (11-14% of DW). These two species showed similar TAG productivities. 相似文献
18.
Eduardo Henrique Bredda Aneirson Francisco Da Silva Messias Borges Silva 《Preparative biochemistry & biotechnology》2020,50(4):379-389
AbstractFor a feasible microalgae biodiesel, increasing lipid productivity is a key parameter. An important cultivation parameter is light wavelength (λ). It can affect microalgal growth, lipid yield, and fatty acid composition. In the current study, the mixture design was used as an alternative to model the influence of the λ on the Dunaliella salina lipid productivity. The illumination was considered to be the mixture of different λ (the light colors blue, red, and green). All experiments were performed with and without sodium acetate (4?g/L), as carbon source, allowing the identification of the impact of the cultivation regimen (autotrophic or mixotrophic). Without sodium acetate, the highest lipid productivity was obtained using blue and red light. The use of mixotrophic cultivations significantly enhanced the results. The optimum obtained result was mixotrophic cultivation under 65% blue and 35% green light, resulting in biomass productivity of 105.06 mgL?1day?1, a lipid productivity of 53.47 mgL?1day?1, and lipid content of 50.89%. The main fatty acids of the oil obtained in this cultivation were oleic acid (36.52%) and palmitic acid (18.31%). 相似文献
19.
微藻生物柴油研发态势分析 总被引:3,自引:0,他引:3
微藻是光合效率最高的原始植物之一,与农作物相比,单位面积的产率可高出数十倍。微藻生物柴油技术首先包括微藻的筛选和培育,获得性状优良的高含油量藻种,然后在光生物反应器中吸收阳光、CO2等,生成微藻生物质,最后经过采收、加工,转化为微藻生物柴油。完整的微藻生物柴油成套技术链涵盖多个技术环节,是一个复杂的系统工程,包括微藻生物工程技术、微藻高效规模化养殖技术,以及微藻生物质采收、加工与转化技术等。其中,降低生产成本是当前微藻生物柴油研究面临的主要挑战,各国的研究机构为此开展了多方面的研究。 相似文献
20.
Due to negative environmental influence and limited availability, petroleum-derived fuels need to be replaced by renewable
biofuels. Biodiesel has attracted intensive attention as an important biofuel. Microalgae have numerous advantages for biodiesel
production over many terrestrial plants. There are a series of consecutive processes for biodiesel production with microalgae
as feedstock, including selection of adequate microalgal strains, mass culture, cell harvesting, oil extraction and transesterification.
To reduce the overall production cost, technology development and process optimization are necessary. Genetic engineering
also plays an important role in manipulating lipid biosynthesis in microalgae. Many approaches, such as sequestering carbon
dioxide from industrial plants for the carbon source, using wastewater for the nutrient supply, and maximizing the values
of by-products, have shown a potential for cost reduction. This review provides a brief overview of the process of biodiesel
production with microalgae as feedstock. The methods associated with this process (e.g. lipid determination, mass culture,
oil extraction) are also compared and discussed. 相似文献