Potential For Biodiesel Production Research Articles

Assessment of Waste Animal Fats (WAFS) Biodiesel Production Potential as an Alternative Fuel for Zambia: A Case Study of Southern Province

The volatility in global fuel prices and the desire to reduce energy dependency on fossil fuels has necessitated the speeding up of alternative energy supply sources. Coupled to this is the global urgent need to reduce the accumulation of CO2 and green house gas (GHG) emissions as a result of fossil fuels production and use. Further, the mandate by united nations to move towards sustainably produced energy for the transportation, and power generation demands that we seek energy solutions that meet reduced negative impact on the environment. It is in this regard that this study seeks alternatives in waste animal fats (WAFs) biodiesel as an option that could meet the ever increasing demand for fossil fuel in the transport sector and power generation. For the transport sector and power generation , the biodiesel maybe blended with the fossil diesel in the approved ratios as stipulated by the Energy Regulation Board and the Zambia Bureau of Standards to help mitigate the net GHG and CO2 emissions. The biodiesel production in this study was based on the modified two-step process. These two steps involved passing the feedstock through esterification using sulphuric acid as catalyst and there after base catalysed using sodium hydroxide in a process referred to as transesterification. The resulting products in the esterification process are the esters and water whilst in the transesterification are the biodiesel and glycerol. The feedstock used are those of waste animal fats (WAFs) of cattle, pig and chicken that has been discarded from meat processing and animal slaughter houses. The feedstocks have been carefully selected based on the animals raised in the country with a bigger slaughtered population as well as reared. The population of animals reared and slaughtered annually are obtained from the Zambia Ministry of Agriculture animal population census records. Based on these records, the preferred feedstock sources where obtained. The study further 1. explored the economic potential of the biodiesel production for the Zambian government and beyond. 2. compared some of the characteristics of WAF biodiesel to that of imported fossil diesel 3. affirmed that WAF biodiesel has a very good impact in reducing environmental pollution as WAF dumping to land fills and the cost of disposal is reduced. Also,WAF biodiesel is bio-degradable. Thus, moving closer to an effective sustainable development as required by the united nations sustainability goals if full scale production is implemented in Zambia.

Integrating environmental remediation with biodiesel production from toxic non-edible oil seeds (Croton bonplandianus) using a sustainable phyto-nano catalyst

In the current situation of the environmental uprising toxicology, rising global temperature, and energy-depleting urges to explore and discover more renewable and greener ecological-benefiting energy resources. Biobased renewable fuels generated by using waste products can help in waste management, climate change mitigation, and a low-carbon future. The main objective of this research is to produce environment-friendly and cost-effective biofuel. The potentiality of the novel, toxic, waste, and inedible feedstock Croton bonplandianus was evaluated for biodiesel synthesis through transesterification utilizing a Phyto-nano catalyst of potassium oxide prepared by Croton bonplandianus floral stalk's aqueous extract focusing on waste management. Phyto-nano catalyst characterization was done through innovative tools such as Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Zeta Potential (ZP), X-Ray Diffraction (XRD), Fourier Transformed Infrared spectroscopy (FTIR), and Diffuse Reflectance Spectroscopy (DRS). The characterization results revealed that the potassium oxide phyto-nanocatalyst possesses an average nanoparticle size of 44.5 nm. This size is optimal for enhanced catalytic activity, indicating significant potential for efficient catalysis. The highest yield (94 %) of biodiesel was secured at optimized reaction conditions of catalyst quantity (0.50 wt%), reaction time (180 min), methanol: oil ratio (9:1), and reaction thermal point (70 °C). Transformation of triglycerides to methyl esters was confirmed by GC/MS, NMR, and FTIR techniques. A total of 21 methyl esters were observed in Croton bonplandianus biodiesel confirmed via GC/MS results. Evaluation of fuel properties was done and matched with international fuel standards. The conclusive remarks for the conducted research are that Croton bonplandianus has a high potential for biodiesel production by applying Phyto-nanocatalysts of potassium oxide while dealing with hazardous environmental conditions and waste management. Phyto nanocatalyst of potassium oxide can be reused and gives the same yield after several cycles of reusability, this reusability of heterogenous Phyto nanocatalyst can reduce to total cost of biodiesel production and can contribute towards circular economy.

