Characterization and Identification of Oleaginous Microalgae Isolated from Fresh Water for Biodiesel Production

The biodiesel can be produced from diverse microalgae lipids as alternative and renewable fuel. Thus, the aim of this study was to optimize the Chlamydomonas reinhardtii promising species as biodiesel feedstock for large-scale cultivation in Egypt. To understand some of the triggers required for the metabolic pathway switch to lipid accumulation, the effect of carbon sources and the three elements availability (N, P, S) in C. reinhardtii growth medium was determined. A local microalgae C. reinhardtii was cultured in modified Sueoka medium containing various concentrations of CO2 and bicarbonate (NaHCO3) (in 2-liter flasks) as a carbon source. The optimal source in term biomass, high lipid productivity (10.3 mgL-1d-1) and a higher lipid content (22.76%) were obtained in 6% CO2 culture. Then, the availability of N, P, S (various concentrations of N, P and S) nutrients elements was added to 6% CO2 culture, for produce a highest lipid content and lipid productivity. As expected, under low availability N-1.78 mM; P-0.14mM and S-0.10 mM mediums, C. reinhardtii showed a high accumulation lipid content. Therefore, to improve the economic feasibility of microalgae biofuels production, its concentrations were selected to combine (N+P+S) in order to cultivation of C. reinhardtii in a multi-tubular photobioreactor (400 liter) to produce high lipid contents. Under limited condition, the biomass dry weight, biomass productivity, lipid content and lipid productivity were found to be 3.11 (gL-1), 0.15±0.012 (g-1L-1d-1), 22.76% (w/w %) and 1.9± 0.35 (mg-1L-1d-1), respectively. The extracted lipid was found to have physical and chemical properties similar that plant oils using for biodiesel production. The FAME profiling of prepared biodiesel shows the presence of considerable amount of 36.97% saturated fatty acids (palmitic acid and stearic acid, together) with 27.33% unsaturated (oleic acid and linoleic acid) fatty acids. The FAME had a low iodine value and high CN, which meet with the appropriate of biodiesel standards (EN 14214 and ASTM D6751). Thus, C. reinhardtii appears to be more feasible for high quality biodiesel production.

Mixed microalgae consortia growth under higher concentration of CO2 from unfiltered coal fired flue gas: Fatty acid profiling and biodiesel production

The performance of a self-flocculating microalga Chlorococcum sp. GD on the flocculation, growth, and lipid accumulation in wastewater with different ammonia nitrogen concentrations was investigated. It was revealed that relative high ammonia nitrogen concentration (20–50 mg·L−1) was beneficial to the flocculation of Chlorococcum sp. GD, and the highest flocculating efficiency was up to 84.4%. It was also found that the highest flocculating efficiency occurred in the middle of the culture (4–5 days) regardless of initial ammonia concentration in wastewater. It was speculated that high flocculating efficiency was likely related to the production of extracellular proteins. 20 mg·L−1 of ammonia was found to be a preferred concentration for both biomass production and lipid accumulation. 92.8% COD, 98.8% ammonia, and 69.4% phosphorus were removed when Chlorococcum sp. GD was cultivated in wastewater with 20 mg·L−1 ammonia. The novelty and significance of the investigation was the integration of flocculation, biomass production, wastewater treatment, and lipid accumulation, simultaneously, which made Chlorococcum sp. GD a potential candidate for wastewater treatment and biodiesel production if harvested in wastewater with suitable ammonia nitrogen concentration.

CHANGES in analytical characteristics following upon the onset of rancidity in butters and butterfats have been widely studied1–6, with somewhat discrepant results. This is scarcely surprising in view of the number of variables involved, within the material itself and in the conditions of its spoilage. In the work here reported, the samples of ghee were prepared with some care and represent genuine products in good condition ; the specimens examined were not chosen at random but belonged to three definite types—one, from Kirkee, of high Reichert value (30–40) and low iodine value (c. 28) typical of well-kept dairy buffaloes, another of normal Reichert value (c. 25) and iodine value (c. 38) from dairy cows, and the third of low Reichert value (14–22) and high iodine value (33–40) derived from buffaloes fed mainly on cotton-seed. The samples had all been stored in similar conditions, namely, in glass bottles with fairly loose-fitting wooden corks placed in a laboratory cupboard for periods of three to four years at a temperature range of 15–25° C. The analytical characteristics of the samples were determined before and after storage, and the average changes in each group were as below.

