Enhanced Biodiesel Production Research Articles

Enhanced biodiesel production from diseased swine fat by ultrasound-assisted two-step catalyzed process

In order to enhance the yield of high quality biodiesel form diseased swine fat, the ultrasound-assisted two-step catalyzed process was employed. First, three-dimensional ultrasound-assisted concentrated sulfuric acid pre-esterification experiment was carried out. Then, the transesterification reaction catalyzed by KOH was performed, and four parameters (catalyst concentration, reaction time, methanol/oil molar ratio and reaction temperature) were optimized using response surface methodology. The results showed that the optimal transesterification reaction conditions were catalyst concentration of 1.11 wt%, reaction temperature of 62.3 °C, methanol/oil molar ratio of 7.42:1, and reaction time of 116.14 min. The most significant factor affecting biodiesel purity was identified as catalyst concentration. Under the optimal conditions, the maximum biodiesel purity reached to 98% with the reaction time of 176.14 min, shortened by 63.3% compared with previous works. Furthermore, most of the biodiesel properties agreed the quality requirements established by Official Regulations of GB/25199-2017 of China.

Significant Seed Oil Feedstocks for Renewable Production of Biodiesel: A Review

: The rapidly increasing demand for biodiesel is now tying agriculture and energy more closely than ever. Biodiesel may be one of the key ways to pump immediate life into the flaccid economy of many underdeveloped countries. The present review critically describes leading potential feedstocks available for biodiesel production based on a full life-cycle analysis which comprises major producer countries, important cultivation practices and major fatty acid compositions of the produced biodiesel. This article provides a comprehensive approach about the twenty leading plant sources which can contribute to enhance biodiesel production throughout the world along with their production methodologies, physical and chemical fuel quality parameters and analytical techniques for the assessment of the quality of the prepared biodiesel. Biodiesel has become further interesting in recent years because of its eco-friendly benefits and the fact that it is made from renewable and sustainable resources. A wide literature review was conducted and the major fatty acid composition of various vegetable oils was discussed as it significantly affects biodiesel properties. Lipids obtained from filamentous fungi, for example, Cunninghamella echinulata exhibit great promise for biofuel production. Finally, this review will be helpful in promoting the development of biodiesel by several countries not only by extending scientific research and knowledge but also through the introduction of policies and expressing reasons underlying these policies. Conclusion: This review explains the potential feedstocks for renewable production of biodiesel.

Preparation and characterization of novel hybrid bio-support material immobilized from Pseudomonas cepacia lipase and its application to enhance biodiesel production

In the present study, hybrid bio-support catalyst (BSC) has been prepared for the production of biodiesel from Castor oil. Lipase from Pseudomonas cepacia has been immobilized on a hybrid bio-support material (BSM) by entrapment method and characterized. The highest immobilized lipase activity and loading efficiency were 87.28 (U/g) and 55.2%, respectively. The composition of Castor oil expelled from Castor seeds evaluated through Gas Chromatograph-Mass Spectrometer (GC-MS) technique. GCMS spectra show the percentage composition of ricinoleic, linoleic, oleic, stearic, palmitic, and nonanoic acid, as 78.67, 9.62, 6.65, 1.53, 2.19, and 0.08, respectively. Optimized conditions for the transesterification of Castor oil with propan-2-ol as acyl acceptor in solvent free medium were, 10% immobilized lipase relying on oil-weight, molar ratio of alcohol to oil (6:1) at 50±1°C for the period of 24 h. The product yield was estimated as 75% while the calculated conversion of biodiesel was approximately 78%. The reusability of hybrid BSC for 12 runs was found to be 70% of its initial biodiesel yield after 6 cycles. The properties of oil and biodiesel were calculated using American Standards for Testing Material (ASTM) D6751; formation of biodiesel confirmed by Proton Nuclear Magnetic Resonance (1H NMR) and Fourier Transform Infrared (FTIR) analysis.