Engineering lipase TLL to improve its acid tolerance and its biosynthesis in Trichoderma reesei for biodiesel production from acidified oil

Lipases catalyze the synthesis of biodiesel, which is an important renewable alternative energy source. Cost-efficient conversion of waste acidified oil to biodiesel entails acid-tolerant lipases which have not been extensively studied. This study showed that the commonly used Thermomyces lanuginosus lipase TLL displayed a weak acid tolerance and an unsatisfactory performance in biodiesel production from acidified oil. Directed evolution of TLL identified one TLL-T3 variant with three residue substitutions (A69S/V150P/N222G). TLL-T3 displayed significantly enhanced acid tolerance, and its application in acidified oil treatment led to a biodiesel yield up to 90 % (w/w). A scaled-up production of TLL-T3 in Trichoderma reesei was further achieved and the highest extracellular lipase activity reached 16,123 U/mL after fermentation optimization. These results provide new insights into structural adaptation to acid tolerance by lipases and show that TLL-T3 holds great potential in commercial biodiesel production from waste acidified oil.

Use of plant growth regulators and their combined application to enhance lipid productivity in the filamentous microalga Tribonema sp.

Oleaginous Tribonema sp. has shown great potential in biodiesel production. However, effective strategies are still needed to increase overall lipid productivity for cost-effectiveness. Although the effects of plant growth regulators (PGRs) on enhancing microalgal growth and lipid content have been widely demonstrated, the synergistic effects of their combinations on improving lipid productivity in Tribonema sp. remain unclear. In this study, we investigated the comparative effects of five PGRs (e.g., fulvic acid, melatonin, gibberellin, γ-aminobutyric acid [GABA], and indoleacetic-3-acid [IAA]) at different concentrations (0.1–10 mg/L) on the growth, nitrogen uptake, and lipid content of Tribonema sp. The results showed that 10 mg/L GABA and 0.1 mg/L IAA were optimal conditions, contributing to an approximately 33.00 % increase in lipid productivity compared with the control (without PGRs). Based on these findings, the combination of optimized concentrations of GABA and IAA, especially in equal proportions, resulted in a more desirable fatty acid profile and produced the highest biomass, lipid content, and lipid productivity, with increases of 23.55 %, 25.62 %, and 54.95 %, respectively, over the control. This combination also significantly increased nitrogen removal efficiency in the medium, which was 46.24 % higher that of the control. These results were attributed to the significant upregulation of genes associated with nitrogen metabolism mediated by the synergy of IAA and GABA, promoting nitrate uptake by algal cells in the medium. Genes involved in photosynthesis and lipid synthesis were also upregulated, facilitating simultaneous biomass and lipid accumulation to maximize lipid productivity. Overall, this study is the first to report the combined application of GABA and IAA as an effective strategy to enhance lipid productivity in Tribonema sp., providing insights into the underlying mechanisms. These findings offer a promising solution for economically improving microalgal lipid production.

Enhancement on the lipase activity of M. circinelloides by ARTP mutagenesis for biodiesel production from woody plant oil

The objective is to enhance lipase activity of Mucor circinelloides via atmospheric and room temperature plasma (ARTP). ARTP was employed to treat spores of M. circinelloides for the selection of high lipase producers. With an irradiation time of 100 s at a lethal rate of 95 %, 18 mutants with higher lipase activity were initially selected. Measurements of the lipase activity revealed that a mutant strain LA-26 was characterized by a steady hereditary stability with lipase activity increase to 376.7 U/g. Moreover, the mutant LA-26 was immobilized as whole-cell biocatalyst used in solvent-free system to produce biodiesel. Response surface methodology (RSM) was used to optimize the reaction parameters. With the addition of 8 % biocatalyst, 10 % water content (w/w) and the stepwise addition of methanol (methanol to oil ratio of 4:1), the highest biodiesel (FAME) yield up to 98 % was achieved within 48 h. Immobilized LA-26 can be used for repeated batches, maintaining 70 % FAME yield after 6 cycles. The identified mutant strain LA-26 exhibits great potential for biodiesel production.

