Methyl Ester Production Research Articles

Chemical quantification of N-acyl alanine methyl ester (NAME) production and impact on temporal gene expression patterns in Roseovarius tolerans EL-164

BackgroundPrevious studies have identified structurally diverse N-acyl amino acid methyl esters (NAMEs) in culture extracts of Roseovarius tolerans EL-164 (Roseobacteraceae). NAMEs are structural analogues of the common signaling compounds N-acyl homoserine lactones (AHLs), but do not participate in AHL-mediated signaling. NAMEs show minor antialgal and antimicrobial activity, but whether this activity serves as the primary ecological role remains unclear.ResultsTo enable dose-dependent bioactivity-testing, we have established a chromatographic method for quantification of NAMEs in bacterial culture extracts. The concentrations determined for the two major NAMEs produced by EL-164, C16:1-NAME and C17:1-NAME, ranged between 0.685 and 5.731 mg L− 1 (2.0-16.9 µM) and 5.3–86.4 µg L− 1 (15.0-244.3 nM), respectively. Co-quantification of the C14:1-AHL showed concentrations ranging between 17.5 and 58.7 mg L− 1 (56.6-189.7 µM). We observed distinct production patterns for NAMEs and AHLs, with a continuous NAME production during the entire incubation period. We conducted a spike-in experiment, using the determined metabolite concentrations. By comparing the transcriptomes of pre- and post-metabolite-spikes, we identified three clusters of differentially expressed genes with distinct temporal expression patterns. Expression levels of stress response genes differed between NAME- and AHL-spiked EL-164 cultures in the stationary phase.ConclusionsOur findings support previous studies suggesting an ecological role for C16:1-NAME as antibiotic, by proving that NAME concentrations in batch cultures were higher than the minimal inhibitory concentrations against Maribacter sp. 62 − 1 (Flavobacteriia) and Skeletonema costatum CCMP 1332 (Coscinodiscophyceae) reported in the literature. Our study further exemplified the broad application range of dose-dependent testing and highlighted the different biological activities of NAMEs and AHLs.

Methyl ester production process from palm fatty acid distillate using hydrodynamic cavitation reactors in series with solid acid catalyst

This study aims to optimize the reduction of free fatty acids (FFAs) in palm fatty acid distillate (PFAD) using hydrodynamic cavitation reactors (HCRs) in series and a solid acid catalyst for biodiesel production. Hydrodynamic cavitation is used to accelerate the esterification of FFAs using a heterogeneous acid catalyst. There are three HCRs units, and each HCR composed of a 3D-printed rotor and stator, is separated by flanges and equipped with a basket for holding Amberlyst-15 catalyst. Through response surface methodology (RSM), the esterification process is optimized by adjusting its optimal parameters, namely, methanol (2–12 wt%), circulation time (30–170 min), and rotor speed (1000–3000 rpm). The optimal conditions for achieving a maximum methyl ester purity of 89.76 wt% in converting FFA in first-step esterified oil are 9 wt% methanol (molar ratio of methanol to oil of 4:1), 133 min of circulation time, and 2000 rpm of rotor speed. An 82.48 wt% biodiesel yield is achieved from the HCRs in series under the optimal conditions. Scanning electron microscope images reveal that after the esterification process, there are minor cracks and defects on the catalyst’s resin surface, indicating the presence of residual reactants. Further examination of the catalyst after the esterification process, reveals an average absorption pore diameter of 341.41 Å and BET surface area of approximately 41.68 m2/g. Although there were slight physical changes in the catalyst, HCRs technology offers a viable FFA reduction process that could enhance biodiesel production efficiency. Moreover, the optimized conditions achieved in this study contribute to the advancement of biodiesel production processes and provide insights into the performance of the catalyst used.

