Maximum Fatty Acid Methyl Ester Research Articles

Potential of algal oil production from secondary treated sewage: a study using Chlorella vulgaris and synthetic wastewater

ABSTRACTTo assess the potential of using the secondary treated wastewater for the production of algal biofuel, batch experiments were carried out in photobioreactors using indigenous Chlorella vulgaris isolated from the natural freshwater body. Secondary treated wastewater with partial nitrification was simulated using various proportions of NO3-N and NH4-N while keeping the total nitrogen the same. Experiments with similar concentrations of nitrate without the NH4-N were used for comparison. In the presence of only NO3-N in the concentration range of 9–37 mg/L, the growth and fatty acid methyl ester (FAME) production was similar to the literature reports. When NH4-N was present along with NO3-N, the biomass growth was adversely affected, indicating an impact on the metabolic activity. For the same initial concentrations of nitrate in the culture, the maximum biomass concentration was reduced by 50–60% in the presence of NH4-N. The FAME profile changed significantly and a new FAME was identified, suggesting an impact on the lipid synthesis pathway. Comparison and analysis with the help of existing literature indicated that the adverse effect due to NH4-N was a function of pH. The growth, biomass yield, and FAME production were unaffected by a wide range of phosphorus concentrations. Maximum fatty acid methyl ester (FAME) suitable for biodiesel production (fatty acid carbon chain length C16 to C18) was 381.01 mg/L (224.58 mg/g of dry biomass), produced at NO3-N concentration of 18.5 mg/L and initial nitrogen loading per unit biomass of 0.37 g NO3-N/g of dry biomass.

Strategy for lipid extraction and transesterification to enhance Chlorella sorokiniana strain BV 12 feedstock utilization

Efficient production and recovery of fatty acid methyl esters (FAMEs) from lipid containing feedstock is the key step of biodiesel production. This enhances the utilization of feedstock and improves the final economics of the process. Currently, direct and indirect transesterification strategies are being employed for biodiesel production from microalgae with few reports of tailoring the process to a specific feedstock. In this study, Chlorella sorokiniana strain BV 12 was grown in modified BG-11 medium and biomass was harvested. This was subjected to different physical, chemical and physico-chemical strategies for increasing the transesterification yield. The transesterified lipid was evaluated for various biodiesel properties like iodine value, saponification value, acid value, peroxide value and cetane number. After harvesting, gravimetric lipid yield of 161.7 mg/g and 4117.5 µg/g of FAME were obtained. Extraction of lipid was dependent on the cell disruption technique as it is accumulated intracellularly as droplets. Sonication resulted in maximum FAME production using either dry (4724.2 µg/g) and wet (4835.8 µg/g) biomass which shows that wet biomass is more suitable for processing. Gravimetric results favour the extraction by sonication showing a 63.22% increase in lipid recovery. Testing of different solvents for extraction showed methanol as most favourable for FAME analysis with acidic catalyst like HCl and H2SO4 giving FAME with better ignition value (∼51, Cetane number).

Revolutionizing biodiesel production: A breakthrough synthesis and characterization of bismuth ferrite nanocatalysts for transesterification of palm and waste cooking oil

The present work deals with the successful synthesis of heterogeneous bismuth ferrite nanocatalysts (BiFeO3) using kappa-carrageenan polysaccharides to study the efficient transesterification of palm cooking oil for biodiesel production. The optimized size of pristine BiFeO3 obtained was 95.8 nm, at a molar ratio of (Bi: Fe; 1:2) with a 1 % carrageenan biotemplate and calcined at 823 K for 2 h. The nanocatalysts have been producing high thermal stability, and X-ray diffraction (XRD) analysis showed the rhombohedral crystalline phases. The BiFeO3 nanocatalysts demonstrated outstanding catalytic performance during the transesterification of palm and waste cooking oils. The abovementioned processes with different reaction parameters for the production of fatty acid methyl ester (FAME) were investigated in batches. The effects of the catalyst dosage, temperature, time, and molar ratio (oil/methanol) have been conducted. A maximum FAME yield of 98% was achieved using optimized conditions: oil and methanol at a molar ratio of 1:15, and BiFeO3 with a 7 wt% catalyst dosage in 2 h at 353 K. The results indicated high chemical stability of the catalyst after five consecutive cycles with the same catalytic performance and proved to be a suitable catalyst for the production of biodiesel with high reaction rates and low catalyst usage.

