Potential Biodiesel Feedstock Research Articles

Experimental study on performance and exhaust emissions of a diesel engine fuelled with Ceiba pentandra biodiesel blends

Nowadays, production of biodiesel from non-edible feedstock is gaining more attention than edible oil to replace diesel fuel. Thus, Ceiba pentandra is chosen as a potential biodiesel feedstock for the present investigations based on the availability in Indonesia and Malaysia. C. pentandra methyl ester was prepared by two-step acid esterification (H2SO4) and base transesterification (NaOH) process. The purpose of this study is to examine the engine performance and emission characteristic of C. pentandra biodiesel diesel blends in internal combustion. Besides, the detailed properties of C. pentandra biodiesel, biodiesel diesel blends and diesel were measured and evaluated. After that, the biodiesel diesel blends (10%, 20%, 30% and 50%) were used to conduct engine performance and exhaust emission characteristic at different engine speeds. The experimental results showed that CPB10 blend give the best results on engine performance such as engine torque and power at 1900rpm with full throttle condition. Besides, the brake specific fuel consumption at maximum torque (161g/kWh) for CPB10 is higher about 22.98% relative to diesel fuel (198g/kWh). This is shown that the lower biodiesel diesel blends ratio will increase the performance and reduce the fuel consumption. Moreover, the exhaust emissions showed that CO, HC and smoke opacity were reduced for all biodiesel diesel blends. However, NOx and CO2 were increased compared to petrol diesel. Overall, the results proved that C. pentandra biodiesel is a suitable alternative and substitute fuel to diesel.

Evaluation of potential biodiesel feedstock production from oleaginous insect Solenopsis sp.

Oil production from single cells has been in development since the 1980s primarily for the pharmaceutical and neutraceutical industries, but the technology for using microorganisms to convert plant cellular material directly into oil is still undeveloped. The unusual amount of oil extracted from the imported fire ant (Solenopsis sp.) may be an indication of the presence of oleaginous microorganisms or enzymes supporting the digestion of raw sugars. Yield of the ant oil is 16% dry weight and contains most of the fatty acids also found in other biomass resources. Heat of combustion of the ant oil was 133,000BTU/gal, an amount within the range of reported values for vegetable oil and biodiesel. This investigation also explores the potential source of the oil through stable isotope labeling and offers a unique perspective of a potentially new source of microorganisms or enzymes useful for reducing the cost of producing an alternative fuel.

Evaluation of biodiesel blending, engine performance and emissions characteristics of Jatropha curcas methyl ester: Malaysian perspective

Currently, the main crop for biodiesel in Malaysia is palm oil. Recently, Jatropha curcas has drawn the attention of the Malaysian Government. This paper aims to study the feasibility of Jatropha as a potential biodiesel feedstock for Malaysia. Physico-chemical properties of Jatropha biodiesel and its blends with diesel followed by engine performance and emissions characteristics of B10, B20 and B0 were studied. The results show that viscosities of B10 and B20 are closer to diesel. Moreover, only the oxidation stability of B10 and B20 meet the European specifications (EN 590) of 20 h. Therefore, only B10 and B20 have been used to evaluate engine performance and emission. Compared to B0, the average reduction in brake power (BP) is 4.67% for B10 and 8.86% for B20. It was observed that brake specific fuel consumption (BSFC) increases as the percentage of biodiesel increase. Compared to B0, a reduction in hydrocarbon (HC) emission of 3.84% and 10.25% and carbon monoxide (CO) emission of 16% and 25% was reported using B10 and B20. However, the blends give higher nitrogen oxides (NOx) emission of 3% and 6% using B10 and B20. As a conclusion, B10 and B20 can be used in a diesel engine without any modifications.

Microalgae-based biodiesel: Economic analysis of downstream process realistic scenarios

Microalgae oil has been identified as a reliable resource for biodiesel production due to its high lipid productivity and potential cultivation in non-fertile locations. However, high scale production of microalgae based biodiesel depends on the optimization of the entire process to be economically feasible. The selected strain, medium, harvesting methods, etc., sorely affects the ash content in the dry biomass which have a direct effect in the lipid content. Moreover, the suitable lipids for biodiesel production, some of the neutral/saponifiable, are only a fraction of the total ones (around 30% dry base biomass in the best case). The present work uses computational tools for the modeling of different scenarios of the harvesting, oil extraction and transesterification. This rigorous modeling approach detects process bottlenecks that could have led to an overestimation of the potentiality of the microalgae lipids as a resource for the biodiesel production.