Synthesis of the acidic/magnetic catalyst x-MoO3/Ni0.5Zn0.5Fe2O4 by combustion reaction and evaluation of its catalytic potential/reuse in biodiesel production

The objective of this work was to synthesize a new catalyst x-MoO3/Ni0.5Zn0.5Fe2O4 using the combustion reaction method and to evaluate its catalytic potential and reuse in biodiesel production from waste oil, optimizing the process through experimental design. The catalysts were characterized in terms of structure by X-ray diffraction and phase quantification by Rietveld refinement, surface area by the Brunauer-Emmett-Teller technique, experimental density by helium pycnometry, acidity tests by ammonia desorption at programmed temperature, chemical analysis by X-ray fluorescence, morphology by scanning and transmission electron microscopy, and catalytic properties. The products of the simultaneous transesterification and esterification reactions were characterized by gas chromatography and acidity index. The results indicate the formation of catalysts with surface area ranging from 1.5 to 1.7 m2/g and density ranging from 4.5 to 5.1 g/cm3, composed of major crystalline phases of MoO3 in the orthorhombic configuration and cubic Ni0.5Zn0.5Fe2O4 ferrite, with total acidity ranging from 70 to 182 μmol/g of NH3. Morphological characterization revealed that the catalyst comprises irregular plates of various sizes and shapes with a wide range of cluster sizes. In the simultaneous transesterification and esterification reactions of residual oil, the catalysts were active under all conditions tested, with emphasis on the catalyst containing 50 % Mo ions and 50 % Ni0.5Zn0.5Fe2O4 presenting the best catalytic performance with a conversion of 95 % in ethyl esters and a reduction of 71 % in acidity, with a service life of 6 cycles, an average conversion of 90 % and good thermal and structural stability after use. The experimental design was significant and predictive, with a confidence level of 95 %. Statistical analysis identified that all input variables (temperature, time, and amount of catalyst) were significant for the adopted design. The new catalyst composed of molybdenum, iron, nickel, and zinc has a positive impact on biodiesel synthesis from frying oil and ethanol.

Biodiesel Production from Waste Cooking Oil Using Recombinant Escherichia coli Cells Immobilized into Fe3O4-Chitosan Magnetic Microspheres.

Developing reusable and easy-to-operate biocatalysts is of significant interest in biodiesel production. Here, magnetic whole-cell catalysts constructed through immobilizing recombinant Escherichia coli cells (containing MAS1 lipase) into Fe3O4-chitosan magnetic microspheres (termed MWCC@MAS1) were used for fatty acid methyl ester (FAME) production from waste cooking oil (WCO). During the preparation process of immobilized cells, the effects of chitosan concentration and cell concentration on their activity and activity recovery were investigated. Optimal immobilization was achieved with 3% (w/v) chitosan solution and 10 mg wet cell/mL cell suspension. Magnetic immobilization endowed the whole-cell catalysts with superparamagnetism and improved their methanol tolerance, enhancing the recyclability of the biocatalysts. Additionally, we studied the effects of catalyst loading, water content, methanol content, and reaction temperature on FAME yield, optimizing these parameters using response surface methodology and Box-Behnken design. An experimental FAME yield of 89.19% was gained under the optimized conditions (3.9 wt% catalyst loading, 22.3% (v/w) water content, 23.0% (v/w) methanol content, and 32 °C) for 48 h. MWCC@MAS1 demonstrated superior recyclability compared to its whole-cell form, maintaining about 86% of its initial productivity after 10 cycles, whereas the whole-cell form lost nearly half after just five cycles. These results suggest that MWCC@MAS1 has great potential for the industrial production of biodiesel.