Synthesis and Characterization of Physically Mixed V2O5.CaO as Bifunctional Catalyst for Methyl Ester Production from Waste Cooking Oil

Synthesis of the solid bifunctional vanadium-calcium mixed oxides catalyst was accomplished by application of a simple physical mixing approach. In this work, we compared the catalytic activity of CaO and 2%V2O5.CaO catalyst. Various characterization methods, such as X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR), BET surface area, and temperature-programmed desorption (TPD) of CO2 and NH3, were involved in studying the newly synthesized catalysts. The presence of CaO, CaCO3, and Ca(OH)2 compounds in the synthesized catalyst were detected by XRD and FTIR analysis. The existence of 2% V2O5 on the CaO catalyst surface was demonstrated by XRF analysis. From TPD-NH3, TPD-CO2, and BET surface area analysis, it was known that the 2% V2O5-CaO catalyst had a higher total number of acid-base sites and surface area than the CaO catalyst. In the fatty acid methyl esters (FAME) production from waste cooking oil (WCO) with higher free fatty acid (FFA), CaO could only catalyze the transesterification reaction. In contrast, 2%V2O5-CaO could successfully catalyze both the esterification of FFA and the transesterification of triglyceride (TG) simultaneously in a one-step reaction process. Thus, these results prove that 2%V2O5.CaO can act as a bifunctional catalyst in the production of biodiesel from WCO. Moreover, the synthesized 2%V2O5.CaO catalyst could achieve a maximum FAME yield of 51.30% under mild reaction conditions, including a 20:1 methanol to oil molar ratio, 60 °C reaction temperature, 1 wt% of catalyst loading, and 3 hours of reaction time.

Intensification of interesterification of sustainable feedstock as mahua oil for biodiesel production

ABSTRACT In the current work, the ultrasonic horn induced cavitation was used as an intensification approach for the production of fatty acid methyl esters (FAME), i.e. biodiesel and triacetin as a by-product from the reaction of mahua oil selected as sustainable feedstock and methyl acetate (MA). The effects of process variables like reaction temperature, mahua oil to methyl acetate molar ratio, reaction time, catalyst loading, duty cycle, and power on yield of FAME have been studied and the results elucidated best conditions for maximum fatty acid methyl ester yield of 96% as time of 50 min, temperature of 50C, molar ratio of 1:8, duty cycle of 40%, ultrasonic power of 70 W and catalyst loading of 1 wt%. For conventional approach based on only stirring, the yield was 61% under otherwise similar conditions. Kinetic study was performed to estimate the order of reaction and the activation energy. It was shown that the kinetics was well fitted to first-order reaction and activation energy was observed as 25.9 kJ/mol. The study revealed the effective application of ultrasonic horn in intensification of biodiesel production using interesterification reaction resulting in considerably higher yield of FAME.

Reactive Extraction for Fatty Acid Methyl Ester Production from Castor Seeds Using a Heterogeneous Base Catalyst: Process Parameter Optimization and Characterization