Evaluation of oil-producing algae as potential biodiesel feedstock

This study attempted to connect the dots between laboratory research and the outdoors. Chlorella sp. NJ-18 was selected among seven oil-producing algae cultivated in this study because it had the highest lipid productivity. The nitrogen and phosphorus concentrations for cultivating this Chlorella strain were optimized indoors. This strain was incubated outdoors in a 70L photobioreactor, containing the favorable nitrogen (8.32mM urea) and phosphorus (0.18mM monopotassium phosphate) concentrations. Semi-continuous cultivation was performed by harvesting 30L biomass and replacing it with fresh medium. The maximum biomass and lipid productivity acquired outdoors were 91.84 and 24.05mgL−1d−1, respectively. Furthermore, biomass productivity could be maintained at a high level throughout the cultivation process when using the semi-continuous mode, whereas it decreased dramatically in batch cultures. More than 95% of the total fatty acids obtained were C16 and C18, which are the main components for biofuel.

Predicting the higher heating values of waste frying oils as potential biodiesel feedstock

In the literature, there are several empirical models to estimate the higher heating values of vegetable oils and biodiesel fuels. In this study, five of these models found in the literature were used to estimate the higher heating value of waste frying oils. When some models are used to estimate HHVs of waste frying oils, the relative errors were found up to 5% compared to the values obtained experimentally. Therefore, a new empirical formula based on the fatty acid composition was developed to predict the HHV of waste frying oils. For this purpose, 35 samples taken from different facilities producing waste frying oils (fast-foods, fish restaurants and hospital restaurants) were analyzed and their properties (such as viscosity, density, iodine value, saponification value, HHV and fatty acid distributions) were determined. Subsequently, to develop an empirical formula, a regression analysis was performed between the HHVs and fatty acid compositions of the waste frying oils. When the experimentally determined and estimated values were compared, it was proven that the new empirical formula gave precise results. By using this model, the mean absolute and relative errors were found around 148.40kJ/kg and 0.37%, respectively.

Comparative Study of the Physicochemical Characterization of Some Oils as Potential Feedstock for Biodiesel Production

Physicochemical properties of Cucurbita pepo, Brachystegia eurycoma, Cucumis melo, Luffa cylindrica, and Arachis hypogaea oils were studied to determine their potential as viable feedstock for biodiesel production. The nonedible oils were extracted by solvent extraction using n-hexane while the oil of Arachis hypogaea was procured. All the oils were characterized for specific gravity, pH, ash content, iodine value, acid value, saponification value, peroxide value, free fatty acid, flash point, kinematic viscosity, and refractive indices using standard methods. Cucurbita pepo seeds had very high oil content when compared to the others. Specific gravity and flash point of the oils were satisfactory. However, moisture content of some of the oils exceeded the stipulated ASTM standard for biodiesel production. Again, acid values of the nonedible oils were very high and exceeded the ASTM standard. They also exceeded the acid value of Arachis hypogaea oil except for Luffa cylindrica oil. Results indicate that the oils are potential biodiesel feedstocks. However, overall results indicate that the nonedible oils are not suitable for single-stage transesterification process to biodiesel but would be better suited for the two stage esterification and subsequent transesterification in order to obtain reasonable yields of the methyl esters.

Evaluation of single cell oil (SCO) from a tropical marine yeast Yarrowia lipolytica NCIM 3589 as a potential feedstock for biodiesel

Single cell oils (SCOs) accumulated by oleaginous yeasts have emerged as potential alternative feedstocks for biodiesel production. As lipid accumulation is species and substrate specific, selection of an appropriate strain is critical. Five strains of Y. lipolytica, a known model oleaginous yeast, were investigated to explore their potential for biodiesel production when grown on glucose and inexpensive wastes. All the strains were found to accumulate > 20% (w/w) of their dry cell mass as lipids with neutral lipid as the major fraction when grown on glucose and on wastes such as waste cooking oil (WCO), waste motor oil (WMO). However, amongst them, Y. lipolytica NCIM 3589, a tropical marine yeast, exhibited a maximal lipid/biomass coefficient, YL/X on 30 g L-1 glucose (0.29 g g-1) and on 100 g L-1 WCO (0.43 g g-1) with a high content of saturated and monounsaturated fatty acids similar to conventional vegetable oils used for biodiesel production. The experimentally determined and predicted biodiesel properties of strain 3589 when grown on glucose and WCO, such as density (0.81 and 1.04 g cm-3), viscosity (4.44 and 3.6 mm2 s-1), SN (190.81 and 256), IV (65.7 and 37.8) and CN (56.6 and 50.8) are reported for the first time for Y. lipolytica and correlate well with specified standards. Thus, the SCO of oleaginous tropical marine yeast Y. lipolytica NCIM 3589 could be used as a potential feedstock for biodiesel production.