Amelioration of biomass and lipid in marine alga by an endophytic fungus Piriformospora indica

BackgroundMany studies have been carried out on the growth-modulating efficiency of plants by the colonization of an endophytic fungus Piriformospora indica. However, studies involving the co-culture of alga with endophytic fungal strains for enhanced biodiesel production are rare. In this study, the interaction between P. indica and Parachlorella kessleri-I, a marine algal strain, was assessed at metabolic level.ResultsIn association with an endophytic fungus, the algal biomass enhanced from 471.6 to 704 mg/L, and the fatty acid methyl ester (FAME) profile of P. kessleri-I increased substantially. In case of FAME profile of co-cultured P. kessleri-I, two essential components of biodiesel, i.e. elaidic acid and oleic acid, increased by 1.4- and 1.8-fold, respectively. To ascertain changes in the metabolic profile of P. kessleri-I by P. indica co-culture, gas chromatography–mass spectrometry (GC–MS)-based untargeted metabolomics study was performed to identify the metabolites involved; and differential nature of the essential metabolites was also confirmed using HPLC and LC–MS. Significant modulation of the bioactive metabolites such as succinate, oxo-propanoate, l-alanine, glutamate, acetate and 1,2 propanediol, hydroxy butane was observed.ConclusionThe metabolites like glutamate and succinate that usually belong to the GABA shunt pathway were observed to be upregulated. The pathway links nitrogen metabolism and carbon metabolism, thus influencing the growth and lipid profile of the algae. These differential metabolites thus indicated the important commensal association between the endophytic fungus and autotrophic marine alga, and established that endophytic fungus can be handy for the sustainability of algal biofuel industries.

A two-stage model with nitrogen and silicon limitation enhances lipid productivity and biodiesel features of the marine bloom-forming diatom Skeletonema costatum

To enhance biodiesel production and quality from a bloom-forming diatom Skeletonema costatum, a two-stage model, in which cells were cultured in nutrient replete conditions first and then transferred to nutrient limitation conditions, was explored. Compared to one-stage model, nutrient limitation in the second stage significantly increased lipid content in spite of decreasing growth; consequently, Si-limitation and N-Si-limitation respectively increased lipid productivity by 37.6% and 76.7% for 6 h induction, and 42.8% and 113.7% for 12 induction. Nutrient limitation enhanced the proportions of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA) but reduced polyunsaturated fatty acid (PUFA). Therefore, N-Si-limitation reduced iodine value by 33.7% and 45.6% but increased cetane number by 6.4% and 21.6% for 6 and 24 h induction, respectively. These findings indicate that the two-stage model with N-Si-limitation can enhance lipid productivity as well as biodiesel quality from diatoms.

Fe3O4 nanoparticles impregnated eggshell as a novel catalyst for enhanced biodiesel production

Abstract Biodiesel is a green fuel which can replace diesel while addressing various issues such as scarcity of hydrocarbon fuels and environmental pollution to an extent. The high production cost of biodiesel and the recovery of the catalyst after the transesterification process are the major challenges to be addressed in biodiesel production. In the present work, a cheap and promising solid base oxide catalyst was synthesized from chicken eggshell by calcination at 900 °C forming catalyst eggshells (CES) and was impregnated with the nanomagnetic material (Fe3O4) to obtain Fe3O4 loaded catalytic eggshell (CES–Fe3O4). Fe3O4 nanomaterials were synthesized by co-precipitation method and were loaded in catalytic eggshell by sonication, for better recovery of the catalyst after transesterification process. CES–Fe3O4 material was characterized by Thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, a vibrating-sample magnetometer, Brunauer-Emmett-Teller, Dynamic light scattering, and Scanning electron microscopy. Biodiesel was synthesized by transesterification of Pongamia pinnata raw oil with 1:12 oil to methanol molar ratio and 2 wt% catalyst loading for 2 h at a temperature of 65 °C and yields were compared. The reusability of the catalyst was studied by the transesterification of the raw oil and its catalytic activity was found to be retained up to 7 cycles with a yield of 98%.