Fatty acid methyl ester (FAME) from oil seeds is conventionally produced via a two/three-process-step method: extraction of oil and subsequent esterification/transesterification to fatty FAME (biodiesel). However, in the present study, we investigated the production of castor kernel oil (CKO) FAME by reactive extraction for extraction and transesterification in a single process using a heterogeneous catalyst. The content of oil that can be extracted was checked by investigating several nonreactive extraction parameters such as solvent type (polar, nonpolar, and mixture), the solvent to kernel ratio, and extraction time. Maximum oil was extracted using methanol as a solvent with a methanol-to-seed ratio of 6.25:1 for 6 h extraction time. The viscosity of CKO obtained by nonreactive extraction was reduced from 288.83 to 19.04 mm2/s by reactive extraction using a 4.09 wt % catalyst concentration (BaO) and a 330.9:1 methanol-to-oil molar ratio for 6 h reaction time at 64 °C. Reactive extraction for transesterification of CKO was performed using BaO, CaO, and ZnO heterogeneous catalysts. BaO results in the increased yield of CKO FAME compared to other catalysts. Central composite design (CCD) using the response surface methodology (RSM) was implemented to design the experimental matrix, process parameter optimization, maximize the yield of CKO FAME, and investigate interaction effects of parameters such as reactive extraction temperature (55-65 °C), catalyst concentration (3-5 wt %), and methanol-to-oil molar ratio (175:1-350:1) on the yield of CKO FAME. A second-order model equation with a p-value < 0.05 and an R 2 value near 1.0 was obtained to predict the yield using the input parameters. The maximum yield CKO FAME of 96.13 wt % with 94.4% purity of produced CKO FAME was obtained at a catalyst concentration of 4.09 wt % and a methanol-to-oil molar ratio of 330.9:1 for 6 h with a reaction temperature of 64 °C. Therefore, a comparable conversion of castor seed oil triglyceride (96.13 wt %) was obtained in a single step directly from castor seeds. Furthermore, the rheological behavior investigation of castor kernel oil and castor methyl ester revealed that the dynamic viscosity of both samples was found to be dependent on triglyceride content and temperature.

Study the Stable Diatomite-supported Catalyst for Biodiesel Production

The stable of natural diatomite supported by potassium hydroxide (KOH) as catalysts were synthesized for biodiesel production. A heterogeneous base catalyst prepared by impregnating KOH onto diatomite was also used to synthesize biodiesel from palm oil. All samples have been thoroughly characterized by Wavelength Dispersive X-ray Fluorescence (WDXRF), X-ray diffraction (XRD), N2 adsorption/desorption, Scanning electron microscopy (SEM), Energy dispersive spectrometer (EDS), and Temperature-programmed desorption of carbon dioxide (CO2-TPD). The XRD, XRF, and SEM results confi rm that adding KOH to diatomite results in structural change. The SiO2 and K2O phases form in the diatomite structural matrix during impregnation and the total basicity amount of this compound promotes the transesterifi cation process. A maximum fatty acid methyl ester (FAME) content of 84.56% was obtained. The reaction conditions were as follows: molar ratio of oil to methanol 1:9, catalyst loading 5 wt%, reaction time 2 h, and reaction temperature 75 °C. This work provides a possible new method for converting KOH from a homogeneous to a heterogeneous catalyst (Diatomite/KOH) that may show stable reusability, avoiding the separation and pollution problems in the environment.

High-Level Production of Recombinant Lipase by Fed-Batch Fermentation in Escherichia coli and Its Application in Biodiesel Synthesis from Waste Cooking Oils.

The enzymatic production of biodiesel from waste cooking oils (WCOs) offers a green and sustainable solution for the liquid fuel manufacture as well as waste resource recovery. In present study, liquid lipase was used to simplify the catalysis process, thereby reducing biodiesel production costs. An engineered Escherichia coli expressing Geobacillus thermocatenulatus lipase 2 (GTL2) was screened at an enzyme activity of 6.96 U/mg, after evaluating the propagating stability of the recombinant plasmids exceeding 86.11%. Through the beneficial feeding strategy and effective pH control, high-level production of GTL2 by fed-batch fermentation was achieved with an enzyme activity of 434.32 U/mg, which was almost 62 times that of shake flask fermentation. In addition, liquid GTL2 was used to prepare fatty acid methyl esters (FAMEs) using WCOs. The effects of the reaction time, catalyst loading, temperature, and methanol-to-oil molar ratio on FAMEs production using WCOs were explored, and a maximum FAMEs yield of 96.62% was achieved under optimized conditions. These results indicate that liquid GTL2 is a promising biocatalyst for efficient utilization of WCOs in the synthesis of biodiesel and provide a novel enzymatic process for biodiesel reducing the cost of production.