Biofuel production utilizing black soldier fly (Hermetia illucens): a sustainable approach for organic waste management

This study investigates the potential of biodiesel production from Black Soldier Fly (BSF) larvae using organic waste. The aim of this research is to assess the feasibility of biodiesel production and its economic viability from BSF larvae. Specific objectives include analyzing organic waste quantity, moisture content, dry matter, BOD content, and biodiesel conversion efficiency. Our findings reveal that under various scales, biodiesel production from BSF larvae shows promise. For instance, in a small-scale urban biofuel plant, we estimate the production of approximately 122.73 liters of biodiesel per day from 1 ton of organic waste. Moreover, our calculations demonstrate the potential for medium-scale rural and large-scale industrial biofuel plants to produce 1,678.85 and 22,272.73 liters of biodiesel per day, respectively. These results highlight the significant biodiesel potential of BSF larvae. In conclusion, this study provides valuable insights into the biodiesel production potential of BSF larvae. It underscores the feasibility of utilizing organic waste for biodiesel production, contributing to sustainable biofuel development. Our research contributes to the knowledge base by offering quantitative assessments of biodiesel potential. We have incorporated quantitative data to provide a clearer understanding of the biodiesel potential and its economic implications.

Synergistic effect of selenium and gibberellic acid for enhanced biomass, lipid and improved biodiesel quality from Tetradesmus obliquus through response surface methodology

Biodiesel production from microalgae presents an innovative solution for renewable energy. This study investigates biodiesel production using Tetradesmus obliquus ON506010.1 by optimizing substrates, selenium and gibberellic acid. Using 15 µg/L selenium, lipid content and biomass productivity reached 35.45 %±0.92 and 0.178 g/L/day ± 0.051. With 50 µM gibberellic acid, biomass productivity and lipid content peaked at 0.785 ± 0.101 g/L/day and 38.95 %±0.35, surpassing the control. Fatty acid composition, biodiesel properties, and mRNA expression of lipid synthesis enzymes (acetyl CoA carboxylase (ACC) and fatty acid desaturase (FAD)) correlated. Combining 10 µg/L selenium with 75 µM gibberellic acid with response surface methodology (RSM) increased lipid content (42.80 % ±0.11) and biomass productivity (0.964 g/L/day ± 0.128). ACC and FAD upregulation validated this enhancement, with a 4.4-fold increase in FAD expression. Fatty acid composition and most biodiesel properties met international standards demonstrating Tetradesmus obliquus ON506010.1′s potential for sustainable biodiesel production with better cold flow property and oxidative stability.

A Spherical Superhydrophobic Activated Carbon Catalyst for Biodiesel Production ‐Exploring Process Efficiency, Kinetics, Thermodynamics and Life Cycle Cost Analysis

AbstractEngineering the wettability of functional materials holds significant interest, focusing on the need for superhydrophobic catalysts, crucial for their ability to prevent the poisoning of active sites by water, produced in situ or as a by‐product. Herein, for the first time, a superhydrophobic spherical activated carbon (SSAC@PhSO3H) is engineered as a catalyst via a novel synthetic approach and tailored in Jatropha curcas oil (JCO) biodiesel synthesis. With a large surface area (1461 m2 g−1), high acid density (6.26 mmol g−1), and water contact angle (163.4°), the catalyst demonstrates superior performance and remarkable water repellency, firmly establishing its superhydrophobic characteristics. Response Surface Methodology based on the Central Composite Design (RSM‐CCD) approach predicted a maximal biodiesel yield of 98.8% (80 °C, 5 wt%, 15:1 methanol to oil molar ratio (MOMR), and 40 min). Life cycle cost analysis (LCCA) estimates biodiesel production cost of 0.37 USD ($) per kg emphasizing high commercial viability. Compared with H2SO4‐sulfonated biochar, SSAC@PhSO3H retains its inherent activity (86.8 ± 0.4% yield in 10th run) and spherical morphology even after nine successive reaction cycles indicating high stability. Nevertheless, JCO biodiesel's fuel properties met European Norm, EN 14 212 and American Society for Testing and Materials, ASTM D6757 standards, highlighting its potential for industrial biodiesel production.

Efficient Preparation of Biodiesel Using Sulfonated Camellia oleifera Shell Biochar as a Catalyst.