Ultrasound assisted oleaginous yeast lipid extraction and garbage lipase catalyzed transesterification for enhanced biodiesel production

While using microbial lipids as a biodiesel feedstock, effective extraction of lipids is essential. Also, the crude lipase produced from waste organics could be a potentially low-cost biocatalyst for the transesterification process. In this study ultrasound with the suitable solvent system was used for extracting the lipids from novel oleaginous yeast Naganishia liquefaciens NITTS2. Highest lipid recovery obtained was 99.3 ± 0.1% at optimized biomass concentration (60 g/L), solvents ratio (1: 1, chloroform/methanol), ultrasound power density (0.6 W/mL), 30 °C and 30 min. This lipid was characterized by GC-MS. It was then converted into biodiesel with garbage lipase as a catalyst using RSM designed transesterification process, which yielded 97.13 ± 1.05% at the optimum of 6.4 methanol/oil molar ratio, 20% enzyme concentration, 35 °C and 16 h. Thus, ultrasound aided extraction could be a promising method for lipid recovery from microbial biomass and the garbage lipase can be a sustainable, eco-friendly catalyst for commercial biodiesel production.

Techno-economic analysis of portable plant from waste cooking oil

Techno-economic analysis for portable biodiesel plant from waste cooking oil in Indonesia has been performed in this study. Analysis was performed by calculating the capital expenditures (CAPEX), operational expenditures (OPEX), and evaluation of economically aspects. Sensitivity of raw material cost, product price, and number of batch fluctuation have also been analyzed in this study. Overall process in this portable biodiesel plant has been simulated in the prior study and able to produce 128 L of biodiesel per batch production with 18 batch production per day. Based on calculation, the total of CAPEX and OPEX for this plant is IDR 5.354 billion and IDR 6.505 billion, respectively. Regarding to the economic evaluation, this plant will provide internal rate of return by 17.8%, net present value of IDR 7.196 billion, and payback period on the third year, with 20 years of plant lifetime with product price of USD 0.847/L. Hence, this plant is considered to be built and commercialized in order to enhance biodiesel production in Indonesia.

Enhanced biodiesel production from chicken fat using CaO/CuFe2O4 nanocatalyst and its combination with diesel to improve fuel properties

In this study, a new CaO/CuFe2O4 nanocatalyst was first synthesized and its structural and morphological properties were evaluated by using various analyzes such as SEM, FTIR, XRD, TGA, EDX and TEM. Then, biodiesel was prepared by using chicken fat in the presence of CaO/CuFe2O4 nanocatalyst during transesterification process. To determine the highest yield of biodiesel production, the effect of different parameters such as methanol to oil ratio (4:1–24:1), reaction time (0.5–6 h), reaction temperature (50–80 °C), and catalyst content (0.5–7%) was studied accordingly. The result indicated that the highest biodiesel yield was obtained at the methanol to oil ratio of 15:1, the reaction time of 4 h, the reaction temperature of 70 °C and catalyst content of 3% which was 94.52%. Subsequently, the biodiesel produced in optimum conditions was mixed with gasoline in various ratios (B100, B80, B60, B40, B30, B20 and B10). Finally, the physical and chemical properties of synthesis fuels such as density, flash point, kinematic viscosity, pour and cloud points were investigated based on the international standards of ASTM D 6751 and ASTM D 14214.

Effect of water content on [Bmim][HSO4] assisted in-situ transesterification of wet Nannochloropsis oceanica

1-Butyl-3-methylimidazolium hydrogen sulfate ([Bmim][HSO4]) was employed to catalyze the in-situ transesterification of wet Nannochloropsis oceanica. Algal cell wall was dissolved by [Bmim][HSO4] according to TEM analysis of untreated Nannochloropsis sp. cells and lipid extracted algae (LEA). The temperature and time are favorable to biodiesel production in 100–200 °C, time of 0–70 min, with methanol: algae, however, it decreased to 10.64% at time of 90 min. The biodiesel and energy production of [Bmim][HSO4] catalyzed in-situ transesterification varied due to the competition of catalytic property and algal dissolution ability with variation of water content. The catalytic property of [Bmim][HSO4] was the dominate parameter affecting biodiesel production, therefore, total energy production of in-situ transesterification, as a parameter of biodiesel production, was slightly increased from 13.12 kJ to 14.51KJ with water content of wet algae varied from 0 to 15 wt%. However, it decreased to 8.37 at water content of 20 wt% due to the weakened algal dissolution ability, which was proved by the decrease of hydrogen bond acceptor capacity(β) from 0.942858 to 0.942851 in water content of 0–30 wt%. The decomposition of carbohydrates and proteins in IL – water mixtures enhanced biodiesel production according to elemental analysis of LEA.