Development of a zeolite supported CaO derived from chicken eggshell as active base catalyst for used cooking oil biodiesel production

Herein, used cooking oil (UCO) was upgraded to fatty acid methyl ester (FAME) via methanolysis process using zeolite based eggshell (ZE/ES) composite catalyst. The ZE/ES catalyst was prepared using wet impregnation technique followed by calcination at different temperatures (700–900 °C), and its properties were evaluated by various characterization techniques (BET, TGA/DTA, FTIR, CO2-TPD, XRD, SEM and surface basicity). Optimization of methanolysis of UCO was studied using central composite design. Under the optimum transesterification conditions (at 69.1 °C for 238.8 min using methanol/UCO molar ratio of 9.7:1 with 2.1 wt% catalyst dosage), the maximum FAME content was 93.7% when composite catalyst synthesized by loading 2 g of zeolite with 5 g of eggshell and calcined at 800 °C (2ZE/ES-800) was utilized. The remarkable performance of 2ZE/ES-800 could be attributed to its high basic strength (1181.1 μ mol/g) and dominance of the CaO on its surface. Reusability study showed that the 2ZE/ES-800 catalyst could be reused for five successive cycles with no significant decrease in catalyst activity.

Response surface methodology for continuous biodiesel production from Jatropha curcas oil using Li/pumice as catalyst in a packed-bed reactor assisted with diethyl ether as cosolvent

A packed-bed catalytic configuration reactor using pumice granules loaded with lithium (Li/Pumice) as a heterogeneous catalyst was developed for biodiesel production in continuous. For this purpose, Jatropha curcas oil was used as an alternative feedstock to edible oils and diethyl ether was used as a cosolvent to eliminate the limitations of mass transfer between the phases. In this work, the response surface methodology was applied to optimize the fatty acid methyl esters (FAME) yield in biodiesel production. The flow rate (0.7–1.4 mL min−1), the methanol/oil molar ratio (6:1–20:1) and the cosolvent/methanol molar ratio (0.5:1–1.5:1) were the independent variables studied. The effects of these factors over the FAME yield using Li/Pumice as catalyst were evaluated according to a Box-Behnken design. The optimum conditions for the maximum FAME yield (100%) were 1.4 mL min−1, 20.0 methanol/oil molar ratio and 0.57:1 cosolvent/methanol molar ratio.

Light Stress after Heterotrophic Cultivation Enhances Lutein and Biofuel Production from a Novel Algal Strain Scenedesmus obliquus ABC-009.

Scenedesmus obliquus ABC-009 is a microalgal strain that accumulates large amounts of lutein, particularly when subjected to growth-limiting conditions. Here, the performance of this strain was evaluated for the simultaneous production of lutein and biofuels under three different modes of cultivation - photoautotrophic mode using BG-11 medium with air or 2% CO2 and heterotrophic mode using YM medium. While it was found that the highest fatty acid methyl ester (FAME) level and lutein content per biomass (%) were achieved in BG-11 medium with CO2 and air, respectively, heterotrophic cultivation resulted in much higher biomass productivity. While the cell concentrations of the cultures grown under BG-11 and CO2 were largely similar to those grown in YM medium, the disparity in the biomass yield was largely attributed to the larger cell volume in heterotrophically cultivated cells. Post-cultivation light treatment was found to further enhance the biomass productivity in all three cases and lutein content in heterotrophic conditions. Consequently, the maximum biomass (757.14 ± 20.20 mg/l/d), FAME (92.78 ± 0.08 mg/l/d), and lutein (1.006 ± 0.23 mg/l/d) productivities were obtained under heterotrophic cultivation. Next, large-scale lutein production using microalgae was demonstrated using a 1-ton open raceway pond cultivation system and a low-cost fertilizer (Eco-Sol). The overall biomass yields were similar in both media, while slightly higher lutein content was obtained using the fertilizer owing to the higher nitrogen content.