Optimizing a continuous flow lipid extraction system (CFLES) used for extracting microalgal lipids

AbstractA laboratory‐made continuous flow lipid extraction system (CFLES) was devised to extract lipids from microalgae Nannochloropsis sp., a potential feedstock for biodiesel fuel, with a focus to assess the workable temperatures and pressures for future industrial applications. Using conventional solvents, the CFLES recovered 100% of the lipids extracted with conventional Soxhlet extraction. The optimum temperature and pressure were found to be 100 °C and 50 psi, respectively; conditions significantly lower than those normally used in pressurized liquid extractions requiring specialized equipment. Approximately 87% of the extracted oil was successfully transesterified into biodiesel fuel (fatty acid methyl esters). Preliminary calculations based on the tested lab‐scale system indicated savings in energy, solvent consumption, and extraction time as 96%, 80%, and more than 90%, respectively, as compared to Soxhlet extraction. However, the true cost savings can only be assessed at scaled up level. Energy efficiency of CFLES was calculated as 48.9%. Residual water (~70%) in the biomass had no effect on the extraction performance of CFLES, which is expected to help the process economics at scaled up application. The effect of temperature and pressure on the fatty acids profile of Nannochloropsis sp. is also discussed. Based on the existing literature, the authors believe that a pressurized liquid extraction system with continuous solvent flow has not been reported for lipid extraction from Nannochloropsis sp.

UJI KINERJA BIODIESEL DARI MINYAK BIJI KARET

<div class="WordSection1"><p><strong>Abstract: </strong><em>The increasing of national biodiesel-demand is not balanced with national production. Two of the reasons are using edible oil as feedstock and high production cost.</em> <em>Seventy percents of production cost comes from raw materials.</em> <em>Exploration of new crops and unexploited oil crops is needed to develop. We could use low-valued feed stocks such as unrefined vegetable oil, waste frying oil, or side product from vegetable oil hydrolysis, the fatty acids. Rubber seed is a potential feedstock for biodiesel in Indonesia, because it is one of the greatest producers in the world. Besides, rubber seed has high proportion of oil and has not been used optimally yet. By using a proper pre-treatment, we could produce high quality biodiesel. The aim of this third-year research is to produce biodiesel in the optimum condition, and analysed it with Engine Test Bed. The optimum conditions are: acid pre-treatment (using H<sub>2</sub>SO<sub>4</sub> on 2.5% v/v as catalyst on the ratio of methanol to oil is 6:1, 60 <sup>o</sup>C), and the second step, alkaline (KOH) catalysed trans-esterification (which was processed in 1 hour, 2% catalyst, 50<sup>o</sup>C, on the ratio of methanol to oil is 6:1). Biodiesel was refined by settling, washing and adsorption. Based on previous research, we concluded that biodiesel from rubber seed oil with acid pre-treatment has lower carbon residue and higher flash point as the advantages. So, it was analyzed in an Engine Test Bed on this research. Biodiesel resulted better performance for B10 than petroleum diesel-fuel in lower rotation (< 2000 rpm), lower fuel-consumption and lower waste-gas flow rate. </em><strong></strong></p><p><strong><em>Keywords: </em></strong><em>acid pre-treatment, biodiesel, Engine Test Bed, fatty acids, rubber seed oil</em></p></div><strong><br clear="all" /></strong>

PENGGESERAN REAKSI KESETIMBANGAN HIDROLISIS MINYAK DENGAN PENGAMBILAN GLISEROL UNTUK MEMPEROLEH ASAM LEMAK JENUH DARI MINYAK BIJI KARET