Biodiesel has been gaining huge attention as an alternative to petrodiesel over the past decades, mainly due to its striking economic and environmental benefits. An integrated feedstock supply chain and production technology play a crucial role in a sustainable and economically feasible biodiesel adoption all over the world. Biodiesel can be produced from various vegetable oils, animal fats, and microbial oils, but when it comes to economic and commercial production, second generation feedstock becomes the major choice of raw material. Moringa oleifera is one such promising feedstock for biodiesel production due to its high ‘cetane number’ (CN), high oxidation stability, and low iodine value with a large fraction of unsaturated fatty acids, and its widely distributed perennial tree. But the high acid value makes it unfit for direct transesterification. This chapter highlights the available feedstocks as well as the potential of ‘Moringa oleifera oil’ (MOO) for biodiesel production and efficiency of ultrasonication; a case study is performed on the ultrasound assisted acid catalyzed esterification of MOO.

Sustainable biodiesel production from microalgae Graesiella emersonii through valorization of garden wastes-based vermicompost

The wastewater concentration is commonly acceptable for macroalgae growth; this process consumes water and is applicable for bioremediation. This study evaluated biodiesel's potential production from freshwater macroalga, Nitella sp., using batch experiment. Algae were collected from wastewater saturated from irrigation canals. Water quality and algae growth environment characteristics were monitored and analyzed. COD and BOD values were 18.67 ± 4.62 mg/L and 5.40 ± 0.30 mg/L, respectively. The chemical composition contents were high, demonstrating that water quality and sufficient nutrients could support algae growth. Oil extraction was estimated by the room temperature and heat extraction methods. The biodiesel in room temperature treatment was 0.0383 ± 0.014%, and in heat, extraction treatment was 0.0723 ± 0.029%. Results confirmed that the heat extraction treatment gave a high amount of oil and biodiesel yield. Gas chromatography/mass spectrometry (GC/MS) was used to analyze fatty acid methyl esters (FAME). Results revealed that 9-octadecane was a major portion of the substance. The obtained results confirmed that the wastewater contains many elements that can be utilized for dual-mode, like bioremediation and enhanced macroalgae growth for biodiesel production. Therefore, macroalgae grown in canal wastewater were highly feasible for use in sustainable biodiesel production.

Novel mutant camelina has become a crop of interest inspired by its short growing season, low harvesting costs and high oil composition. Despite those advantages, limited research has been done on novel mutant lines to determine applicability for biodiesel production. Jatropha is an extremely hardy, frugal and high oil yielding plant species. The major aim of the present study was not only to compare biodiesel production from jatropha and camelina but was also to test the efficacy of camelina mutant lines (M6 progenies) as superior feedstock. The biodiesel yield from camelina oil and jatropha oil was 96% and 92%, respectively. The gas chromatographic analysis using flame ionization detector (GC-FID) showed that mutant camelina oil biodiesel sample contain major amount of oleic acid (46.54 wt%) followed by linolenic acid (20.41 wt%) and linoleic acid (16.55 wt%). Jatropha biodiesel found to contain major amount of oleic acid (45.03 wt%) followed by linoleic acid (25.07 wt%) and palmitic acid (19.31 wt%). The fuel properties of produced biodiesel were found in good agreement with EN14214 and ASTM D6751 standards. The mutant camelina lines biodiesel have shown comparatively better fuel properties than jatropha. It has shown low saponification value (120.87–149.35), high iodine value (130.2–157.9) and better cetane number (48.53–59.35) compared to jatropha biodiesel which have high saponification value (177.39–198.9), low iodine value (109.7–123.1) and lesser cetane number (47.76–51.26). The results of the present student of utilizing novel mutant camelina lines for biodiesel production are quite promising and are helpful in turning out the outcomes of the previous studies suggesting that C. sativa biodiesel presents serious drawbacks for biodiesel applications.