Optimization of Biodiesel Production from Sunflower Oil Transesterification using Ca-K/Al2O3 Nanocatalysts

In this study, an attempt was made to optimize the conditions for the transesterification of sunflower oil with methanol, catalyzed by Ca-K/Al2O3 nanocatalysts, using response surface methodology. The examined variables were reaction temperature (55, 65 and 75 °C), reaction time (1, 2, 3, 4 and 5 h), catalyst weight base oil (3, 6, 9 and 12 wt%), Ca content (20, 30, 50, 60 and 80 wt%), K content (5, 10, 15 and 20), methanol:sunflower oil molar ratio (3:1, 6:1, 9:1 and 12:1), calcination temperature (600, 700 and 800 °C) and calcination time (1, 2, 3 and 4 h). Catalyst characterization was done by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR) and temperature programmed desorption (TPD). The maximum fatty acid methyl esters (FAME) conversion efficiency (biodiesel production efficiency) was 98.3%, at a calcination temperature of 800 °C for 3 h, a methanol-to-oil ratio of 9:1, a reaction temperature of 75 °C, a reaction time of 3 h and a catalyst-to-oil mass ratio of 9%.

Optimization of the real conversion efficiency of waste cooking oil to fame

This work presents a polynomial regression model for the optimization of the content of fatty acid methyl esters and the conversion yield of waste vegetable oil to biodiesel. The equations are optimized to obtain the maximum fatty acid methyl esters yield, which is the product of the conversion yield and the fatty acid methyl esters content in the biodiesel. The independent variables considered are the type of catalyst used (KOH and NaOH), percentage of catalyst (0.6%, 1.0%, and 1.5% w/w with respect to oil), and the methanol: oil molar ratio (6:1, 7.5:1, and 9:1). The prediction models are obtained by using nine experimental points for each catalyst. The validation is developed with four main experimental points from the mapping. A polynomial relation is obtained as a consequence, which correlates each of the experimental variables with the fatty acid methyl esters and conversion yield. The optimization of the proposed models shows an error of 2.66% for the fatty acid methyl esters, and an error of less than 1% for the conversion yield are obtained. This work presents a straight forward methodology to obtain the best chemical conditions in the production of biodiesel by using a small number of experiments, obtaining good results. This methodology can be applied for biodiesel production from any raw material, recalculating each of the regression constants thus allowing to obtain the highest quantity of oil to be converted in fatty acid methyl esters.

Systematic production of biodiesel fuel from palm oil over porous K2O@CaO catalyst derived from waste chicken eggshell via RSM/kinetic/thermodynamic studies

Sustainable synthesis of biodiesel fuel or fatty acid methyl ester (FAME) was studied via transesterification of palm oil (PO) over green/low-cost heterogeneous alkali (waste chicken eggshell/WCE) catalyst. The porous K2O@CaO catalyst was effectively prepared via one-pot hydration-dehydration-incorporation process. The following reformations of catalyst properties were characterized by BET, XRD, SEM-EDX, TGA, FT-IR and CO2-TPD techniques. As obtained results, the as-modified catalysts with characteristic properties such as stronger basic site, higher basicity and surface area were successfully achieved when compared with pristine/commercial CaO, resulting in more facile upgrading of PO to FAME product. An integration between 2k factorial process with Box-Behnken model found that significant factors was in the order of catalyst loading amount > reaction time > reaction temperature. Meanwhile, the obtained optimal conditions were catalyst loading amount = 3 wt% of oil, molar ratio of methanol to oil = 15:1, reaction temperature = 80 °C and reaction temperature = 2 h, imparting a maximum FAME yield of 87.5%. For kinetic and thermodynamic studies of 10%KI/CaO catalyzed transesterification of PO, the important parameters such as Ea, A, ΔH, ΔS and ΔG were found to be 40.04 kJ/mol, 2.85 × 102 min−1, 37.24 kJ/mol, − 172.61 J/mol.K and 60.97 kJ/mol, respectively. The calcium glyceroxide was easily formed during reusability test, resulting in a significant reduction of FAME yield. Thus, regeneration-calcination process at 800 °C was applied to fully recover its properties and catalytic performance. This work provided the eco-friendly strategy for FAME production which could be possibly applied in practical process.