<p>Abstract: Indonesia is one of the largest rubber producers in the world. Rubber seed is obtained<br />as agricultural waste. This is a potential feedstock for biodiesel because of its high proportion of<br />oil. The oil is hydrolyzed to produce saturated and unsaturated fatty acids. Unsaturated fatty acids<br />such as oleic, linoleic and linolenic acids are good for health. Besides, saturated fatty acids are<br />suitable for high-quality biodiesel by esterification. Batch process of rubber seed hydrolysis was<br />conducted on this research to produce fatty acids and glycerine. In case of its reversible reaction,<br />continuously separation of product or increasing reactant-concentration was needed to achieve<br />equilibrium conversion. In this batch process, continuously separation of glycerine was done by<br />settling it stage by stage (multi stages). The objection of this research was to find optimum<br />condition on multi stages hydrolysis to produce fatty acids. It was processed on hydrochloric-acid<br />catalyzed, fifty-fifty ratio of oil and water, and reacted in 70<br />C. In each stage of hydrolysis,<br />glycerine and water was separated from reaction mixture by settling on 24 hours. The fatty acids<br />were re-hydrolyzed with fresh water like the stage before. The process was stopped while it<br />reached maximum conversion (almost completely). Based on this research, we concluded that<br />for the shorter time of each stage on hydrolysis-process gives higher conversion of oil to fatty<br />acids.<br />o<br />Keywords: fatty acids, multi stages hydrolysis, Rubber Seed Oil, reaction equilibrium.</p>

Increase in lipids production by Pichia angusta DL-1 utilizing the chemostat under double limitation of heterologous nutrients

For many years there has been industrial interest to produce microbial oils through oleaginous microorganisms. Its fatty acids composition is similar to vegetable oils, so that the use of microbial polyunsaturated fatty acids has been very important in animal nutrition and is currently considered the potential feedstock for biodiesel, therefore any significant improvement in the process of lipid synthesis will reduce costs of production at industrial level. We investigated the use chemostat under different heterologous double nutrient limitations, that is, nutrients that meet different physiological requirements, in order to achieve a higher production lipid accumulation in oleaginous yeast. We used Pichia angusta DL-1 grown in a chemostat under carbon/phosphorus, carbon/magnesium, nitrogen/phosphorus and nitrogen/magnesium double limitations at five different dilution rates. The largest accumulation of lipids occurred under nitrogen/phosphorus limitation at a dilution rate of 0.03h−1 and carbon/magnesium limitation at a dilution rate of 0.07h−1. At that condition lipid content was twice the one obtained in batch culture and 15% larger than under simple limitation. Finally, under carbon/magnesium limitation the highest lipid productivity (0.011g/Lh) was obtained with a cell productivity of 0.033g/Lh.

Single cell oil of oleaginous fungi from the tropical mangrove wetlands as a potential feedstock for biodiesel

BackgroundSingle cell oils (SCOs) accumulated by oleaginous fungi have emerged as a potential alternative feedstock for biodiesel production. Though fungi from mangrove ecosystem have been reported for production of several lignocellulolytic enzymes, they remain unexplored for their SCO producing ability. Thus, these oleaginous fungi from the mangrove ecosystem could be suitable candidates for production of SCOs from lignocellulosic biomass. The accumulation of lipids being species specific, strain selection is critical and therefore, it is of importance to evaluate the fungal diversity of mangrove wetlands. The whole cells of these fungi were investigated with respect to oleaginicity, cell mass, lipid content, fatty acid methyl ester profiles and physicochemical properties of transesterified SCOs in order to explore their potential for biodiesel production.ResultsIn the present study, 14 yeasts and filamentous fungi were isolated from the detritus based mangrove wetlands along the Indian west coast. Nile red staining revealed that lipid bodies were present in 5 of the 14 fungal isolates. Lipid extraction showed that these fungi were able to accumulate > 20% (w/w) of their dry cell mass (4.14 - 6.44 g L-1) as lipids with neutral lipid as the major fraction. The profile of transesterified SCOs revealed a high content of saturated and monounsaturated fatty acids i.e., palmitic (C16:0), stearic (C18:0) and oleic (C18:1) acids similar to conventional vegetable oils used for biodiesel production. The experimentally determined and predicted biodiesel properties for 3 fungal isolates correlated well with the specified standards. Isolate IBB M1, with the highest SCO yield and containing high amounts of saturated and monounsaturated fatty acid was identified as Aspergillus terreus using morphotaxonomic study and 18 S rRNA gene sequencing. Batch flask cultures with varying initial glucose concentration revealed that maximal cell biomass and lipid content were obtained at 30gL-1. The strain was able to utilize cheap renewable substrates viz., sugarcane bagasse, grape stalk, groundnut shells and cheese whey for SCO production.ConclusionOur study suggests that SCOs of oleaginous fungi from the mangrove wetlands of the Indian west coast could be used as a potential feedstock for biodiesel production with Aspergillus terreus IBB M1 as a promising candidate.