Enriching various biodiesel feedstocks with Al2O3 nanoparticles in diesel engines: Performance, emissions, and exergy analysis

The inherent drawbacks of biodiesel, particularly its poor performance in cold climates, necessitate the use of nano-additives to improve its cold flow properties such as the cloud point (CP), pour point (PP), and cold filter plugging point (CFPP). In this study, transesterification was employed to produce methyl esters from waste cooking oil, corn oil, and jatropha oil. These biodiesels were blended with diesel fuel at a 20% biodiesel and 80% diesel volume ratio and enriched with nano-Al2O3 at concentrations of 25, 50, and 100 mg/L. The aim of this study is to evaluate the impact of nano-Al2O3 on engine combustion, performance, exergy, and emissions of diesel engines using different biodiesel feedstocks. The addition of nano-Al2O3 to methyl ester mixtures (JB20A100, CB20A100, and WB20A100) resulted in enhancements in thermal efficiency by 8%, 11%, and 13%, respectively. CO emissions were reduced by 12%, 17%, and 22% for jatropha, corn, and waste cooking oil blends, respectively, with 100 ppm alumina. This reduction in CO emissions can be linked to the enhanced oxidation process facilitated by the high surface area of the nanoparticles, which act as catalysts, promoting more complete combustion. Similarly, UHC emissions decreased by 14%, 18%, and 23%, and smoke concentrations were significantly reduced by 14%, 17%, and 24% across the biodiesel blends. However, the introduction of alumina led to the rise in NOx emissions by 9%, 15%, and 19% for JB20A100, CB20A100, and WB20A100, respectively. The study also revealed increases in cylinder pressure by 2%, 4%, and 8%, and maximum heat release rates by 3%, 6%, and 10% for JB20, CB20, and WB20, respectively, upon the incorporation of 100 ppm Al2O3. Exergetic efficiencies improved by 6%, 17%, and 23% for JB20A100, CB20A100, and WB20A100, respectively, and the sustainability index showed enhancements of 2%, 4%, and 7%. Among the tested blends, WB20 with 100 ppm of nano-Al2O3 demonstrated the most promising results, significantly improving engine exergy, combustion, and performance while mitigating emissions to acceptable levels. This study underscores the potential of nano-additives to advance the sustainability and efficiency of diesel engine operations, particularly in cold climate.

Circulation process of methyl ester production from pretreated sludge palm oil using CaO/ABS catalytic static mixer coupled with an ultrasonic clamp

This study investigates the potential of fused deposition modeling (FDM) three-dimensional (3D) printing techniques for manufacturing catalytic static mixers during biodiesel synthesis. The printed catalytic mixing elements comprises acrylonitrile butadiene styrene (ABS) plastic with 15 wt% calcium oxide (CaO) as a solid catalyst. When the reactants flowed through the CaO/ABS mixing device, the blending and acceleration processes were both significantly impacted. Moreover, their characteristics, performance in biodiesel production, reusability, and economy were analyzed. The effects of methanol to oil (M:O) molar ratio, circulation time, and sonication time on methyl ester (ME) purity were also examined. The results showed that CaO crystals were distributed on the CaO/ABS mixer’s surface, which is crucial for catalytic purposes. During circulation process of ME from pretreated sludge palm oil (PSPO), catalytic static mixer (CSM) and CSM coupled with ultrasound (CSM/US) reactors were employed. The full ultrasonic power of CSM/US reactor of 16 × 400 W (total 6400 W) was operated at 20 kHz frequency. Moreover, the continuous and pulse ultrasonic modes of CSM/US reactor were compared to determine the ME purity and electricity consumption for ME production. For the CSM reactor, 12:1 M:O molar ratio and 8.5 h circulation time were recommended to realize 94.2 wt% ME purity. For the CSM/US reactor, 12:1 M:O molar ratio and 2.25 h circulation time were recommended to achieve 96.5 wt% ME purity. Under the pulsed mode operation, ME purity of 95.09 wt% was achieved, with a reduction in electricity consumption by approximately 37.6 % compared to continuous mode operation. Furthermore, the CaO/ABS catalytic static mixer was determined to be reusable for up to three cycles in both CSM and CSM/US reactors. Thus, CaO/ABS catalytic static mixers assure high purity ME production through FDM 3D printing technology with a CaO solid catalyst.

Recyclability of Zinc Palmitate-Based Composites in Fatty Acid Methyl Ester Production from Oil Feedstocks at Varied Acidity.