Because of the increasing number of power plants, automobiles, and factories, the increase in these automobiles and power plants produces more emissions of CO, HC, and NOx. The world is searching for an alternative fuel that will not harm the environment and will be less costly. Biodiesel is one of the leading solutions to the global energy crisis, nonetheless, production from food-grade oils is not economically feasible due to high prices. Almost 80-85% of biodiesel is feedstocks. Presently, the use of non-edible waste oils is unable to support large-scale biodiesel production. Therefore, the search for other non-edible oil-bearing feedstocks should be continued. The present investigation attempts to use non-edible tamarind seed oil as an inexpensive, sustainable, and potent feedstock for biodiesel synthesis. Tamarind seed oil was converted to biodiesel by acid (HCl), base (KOH), and enzyme-catalysed transesterification. Tamarind seed biodiesel was found to have a low iodine value (27-33) and a high cetane number (66-68). The catalyst was characterised through acid, base, and enzyme catalysis, and the biodiesel was analysed using GC-MS and FTIR. The highest biodiesel yield of 96.57 ± 0.81 % was achieved in 3.35 ± 0.15 h under optimal conditions of a 9:1 molar ratio of methanol to oil (MRMO) and a 15 wt% catalyst concentration at a temperature of 65°C. The reusability of the catalyst was successfully examined up to the third cycle, with 82.76 ± 0.80 % biodiesel. The feasibility of the resultant methyl esters was verified through chromatography-mass spectrometry (GC-MS) analyses. The developed catalyst can be considered an active catalyst, benefiting from its cost-effectiveness and environmentally friendly nature.

Production of biodiesel from low priced, renewable and abundant date seed oil

As a result of a recent ad hoc prospection of the Algerian territory, a collection of peanut (groundnut; Arachis hypogaea L.) landraces was established, covering a remarkable array of diversity in terms of morphological and physiological features, as well as of adaptation to local bioclimatic conditions. In the present work, the oils extracted from the seeds of these landraces were evaluated in terms of edible properties and suitability for biodiesel production. As for edible use, a low free acidity (ranging from 0.62 to 1.21%) and a high oleic acid content (44.61-50.94%) were common features, although a poor stability to oxidation [high peroxide values, high spectrophotometric indices, and low % of inhibition in the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH)· test] was observed in a few cases. As for biodiesel production, low values of acidity [1.23-2.40 mg KOH (g oil)(-1)], low iodine values [90.70-101.54 g I2 (g oil)(-1)], high cetane numbers (56.95-58.88) and high calorific values (higher heating value 37.34-39.27 MJ kg(-1)) were measured. Edible properties and suitability for biodiesel production were discussed with respect to the German standard DIN 51605 for rapeseed oil and to the EN 14214 standard, respectively. One way ANOVA and Hierarchical Cluster Analysis showed significant differences among the oils from the Algerian peanut landraces.

The production of biodiesel through chemical production processes of transesterification reaction depends on suitable catalysts to hasten the chemical reactions. Therefore, the initial selection of catalysts is critical although it is also dependent on the quantity of free fatty acids in a given sample of oil. Earlier forms of biodiesel production processes relied on homogeneous catalysts, which have undesirable effects such as toxicity, high flammability, corrosion, by‐products such as soap and glycerol, and high wastewater. Heterogeneous catalysts overcome most of these problems. Recent developments involve novel approaches using biomass and bio‐waste resource derived heterogeneous catalysts. These catalysts are renewable, non‐toxic, reusable, offer high catalytic activity and stability in both acidic and base conditions, and show high tolerance properties to water. This review work critically reviews biomass‐based heterogeneous catalysts, especially those utilized in sustainable production of biofuel and biodiesel. This review examines the sustainability of these catalysts in literature in terms of small‐scale laboratory and industrial applications in large‐scale biodiesel and biofuel production. Furthermore, this work will critically review natural heterogeneous biomass waste and bio‐waste catalysts in relation to upcoming nanotechnologies. Finally, this work will review the gaps identified in the literature for heterogeneous catalysts derived from biomass and other biocatalysts with a view to identifying future prospects for heterogeneous catalysts.

Comparison of integrated sustainable biodiesel and antibacterial nano silver production by microalgal and yeast isolates

The study was conducted to evaluate the conditions to enhance the accumulation of lipids and starch in Chlorococcum sp. TISTR 8583 for the production of biofuel. The Chlorococcum sp. TISTR 8583 was cultivated on BG-11 medium under optimized light intensity. The nitrogen limitation (NL) enhanced the accumulation of both starch and lipids and resulted in 34.02% total sugars as compared to 22.57% on nitrogen supplemented (NS) media only. Similarly, the nitrogen supplemented (NS) media produced 17.05% lipids as compared to 29.59% lipids by NL media. The biomass was investigated for biodiesel and bioethanol production by adopting different pretreatment strategies, such as enzyme, acid and alkaline pretreatments. The alkaline pretreatment was found to be efficient strategy (23.67 wt% sugars/g algal biomass: 1.2% (w/v) at 140 ⁰C for 30 min) while the acid pretreatment (1%: v/v; 140 °C) was least effective pretreatment strategy with the yield of 14.83 wt% sugars/g algal biomass.

Valorization of abattoir water discharge through phycoremediation for enhanced biomass and biodiesel production