This study prepared sulfonated Camellia oleifera shell biochar using Camellia oleifera shell agricultural waste as a carbon source, and evaluated its performance as a catalyst for preparing biodiesel. The biochar obtained from carbonizing Camellia oleifera shells at 500 °C for 2 h serves as the carbon skeleton, and then the biochar is sulfonated with chlorosulfonic acid. The sulfonic acid groups are mainly grafted onto the surface of Camellia oleifera shell biochar through covalent bonding to obtain sulfonic acid type biochar catalysts. The catalysts were characterized by Scanning Electron Microscope (SEM), X-ray diffraction (XRD), Nitrogen adsorption-desorption Brunel-Emmett-Taylor Theory (BET), and Fourier-transform infrared spectroscopy (FT-IR). The acid density of the sulfonated Camellia oleifera fruit shell biochar catalyst is 2.86 mmol/g, and the specific surface area is 2.67 m2/g, indicating high catalytic activity. The optimal reaction conditions are 4 wt% catalyst with a 6:1 alcohol to oil ratio. After esterification at 70 °C for 2 h, the yield of biodiesel was 91.4%. Under the optimal reaction conditions, after four repeated uses of the catalyst, the yield of biodiesel still reached 90%. Therefore, sulfonated Camellia oleifera shell biochar is a low-cost, green, non-homogeneous catalyst with great potential for biodiesel production by esterification reaction in future development.

Hybrid CaO/ZnFe2O4 Modified with Al2O3 as a Green Catalyst for Biodiesel Production from Waste Cooking Oil

In this work, biodiesel was produced from waste cooking oil (WCO) via a green catalyst of CaO-ZnFe2O4 modified Al2O3. The catalyst was characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-ray (EDX), SEM-mapping, Brunauer-Emmett-Teller (BET), transmission electron microscopy (TEM) analyses. The catalyst performance was studied in the transesterification reaction of WCO conversion to biodiesel. The catalytic activity increased with the combination of nanoparticles effect and support catalysts obtained biodiesel yield of nano-Al2O3, nano-CaO, ZnFe2O4, CaO-ZnFe2O4, and CaO-ZnFe2O4/Al2O3 is 36.86%, 67.16%, 74.83%, 86.54%, and 93.41%, respectively. The best biodiesel yield was 93.41% with a mass ratio of Al2O3 to CaO-ZnFe2O4 (2:1). The physicochemical properties (acid number, density, kinematic viscosity, flash point, and cetane number) of biodiesel under the optimal conditions agreed with the ASTM standard. These results show that the developed nanocomposite has great potential to reduce biodiesel production costs because derived from WCO. In conclusion, CaO-ZnFe2O4 modified Al2O3 as a catalyst has a high potential for biodiesel production on a large scale.

Biodiesel Production Potential from Oilseed Crops in Serbia

Biodiesel Production Potential from Oilseed Crops in Serbia

Phenotypic Characterization of Citron Watermelon (Citrullus lanatus var. citroides) Genotypes for Bioenergy Production

Citron watermelon (Citrullus lanatus var. citroides) is an important climate smart crop, characterized by high oil content in the seeds and it is a popular fruit in southern Africa. To determine best performing genotypes eight phenotypic traits were assessed to identify cultivars with potential for biodiesel production. A field experiment was conducted at Sebele Agricultural Research Station, in Southern Botswana, during 2019 to 2020 cropping season. Four (4) melon genotypes were planted in a Randomized Complete Block Design replicated three times and eight (8) characters were assessed. Except seed oil content (26.6%) there was significant (P < 0.05) difference among all the traits, an indication of higher genetic diversity in the selected citron watermelon. SC1-Sesoswane, exhibited highest seed yield (1540 kg/ha) and oil yield (435.03 kg/ha) while MMB-280-Lerotse recorded lowest seed yield and oil yield of 548.1 kg/ha and 144 kg/ha respectively. There was a significant correlation of (0.9) between oil yield (kg/ha), number of fruits produced, and seed yield (kg/ha), an indication that increasing the seed yield will positively increase the amount of oil produced. This study revealed the potential bioenergy production of the four cultivars. However, SC1-Sesoswane appears a more promising alternative cultivar for feedstock for biodiesel production.