Expression of fatty acid synthesis genes and fatty acid accumulation in haematococcus pluvialis under different stressors

BackgroundBiofuel has been the focus of intensive global research over the past few years. The development of 4th generation biofuel production (algae-to-biofuels) based on metabolic engineering of algae is still in its infancy, one of the main barriers is our lacking of understanding of microalgal growth, metabolism and biofuel production. Although fatty acid (FA) biosynthesis pathway genes have been all cloned and biosynthesis pathway was built up in some higher plants, the molecular mechanism for its regulation in microalgae is far away from elucidation.ResultsWe cloned main key genes for FA biosynthesis in Haematococcus pluvialis, a green microalga as a potential biodiesel feedstock, and investigated the correlations between their expression alternation and FA composition and content detected by GC-MS under different stress treatments, such as nitrogen depletion, salinity, high or low temperature. Our results showed that high temperature, high salinity, and nitrogen depletion treatments played significant roles in promoting microalgal FA synthesis, while FA qualities were not changed much. Correlation analysis showed that acyl carrier protein (ACP), 3-ketoacyl-ACP-synthase (KAS), and acyl-ACP thioesterase (FATA) gene expression had significant correlations with monounsaturated FA (MUFA) synthesis and polyunsaturated FA (PUFA) synthesis.ConclusionsWe proposed that ACP, KAS, and FATA in H. pluvialis may play an important role in FA synthesis and may be rate limiting genes, which probably could be modified for the further study of metabolic engineering to improve microalgal biofuel quality and production.

Metabolic profiling reveals growth related FAME productivity and quality of Chlorella sorokiniana with different inoculum sizes

Inoculum size strongly affects cell growth and lipid accumulation of microalgae, one of the most potential biodiesel feedstock, however, the metabolic mechanism(s) of the lipid biosynthesis upon inoculum size has not been fully explored yet. The effects of inoculum size on cell growth, lipid accumulation, and metabolic changes of a green microalga Chlorella sorokiniana were investigated. In our experimental range of inoculum size, the productivity and the cetane number (CN) of fatty acid methyl esters (FAME) increased with increasing initial cell density, and the inoculum of 1 × 10(7) cells mL(-1) processed much higher productivity (up to 2.02-fold) and CN (up to 1.19-fold) of the FAME than the others. A significant correlation between the metabolic profile and quantity and quality of lipid production was revealed by partial least-squares to latent structures (PLS) analysis, and 15 key metabolites were identified. Most of those metabolites were involved in the photosynthetically fixed carbon metabolism. Furthermore, light intensity as one of the vital limitation factors for the high inoculum size cultivation was evaluated by illumination assay and the results revealed that increasing light intensity could improve the polyunsaturated fatty acids composition and lipid accumulation of C. sorokiniana. The lipid productivity of the culture was improved by 71.21% with the light intensity of 110 µmol m(-2) s(-1), compared to that under the irradiance of 65 µmol m(-2) s(-1).

Probing Wisconsin highbush cranberry (V. trilobum), dotted horsemint (M. punctata), and American hazelnut (C. americana) as potential biodiesel feedstocks

The need for biodiesel feedstocks growing on non-arable lands is widely recognized. We present results of the synthesis and characterization of new biodiesels we produced from oils of highbush cranberry, dotted horsemint, and American hazelnut growing in Northern Wisconsin. These biodiesels, particularly those derived from highbush cranberry, exhibited remarkably good low-temperature properties, a condition that is crucial for wider usage of any biodiesel in cold climates. We also present the results on determination of the oxidative stability of the above biodiesels and discuss the growing conditions and habitats of the related plants.