Zinc hydroxide nitrate (Zn5) is one of the layered metal hydroxide materials, which has been extensively reported as an effective bifunctional catalyst for biodiesel production from acidic oils. This report gives a comprehensive summary of the reactivity of Zn5 in the methanolysis of various oil feedstocks, plant oils, free fatty acids, and other acidic oils. Notably, as evidenced by this work, Zn5 is highly effective in converting acidic oils [palmitic acid/palm oil (PO)] to fatty acid methyl ester (FAME or biodiesel) at high yields ranging from 80 to 95%, withstanding acid content up to 10% without soap formation. The high FAME yields result from complex methanolysis and hydrolysis processes, e.g., transesterification of triglycerides in the PO, esterification of palmitic acid, and hydrolysis of the triglycerides. Despite this, Zn5 is nonrecyclable because it is unstable in the reaction media and transforms into zinc hydroxide nitrate/zinc palmitate (Zn5/ZnP) composites. The Zn5/ZnP composites were suitable for use in FAME production from PO at 100 °C for 2 h by using a methanol-to-oil molar ratio of 30:1, yielding high FAME yields of 97 and 70.7% in the first and fourth cycles, respectively. This study added better insight into how to effectively produce FAME from oil feedstocks of varying acidity by using zinc layered hydroxide- or zinc carboxylate-based materials.

Thermal Conversion of Coral Waste and its Utilization as Low-Cost Catalyst for Biodiesel Production

This study investigates the thermal conversion of waste coral and its utilization as a heterogeneous catalyst for biodiesel production from soybean oil. In this work, waste coral is calcined at varied temperatures of 800, 900, and 1000°C, and the effect of the calcination temperature on the physicochemical character of the solid is evaluated through Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and basicity measurement. The results show that the higher temperature facilitates the conversion of CaCO3 of the aragonite and calcite phases in raw waste coral into CaO, achieving a complete conversion at the temperature of 1000°C. Thermal conversion influences the increased surface basicity of the solid, which is associated with the higher activity for biodiesel production. Further studies on the obtained CaO as a catalyst demonstrate the catalyst dosage and the methanol-to-oil ratio as significant factors for fatty acid methyl ester production. The highest yield of 98.7% is achieved after a 3 hours reaction with 8 wt.% catalyst dosage and 9:1 methanol-to-oil ratio. The catalyst exhibits stability with an insignificantly decreased yield until the fifth usage cycle. The optimum conditions and reusability features of the calcined waste coral suggest that waste coral is a favorable CaO catalyst source for biodiesel production.

Transesterification catalyst strength as observed by solution-based oxygen-17 nuclear magnetic resonance spectroscopy

Natural abundance oxygen-17 nuclear magnetic resonance spectroscopy (17O-NMR) was applied to study homogeneous transesterification catalysts for fatty acid methyl ester production. Alkoxide catalysts were made with selected permutations of lithium, sodium, magnesium, and potassium hydroxides with ethanol, methanol, isopropanol, and glycerol. Pilot scale transesterification reactions of Canola oil were completed and the 17O-NMR spectra were collected from the reaction products. The alkoxide solutions showed the downfield shifts relative to the reagent alcohol, in a linear relationship with the concentration of catalyst ion. The electron deshielding of the oxygen of the alkoxide catalyst is observed directly by 17O-NMR, and the fastest catalyst has the largest downfield (high frequency) shift. This effect is most pronounced in potassium methoxide and less pronounced for less polar solvents such as isopropanol.