Screening of efficient microalgae strains isolated from Tunisian ecosystems: Assessment of algal growth rate and added-value bioproducts for biorefinery applications

Microalgae are highly diverse organisms with significant applications in the production of high-value molecules and biodiesel from microalgae rich in oils. In this study, our main objectives were to evaluate the potential applications of four isolated microalgae strains, namely Scenedesmus sp., Nannochloris sp., Oscillatoria sp., and Amphora sp., which were selected from the natural environment. These strains were batch cultured, and their growth was monitored. We determined the content of chlorophyll a, carotenoids, and lipids, and analyzed the fatty acid profile of each cultivated strain to assess their lipid potential for biodiesel production. Our findings revealed that these strains exhibited high biomass production, ranging from 3000 mg. L−1 for Amphora sp. to 3800 mg. L−1 for Oscillatoria sp. Notably, Oscillatoria sp. and Scenedesmus sp. were found to be the richest in saturated fatty acids, with 10.68% and 9.36% of dry cell weight, respectively, suggesting their potential use in the production of biodiesel from microalgal oils with possibility of blending with other oils feedstock to improve biodiesel final quality. Furthermore, our results showed that the Nannochloris sp. strain could be cultivated to extract pigments for various applications, as it exhibited high levels of chlorophyll a (38.43 mg. L−1) and carotenoids (4.153 μg. mL−1).

Synthesis of HNTs-Ca/Zn catalyst for biodiesel production from acidulated palm oil: Optimized by GA-BP

The development of heterogeneous base catalyst with acid resistance has become a major topic in the current research on the biodiesel production process. Halloysite nanotubes (HNTs) is supported with bimetallic of calcium and zinc for modification and labeled as HNTs-Ca/Zn to show both the acid and base characteristics. Further, this supported catalyst is used to produce biodiesel from the acidulated palm oil through catalyzing transesterification in one-step in this study. The HNTs-Ca/Zn catalyst, synthesized by the impregnation method, is characterized by TG-DTG, XRD, XPS, TEM, SEM-EDX, nitrogen adsorption-desorption, CO2/NH3-TPD, FTIR and Raman. The capability of the HNTs-Ca/Zn catalyst in catalyzing transesterification is investigated, where the maximum yield of 95.22% is achieved with the molar ratio of Zn to Ca of 1.5. The advantage of HNTs-Ca/Zn1.5 catalyst is prominent when the transesterification source oil is acidulated, where the biodiesel yield of 92.66% is obtained even at the acid value of 26.02 mg KOH g−1. Besides, reusability of the catalyst is acceptable, where the yield of 77.91% is maintained after the fourth reused cycle. Further, the Genetic Algorithm-Back Propagation (GA-BP) neural network is used to train and predict the transesterification parameters of the reaction temperature, catalyst amount and methanol to oil molar ratio. The prediction of the biodiesel yield is reasonable. At the predicted reaction parameters of 158 °C, catalyst amount of 7.1 wt.% and methanol to oil molar ratio of 15.5, the predicted biodiesel yield is 98.71%, where the experimental verification value is 98.60%. Therefore, the HNTs-Ca/Zn catalyst is considered to demonstrate exceptional catalytic performance and recyclability, offering the potential for biodiesel production.

Nutrient and salinity stress induced biodiesel production from a green alga, Monoraphidium neglectum

The potential of a green alga as a versatile and sustainable feedstock for biodiesel production was assessed. Molecular identification revealed the alga to be Monoraphidium neglectum. Under diverse growth conditions, including nutrient deficiency and salinity stress, the microalga showed robust adaptability. Under nitrate deficiency (N-, the lipid content peaked (30.67 %), with a notable increase in monounsaturated fatty acids (MUFA), reaching 50.72 % in the stressed sample. Additionally, the highest polyunsaturated fatty acid (PUFA) content (24.55 %) was observed at a salinity level of 0.12 M. At 0.01 M salinity, the highest total carbohydrate content was observed. A significant fatty acid methyl ester (FAME) yield of 85.08 % was obtained under nitrate deficiency (N-) emphasizing its biodiesel production potential. The as-obtained biodiesel exhibited low viscosity, superior low-temperature performance and enhanced oxidation stability rendering the alga as an ideal candidate for eco-friendly, sustainable biodiesel production.