Biodiesel production from algae grown on food industry wastewater.

Algae have an ample potential to produce biodiesel from spent wash of food industry. In addition, it is cheaper and presents an environment friendly way to handle food industry wastewater. This study was conducted to optimize the growth of microalgal strains and to assess biodiesel production potential of algae using untreated food industry wastewater as a source of nutrients. The food industry wastewater was collected and analyzed for its physicochemical characteristics. Different dilutions (10, 20, 40, 80, and 100%) of this wastewater were made with distilled water, and growth of two microalgal strains (Cladophora sp. and Spyrogyra sp.) was recorded. Each type of wastewater was inoculated with microalgae, and biomass was harvested after 7days. The growth of both strains was also evaluated at varying temperatures, pH and light periods to optimize the algal growth for enhanced biodiesel production. After optimization, biodiesel production by Spyrogyra sp. was recorded in real food industry wastewater. The algal biomass increased with increasing level of food industry wastewater and was at maximum with 100% wastewater. Moreover, statistically similar results were found with algal growth on 100% wastewater and also on Bristol's media. The Cladophora sp. produced higher biomass than Spyrogyra sp. while growing on food industry wastewater. The optimal growth of both microalgal strains was observed at temperature 30°C, pH: 8, light 24h. Cladophora sp. was further evaluated for biodiesel production while growing on 100% wastewater and found that this strain produced high level of oil and biodiesel. Algae have an ample potential to produce biodiesel from spent wash of food industry. In addition, it is cheaper and presents an environment friendly way to handle food industry wastewater.

Experimental validation of biochar based green Bronsted acid catalysts for simultaneous esterification and transesterification in biodiesel production

In this study, a variety of novel biochar based Bronsted acid catalysts were prepared from low cost potential feedstocks viz., cassava peel, irul sawdust, coconut shell and their catalytic activity for biodiesel production were compared. The optimization studies of biochar generation were carried out based on the influence of pyrolysis temperature and heating duration, for the preparation of acid catalyst with superior activity. The elemental analysis, surface functional groups, thermal stability, crystallographic structure, surface morphology and pore size distribution of all biochars and its sulfonated catalysts were characterized thoroughly. The performance of the sulfonated biochar catalysts for the synthesis of biodiesel from Derris indica L. seed oil was evaluated and compared. The cassava peel biochar based catalyst with a total acid density of 2.9 mmol/g and sulfonic acid group density of 1.7 mmol/g showed the best result among the sulfonated biochar catalysts for the enhanced biodiesel production.

Utilization of de-oiled algal biomass for enhancing vehicular quality biodiesel production from Chlorella sp. in mixotrophic cultivation systems

Abstract The investigation first time reports the efficacy of de-oiled algal biomass extract (DOABE) for mixotrophic cultivation of Chlorella sp. MCC27 to enhance biodiesel production in open tray systems and in BioXpert-V2 software connected photobioreactor (PBR). The cultivation systems with addition of DOABE (PBR systems + DOABE and open tray system + DOABE) as media were tested for quality and quantity of biodiesel. The presence of organic carbon and low nitrogen in DOABE caused >2 folds higher biomass productivity and >4 folds enhanced lipid productivity for the cells cultivated in PBR system + DOABE and open tray system + DOABE as compared to control (i.e. BBM). Biochemical analysis of cells from both the systems revealed the decrease in total carbohydrates and protein contents. The FAMEs analyses showed vehicular quality biodiesel. PBR system + DOABE showed edge over open tray system + DOABE in terms of biomass productivity and lipid content. The physical properties of biodiesel produced from Chlorella sp. MCC27 were more close to the fuel standards (ASTM D6751), when cells were cultivated in open tray system + DOABE than in PBR system + DOABE. Collectively, this study highlights the use of DOABE as a low cost feedstock for enhancing vehicular quality biodiesel production from microalgae.