Process optimization design for jatropha-based biodiesel production using response surface methodology

Biodiesel of non food vegetal oil origin is gaining attention as a replacement for current fossil fuels as its non-food chain interfering manufacturing processes shall prevent food source competition which is expected to happen with current biodiesel production processes. As a result, non edible Jatropha curcas plant oil is claimed to be a highly potential feedstock for non-food origin biodiesel. CaO–MgO mixed oxide catalyst was employed in transesterification of non-edible J. curcas plant oil in biodiesel production. Response surface methodology (RSM) in conjunction with the central composite design (CCD) was employed to statistically evaluate and optimize the biodiesel production process. It was found that the production of biodiesel achieved an optimum level of 93.55% biodiesel yield at the following reaction conditions: 1) Methanol/oil molar ratio: 38.67, 2) Reaction time: 3.44 h, 3) Catalyst amount: 3.70 wt.%, and 4) Reaction temperature: 115.87 °C. In economic point of view, transesterification of J. curcas plant oil using CaO–MgO mixed oxide catalyst requires less energy which contributed to high production cost in biodiesel production. The incredibly high biodiesel yield of 93.55% was proved to be the synergetic effect of basicity between the active components of CaO–MgO shown in the physicochemical analysis.

An Economic Evaluation of Soybean-Based Biodiesel Production on Commercial Farms in Kwazulu-Natal, South Africa

Global biofuel production has risen substantially in recent years, driven primarily by government support for biofuel industries. The stated motivations for these initiatives are numerous and have varied over time. Soybeans are the only field crop produced in sufficient quantities in the province of KwaZulu-Natal (KZN) that the South African industrial biofuel strategy identifies as a potential biodiesel feedstock. Results from a mixed integer linear programming model suggest that significant government support is required to stimulate biodiesel production, and support the notion of Funke et al. (2009), who contend that the incentives and commitments outlined by the industrial biofuel strategy are inadequate to both establish and sustain a domestic biodiesel industry. Under baseline assumptions, a minimum implicit subsidy of R4.37 per litre is required to draw soybean-based biodiesel production into the optimum solution. Results also show that the implicit subsidy is sensitive to changes in the soybean oilcake (by-product) price and the soybean (input) price.

Analysis of expressed sequence tags from biodiesel plant Jatropha curcas embryos at different developmental stages

Jatropha curcas is considered a potential biodiesel feedstock plant whose seeds contain up to 40% oil. However, little is currently known about the seed biology of Jatropha. Therefore, it would be valuable to understand the mechanisms of development and lipid metabolism in Jatropha seeds. In the present study, three cDNA libraries were constructed with mRNA from Jatropha embryos at different stages of seed development. A total of 9844 expressed sequence tags (ESTs) were produced from these libraries, from which 1070 contigs and 3595 singletons were obtained. One hundred and seven unigenes were found to be differentially expressed in the three cDNA libraries of Jatropha embryos, indicating that these genes may play key roles in seed development. We have identified 59 and 61 unigenes that might be involved in the development and lipid metabolism in Jatropha seeds, respectively. Some of these genes may also play important roles in embryogenesis, morphogenesis, defense response and adaptive mechanisms in plants.

Green microalga Chlorella vulgaris as a potential feedstock for biodiesel

AbstractBACKGROUND: A major bottleneck in microalgal biodiesel production is lipid content, which is often low in microalgal species. The present study examines Chlorella vulgaris as a potential feedstock for biodiesel by identifying and evaluating the relationships between the critical variables that enhance the lipid yield, and characterizes the biodiesel produced for various properties.RESULTS: Factors affecting lipid accumulation in a green microalga, Chlorella vulgaris were examined. Multifactor optimization raised the lipid pool to 55% dry cell weight against 9% control. When C. vulgaris cells pre‐grown in glucose (0.7%)‐supplemented medium were transferred to the optimized condition at the second stage, the lipid yield was boosted to 1974 mg L−1, a value almost 20‐fold higher than for the control. The transesterified C. vulgaris oil showed the presence of ∼82% saturated fatty acids, with palmitate and stearate as major components, thus highlighting the oxidative stability of C. vulgaris biodiesel. The fuel properties (density, viscosity, acid value, iodine value, calorific value, cetane index, ash and water contents) are comparable with the international (ASTM and EN) and Indian (IS) biodiesel standards.CONCLUSION: C. vulgaris biomass with 55% lipid content and adequate fuel properties is potentially a renewable feedstock for biodiesel. Copyright © 2011 Society of Chemical Industry