Lipid Yields and Fatty Acid Composition if Indigenous Microalgae, Isolated from the Beira, and Diyawanna Urban Lakes, for Sustainable Biofuel Production in Sri Lanka


 Biofuels are carbon-neutral combustibles produced from renewable biomass. Third generation biofuels, derived from microalgal biomass, are distinctly superior to their preceding generations, due to higher productivity and resource use efficiency of microalgae compared to conventional energy crops. It is a viable source of sustainable energy for our country due to the availability of water, ambient temperatures and year-round sunlight needed for microalgae cultivation, and most importantly, the abundance of diverse microalgae species. However, these native microalgae are relatively unexplored for their productivities and thereby, greatly underutilized. This research was aimed to investigate the lipid yields and fatty acid compositions of local freshwater microalgae, and to identify their potential for biodiesel production. This was carried out by (1) microalgae isolation and morphological identification (2) microalgae cultivation (3) biomass harvesting, lipid extraction, gravimetric measurement of extracted lipids and (4) acid-catalysed transesterification, followed by GCMS analysis of the biodiesel product. Chlorella sp., Chlorococcum sp. and Chlamydomonas sp. were isolated from Beira/ Diyawanna Lakes using streak plate technique in solid standard BBM media. They were next cultivated under axenic conditions in liquid standard BBM media under 16: 8 (light: dark), at 25°C for 20 days in duplicates. The biomass was then harvested using alum, dried to reach a constant weight and the Bligh and Dyer lipid extraction was done in triplicate. The extracted lipids were trans-esterified with methanol, using sulfuric acid catalyst at 90° C for 60 minutes. The separated product was analysed by GCMS. Chlorella sp., Chlorococcum sp. and Chlamydomonas sp. cultivated under standard conditions gave average lipid yields of 11.34±1.01%, 15.00±1.40% and 2.10±0.50% respectively. Average lipid yield of Chlamydomonas sp. was significantly lower than the other two species at 95% confidence level (Two-sample T test on SPSS Version 21). GCMS analysis of the biodiesel product from Chlorella sp. indicated significant levels of saturated fatty acids including palmitic and stearic acids, monounsaturated fatty acids like cis-11- eicosenoic acid and polyunsaturated fatty acids including linoleic and linolenic acids. The fatty acid ratios were used to calculate the saturation value, cetane number, density, iodine value and pour point of the produced biodiesel. These quality parameters were in accordance with the ASTM D6751- 20a standards. Therefore, with a substantial yield and fatty acid composition of intracellular lipids, this local species of Chlorella can be a prospective candidate for sustainable bioenergy production in Sri Lanka.
 
 Keywords: Chlorella, Chlorococcum, Chlamydomonas, Microalgal lipids, Biodiesel

Potential Application of Bacterial Lipase from Bacillus subtilis in the Production of Biodisel

This work aims to evaluate the potential of bacterial lipase of Bacillus subtilis in biodiesel production. Assays were performed to obtain, purify, and immobilize the enzyme and compare chemical and enzymatic transesterification tests. The Tryptic Soy Broth (TSB) culture medium without supplementation showed the highest enzymatic activity and purification yields when using 60% of (NH4)2SO4. Citral was the most efficient agent for lipase immobilization. Even though the free enzymes showed a higher activity rate, the immobilized enzymes are associated with a better-quality product. In conclusion, the lipase enzyme showed positive potential in biodiesel production.

Chemical Profiling and Industrial Viability of Neem Seed Oil: A Comprehensive Study for Sustainable Biodiesel Production

The study explores the chemical composition of neem seed oil, highlighting its potential for commercial biodiesel production and various industrial applications. The oil, with a liquid state, pale greenish-yellow color, and pleasant odor, yielded 32.1%, surpassing industrially extracted oils like soybean and cottonseed. Factors influencing its composition include seasonal variations, geographical origin, genetic disparities, growth stages, plant segments, and postharvest processing. Despite these, neem seeds meet the required oil content percentage for large-scale industrial biodiesel production. However, challenges like high free fatty acid content and elevated acid values necessitate acid esterification before alkaline transesterification, potentially increasing production costs. The study also highlights the importance of appropriate seed processing practices to optimize oil yield and quality.