Valorization of de-oiled microalgal biomass as a carbon-based heterogeneous catalyst for a sustainable biodiesel production

In this study, a novel carbon-based solid acid catalyst was synthesized by carbonization of de-oiled microalgal biomass followed by sulfonation. The effect of catalyst synthesis conditions such as carbonization temperature, sulfonation time, and H2SO4 concentration on the surface acidity of the catalyst and free fatty acid conversion was determined. The de-oiled microalgal biomass-based solid acid (DMB) catalyst was predominantly composed of carboxylic, phenolic, and sulfonic groups as indicated by the FTIR analysis and supported by the XPS analysis. The catalyst was further characterized by various methods to determine its physiochemical properties. A maximum fatty acid methyl ester (FAME) yield of 94.23% for microalgal oil (AO) and 96.25% for waste cooking oil (WCO) was obtained under optimized transesterification conditions. The catalyst exhibited high catalytic activity (FAME yield >90%) until the fourth cycle. Most of the biodiesel properties were within the permissible limit of EN 14,212 and ASTM D6751 standards.

Optimization of flamboyant-based catalysts functionalized with calcium for fatty acid methyl esters production via transesterification

Solid catalysts were prepared from flamboyant pods via pyrolysis with a subsequent surface chemistry functionalization using calcium nitrate. These catalysts were assessed in the transesterification of safflower oil as a model reaction to obtain fatty acid methyl esters (FAMEs). The catalyst preparation route was studied and optimized using a Taguchi experimental design, where the best synthesis conditions were determined to maximize FAMEs formation. Physicochemical characterization of catalysts was performed to analyze the impact of their preparation conditions on FAMEs formation. Results showed that a maximum FAMEs formation of 93% was obtained with the optimized catalyst preparation conditions. Pseudo-first order kinetic model fitted the experimental data of FAMEs from transesterification, which was endothermic and chemically controlled. Recovery and recycling experiments showed that the performance of this catalyst was competitive with a thermal reactivation up to three cycles where the calcium leaching was also minimum. These results contribute with an alternative, low cost and green route for the preparation of catalysts for FAMEs production, which can be used as fuels or feedstocks for other industrial processes.

Predictive capability evaluation and optimization of sustainable biodiesel production from oleaginous biomass grown on pulp and paper industrial wastewater

Biodiesel, as a green fuel, acts as a potential candidate to supplement conventional fossil fuels. This research study targets green environment (using biodiesel) and clean environment (reduce wastewater) by producing biodiesel through oleaginous biomasses (Yarrowia lipolytica, Metschnikowia pulcherrima and Lipomyces starkeyi) grown on pulp and paper industrial wastewater. Batch culture studies were explored for the potential feedstock of the oleaginous organism by the synthesis of single cell oil and fatty acid methyl ester (FAME) yield. Response surface methodology (RSM) was used to design the optimal experimental matrix and identify the optimal process conditions that enhance the FAME yield. To determine the inherent characteristics of the growth of oleaginous biomasses on the industrial wastewater, a data-driven adaptive neuro-fuzzy inference system (ANFIS) is implemented. Y. lipolytica strain cultured shown high biomass concentration of 32.36 g/l with biomass productivity of 5.39 g/l/d was considered for further scale-up for the transesterification process. Results indicated that the maximum yield of 0.48 (g-biodiesel/g-lipid) was obtained under the 2.5 g of lipid dosage with 0.02 g/ml of catalyst concentration by constant stirring at 70 °C. The optimum conditions to achieve maximum FAME yield of 1.154 g/g was obtained at 2.485 g, 70.87 °C and 0.021 g/ml for lipid dosage, temperature and catalyst concentrations, respectively.

In Situ Transesterification of Spirulina Microalgae to Produce Biodiesel Using Microwave Irradiation