Effect of lipid-free microalgal biomass and waste glycerol on growth and lipid production of Scenedesmus obliquus: Innovative waste recycling for extraordinary lipid production

In the present work, a novel approach of using growth medium with different substitutions of lipid-free algal hydrolysate (LFAH, 0, 5, 10 and 15%) and/or waste glycerol (WG, 0, 5, 10 and 20 g L−1) for enhanced biodiesel production from Scenedesmus obliquus was studied. Combination of different concentrations of WG with 15% LFAH showed the maximum significant biomass productivity, which represented 27.4, 30.5 and 28.9% over the control at combined 5, 10 and 20 g L−1 WG, respectively. The combinations of different LFAH with 20 g L−1 WG showed the maximum significant lipid accumulation, where lipid productivity showed its maximum significant value of 59.66 mg L−1 d−1 using LFAH15-WG10. In addition, LFAH15-WG10 significantly enhanced total FAMEs yield by 21.2% over the control. Moreover, it reduced polyunsaturated fatty acids (PUFAs) ratio from 52.1% to 47.8% of total FAMEs, and increased monounsaturated fatty acids (MUFAs) ratio from 26.6% to 31.3% of total FAMEs.

Use of high-throughput techniques to study simultaneous production of lipid metabolites in carotenogenic yeasts grown on waste animal fat

This study focuses on the valorisation of crude glycerol and sunflower meal (SFM) from conventional biodiesel production plants for the separation of value-added co-products (antioxidant-rich extracts and protein isolate) and for enhancing biodiesel production through microbial oil synthesis. Microbial oil production was evaluated using three oleaginous yeast strains (Rhodosporidium toruloides, Lipomyces starkeyi and Cryptococcus curvatus) cultivated on crude glycerol and nutrient-rich hydrolysates derived from either whole SFM or SFM fractions that remained after separation of value-added co-products. Fed-batch bioreactor cultures with R. toruloides led to the production of 37.4 g L−1 of total dry weight with a microbial oil content of 51.3% (w w−1) when a biorefinery concept based on SFM fractionation was employed. The estimated biodiesel properties conformed with the limits set by the EN 14214 and ASTM D 6751 standards. The estimated cold filter plugging point (7.3–8.6 °C) of the lipids produced by R. toruloides is closer to that of biodiesel derived from palm oil.

Excessive phosphorus enhances Chlorella regularis lipid production under nitrogen starvation stress during glucose heterotrophic cultivation

Recent studies claimed nitrogen starvation in addition to sufficient phosphorus content to be a “lipid trigger” for microalgae autotrophic cultivation. However, the role of phosphorus in heterotrophic cultivation still remains controversial. Here, we investigated the utilization of a series of phosphorus concentrations of up to 818% in BG11 medium to cultivate Chlorella regularis under nitrogen starvation stress during glucose heterotrophic cultivation. Phosphorus positively influenced microalgal cell synthesis, and the lipid content increased with increasing levels of supplied phosphorus. The excess phosphorus was stored in the form of Poly-P, thus providing energy and participating in the synthesis of cellular materials, which enhanced cell growth and lipid accumulation. The biomass production reached 4.53g/L under nitrogen starvation with excess phosphorus supply, which was comparable to the effect of a nitrogen-sufficient condition (control). The excessive phosphorus level upregulated the genes ROT3, BAS1, CYP735A, FBP, GOT2, and AOC3 associated with growth. Microalgal lipid content reached 42.3% and lipid productivity reached 310.0mg/(L·d), values that were 2 and 1.3times higher than those in the control, respectively. Furthermore, the additional phosphorus supply increased the amounts of saturated fatty acids, while shifting fatty acid pathways. We suggest that higher amounts of phosphorus should be supplied to achieve high microalgal lipid productivity under nitrogen starvation stress during glucose heterotrophic cultivation. This is an effective strategy to enhance biodiesel production, simultaneously achieving high biomass production and efficient lipid accumulation.

Heterotrophic cultivation of microalgae in photobioreactor using low cost crude glycerol for enhanced biodiesel production