The present technology of transesterification of vegetable oils to produce biodiesel, which is suited to replace petrodiesel, has economic challenges, and therefore, alternative sources are being explored. Microalgae, a renewable, third-generation biofuel resource, have the potential to become a viable feedstock due to their high oil content and environmentally friendly nature. The present study investigates the effect of microwave irradiation on the simultaneous extraction and transesterification of algae lipids to produce fatty acid methyl ester (FAME), in a batch reaction system using sulphuric acid catalyst. In situ transesterification combines the two steps of lipid extraction and transesterification into a single step. The microwave synthesis unit comprised of a 3-neck round bottom flask inside a 1300-Watt microwave oven, fitted with a quick-fit condenser and having an external stirrer. Response surface methodology (RSM) was used to analyse the influence of process variables, dry algae to methanol ratio 1 : 4 − 1 : 14 g / ml , algae biomass to catalyst ratio 1 : 0.0032 − 1 : 0.0368 wt % , and reaction time 1 − 11 min , at 500 rpm stirring rate for in situ reaction. FAME was analysed using gas chromatography (GC). The total lipid content of Arthrospira Spirulina platensis microalgae biomass was found to be 10.7 % by weight. The algae biomass also contained proteins at 51.83 % , moisture content at 7.8 % , and ash content 14.30 % by weight. RSM gave the optimum process conditions as dry algae biomass feed to methanol wt / vol ratio of 1 : 9, catalyst concentration of 2 wt % , and reaction time of 7 minutes for a maximum FAME yield of 83.43 wt % . The major fatty acid composition of FAME was palmitic 43.83 % , linoleic 38.83 % , and linolenic 19.41 % . FAME properties obtained according to European Standards (EN 14214) and American Society for Testing and Materials (ASTM D 6751) standards were as follows: flash point 16 4 o C calorific value 32,911 kJ / kg , acid value 0.475 KOH / g , viscosity 4.45 m m 2 / s , and specific gravity 0.868 . The study showed that Arthrospira Spirulina platensis microalgae lipid FAME met the biodiesel standards (EN 14214 and ASTM D 6751) and has the potential to replace petrodiesel. Microwave irradiation increased the reaction rate resulting in a reduced reaction time of 7 minutes (as compared to 8 hours for conventional heating) and therefore was found to be a superior heating mode as compared to conventional heating.

Titania-termite hill composite as a heterogeneous catalyst: preparation, characterization, and performance in transesterification of waste frying oil

AbstractTo reveal the catalytic potential of abandoned naturally occurring material, we synthesized titania-termite hill composite (Ti-THC) via an incipient wetness impregnation route, characterized by various techniques and tested as a catalyst for transesterification of waste frying oil (WFO). The reusability of the prepared catalyst was also studied to evaluate its stability. The effects of reaction process parameters, such as temperature, time, catalyst loading and methanol/WFO molar ratio on fatty acid methyl ester (FAME) yield, were investigated using a central composite design approach. SEM result revealed pores formation on the catalyst surface, while XRD and EDX analyses confirmed successful insertion of titania into the aluminosilicate layer of the termite hill. The maximum FAME yield of 90.78% was obtained at optimum experimental conditions of 71.16 °C reaction temperature, 2.12 h reaction time, 1.03 wt.% catalyst loading and 9.96:1 methanol/WFO molar ratio. The catalyst still maintained its better stability after being reused for three reaction cycles.

Kinetic modeling and development of optimal trajectories for biodiesel production using multi-objective optimization

A kinetic model has been developed based on the experimental data in the open literature for the simultaneous esterification of myristic acid and transesterification of rapeseed oil with methanol by using sulphated zirconia catalyst at three different temperatures (120 °C, 150 °C, 170 °C) and methanol to oil ratio (20:1). The developed kinetic model has been utilized for the cross-validation of methanol to oil ratio of 10:1 and 4:1 and at a temperature of 170 °C, which is in accordance with the experimental data. Furthermore, the validated kinetic model has been extended to find the optimal process conditions for the desired conflicting objectives. Trade-off solutions for this process are obtained by utilizing the non-dominated sorting genetic algorithm (NSGA-II). The objective is to obtain maximum FAME (fatty acid methyl ester) in minimum methanol to oil ratio and minimum reaction temperature. Addition of oil, methanol, myristic acid and temperature are considered as decision variables with relevant process constraints. A wide range of choices have been obtained for the present optimization setup. The yield of FAME is strongly depends on the reaction temperature, reaction time and methanol to oil ratio. The optimal methanol to oil ratio of 10–15 is sufficient to enhance the FAME yield. • Kinetic modeling of simultaneous Transesterification and esterification. • Kinetic parameter estimation using RCGA. • Formulation of Multi-objective optimization. • Pareto optimal set obtained for the desired conflicting objectives.