This integrated approach first time investigates the use of crude glycerol (CG), a primary by product of the biodiesel production, for heterotrophic cultivation of microalgae (namely, Chlorella sp.) in photobioreactor (PBR) to enhance biodiesel production. The glycerol was reported 28.5 ± 0.70% in CG, causing nearly two folds increase in biomass productivity (446.50 ± 1.50 mg L−1day−1) and nearly four folds enhanced lipid productivity (165.15 ± 0.55 mg L−1 day−1) for the algal cells cultivated in PBR with addition of CG (PBR+CG) system as compared to Bold's Basal media (BBM) used as control. The total lipid content (34.36 ± 0.51%) was also doubled for the cells grown in PBR+CG system than in BBM. The analysis of fatty acid methyl esters (FAMEs) profile by GC-MS showed reduction in total unsaturated fatty acids and poly unsaturated fatty acids, and increase in total saturated fatty acids (SFAs) for the biodiesel obtained from algal cells grown in PBR+CG system. Moreover, the physical properties estimation also specified higher cetane number (53.89) and average oxidative stability (3.41 h), which are comparable with ASTM D6751 and EN 14214 fuel standards. This study demonstrates the potential of the use of CG for enhancing the low cost biodiesel production for vehicular transportation.

Enhanced biodiesel production through phyco-myco co-cultivation of Chlorella minutissima and Aspergillus awamori: An integrated approach

Algae-fungus co-culture was investigated as an alternative biodiesel feedstock. An oleaginous filamentous fungus Aspergillus awamori was co-cultured with Chlorella minutissima MCC 27 and Chlorella minutissima UTEX 2219, respectively in N11 medium furnished with different carbon and nitrogen sources. The biomass and lipid production potential of the two C. minutissima–A. awamori co-cultures was compared against the monocultures. A substantial enhancement in biomass and lipid accumulation was observed in both the co-cultures. When supplemented with different carbon and nitrogen sources, glycerol and potassium nitrate were found to be the most effective. In the presence of glycerol, a 2.6–3.9-fold increase of biomass and 3.4–5.1-fold increase of total lipid yields were observed in the co-cultures as compared to the axenic monocultures. Furthermore, C16:0 (31.26–35.02%) and C18:1 (21.14–24.21%) fatty acids were the major composites of the co-culture oils, which suggest co-culture as a promising strategy for biodiesel production.

Augmented lipid accumulation in ethyl methyl sulphonate mutants of oleaginous microalga for biodiesel production

The aim of this work was to generate high lipid accumulating mutants of Chlorella minutissima (CM) using ethyl methyl sulphonate (EMS) as a random chemical mutagen. Amid the 5% surviving cells after exposure to EMS (2M), three fast growing mutants (CM2, CM5, CM7) were selected and compared with wild type for lipid productivity and biochemical composition. Among these mutants, CM7 showed the maximum biomass (2.4g/L) and lipid content (42%) as compared to wild type (1.5g/L; 27%). Further, the mutant showed high photosynthetic pigments with low starch content signifying the re-allocation of carbon flux to lipid. The obtained mutant showed no visible morphological changes in comparison to its WT. The fatty acid profile showed increase in monounsaturated fatty acids while decreased saturated and polyunsaturated fatty acids signifying good quality biodiesel. The mutant strain thus obtained can be optimized further and applied for enhanced biodiesel production.

Efficient solvothermal wet in situ transesterification of Nannochloropsis gaditana for biodiesel production.

In situ transesterification of wet microalgae is a promising, simplified alternative biodiesel production process that replaces multiple operations of cell drying, extraction, and transesterification reaction. This study addresses enhanced biodiesel production from Nannochloropsis gaditana at elevated temperatures. Compared with the previously reported in situ transesterification process of conducting the reaction at a temperature ranging from 95 to 125 °C, the present work employs higher temperatures of at least 150 °C. This relatively harsh condition allows much less acid catalyst with or without co-solvent to be used during this single extraction-conversion process. Without any co-solvent, 0.58% (v/v) of H2SO4 in the reaction medium can achieve 90wt% of the total lipid conversion to biodiesel at 170 °C when the moisture content of wet algal paste is 80wt%. Here, the effects of temperature, acid catalyst, and co-solvent on the FAEE yield and specification were scrutinized, and the reaction kinetic was investigated to understand the solvothermal in situ transesterification reaction at the high temperature. Having a biphasic system (water/chloroform) during the reaction also helped to meet biodiesel quality standard EN 14214, as Na+, K+, Ca2+, Mg2+ cations and phosphorus were detected only below 5ppm. With highlights on the economic feasibility, wet in situ transesterification at the high temperature can contribute to sustainable production of biodiesel from microalgae by reducing the chemical input and relieve the burden of extensive post purification process, therefore a step towards green process.