Comparative Studies on Methyl Ester Production from Pretreated Sludge Palm Oil Using Homogeneous and Heterogeneous Base Catalysts

A heterogeneous base catalyst transesterification process with a calcium oxide (CaO) catalyst was performed to produce high-purity methyl ester (ME) from pretreated sludge palm oil (PSPO) derived from sludge palm oil (SPO). Additionally, a comparative analysis was conducted with potassium hydroxide (KOH) as a homogeneous base catalyst to assess the distinctions between heterogeneous and homogeneous base catalysts. The response surface methodology (RSM) was utilized to determine the optimal and recommended conditions for both transesterification processes. For heterogeneous transesterification, a varying CaO catalyst loading (10–60 wt.%), methanol (25–65 wt.%), and reaction time (60–180 min) were essential parameters. Meanwhile, homogeneous transesterification involved investigating the KOH catalyst loading (1–3 wt.%), methanol (1.8–5.5 wt.%), and reaction time (20–60 min). For the heterogeneous-base-catalyzed reaction, the recommended conditions were as follows: a molar ratio of methanol to oil of 5.83:1 (41.61 wt.%), 31.3 wt.% CaO, and a reaction time of 119.0 min, which resulted in a ME purity of 96.51 wt.%. The optimal conditions for homogeneous transesterification were a molar ratio of methanol to oil of 0.49:1 (3.45 wt.%), a 40 min reaction time, and a 1.39 wt.% KOH concentration, which achieved 96.59 wt.% ME and met the standard.

Methyl esters production from Waste Cooking Oil catalysed by iron oxides supported on CaO: Cost and environmental impacts

It was the objective of this work, to assess the midpoint environmental impacts of the catalyst synthesis stage and biodiesel production from waste cooking oil (WCO) as feedstock, depending on the catalyst source, i.e. Fe2O3 or Fe(NO3)3⋅9H2O, lime or waste clam shells, to produce the applied bifunctional catalyst based on iron and CaO. The cost of biodiesel production depending on the catalyst was also established. In the catalyst synthesis stage, the use of clam shells contributed the most to the midpoint environmental categories, mainly terrestrial ecotoxicity, freshwater ecotoxicity, marine ecotoxicity and human non-carcinogenic toxicity. In the stage of biodiesel production (esterification-transesterification reaction), the scenario contributing the lowest (20.95–22.16 %) to the midpoint environmental impacts is when using Fe(NO3)3·9H2O and CaO as iron and lime precursors, respectively. Using waste clam shells increases the environmental impacts. Regarding costs, the clam shells lead to the most expensive process ($0.08 USD/MJ). The source of energy to conduct the biodiesel production was also assessed and it was found that the use of wind turbines leads to the lowest global warming potential (GWP), 11.6 g CO2 eq·MJ-1, with the catalyst prepared with the iron salt and with the CaO from lime. The presented results were obtained with the commercial software SimaPro® version 9.6 PhD. For the inventory, experimental data obtained at laboratory scale and previously published were used.It was concluded that based on environmental impacts and costs, it is recommended to use lime instead of clam shells waste as precursor of CaO and Fe(NO3)3·9H2O as precursor of iron.

Methyl Ester Production from Rice Bran Oil and Methanol with Calcium Carbonate Catalysts Using Esterification Method

Rice bran oil is a type of oil with high nutritional value from rice bran. However, the free fatty acid content in it can increase by more than 60% with sufficient storage time. Free fatty acids contained in rice bran have the potential to be produced into biodiesel (methyl ester). This research aimed to determine the effect of methanol volume and esterification process time on biodiesel yield and to compare methyl ester yield to standard biodiesel. This research was conducted in two stages, namely rice bran oil extraction and esterification. In the extraction stage, rice bran was extracted with n-hexane for 3 hours at an operating temperature of 65oC. The esterification process was carried out by mixing rice bran oil, methanol with a certain volume (100, 125, 150, 175, 200 mL), and calcium carbonate catalyst as much as 1% of the amount of methanol. Esterification was carried out with time variations of 1; 1.5; 2; 2.5 and 3 hours. The results in the form of rice bran oil were analyzed for the value of the biodiesel yield. The result of rice bran oil was analyzed for initial free fatty acid value. Pure biodiesel product in the form of methyl ester was obtained through separation with glycerol as a by-product. The optimum methyl ester yield was 81.70% at 175 ml methanol volume for 3 hours. The methyl ester results are in accordance with SNI biodiesel for density and kinematic viscosity values.

Electrolysis Approach of Fatty Acid Methyl Ester Production Using Alkali Hydroxides and Their Alkoxides

The depletion of fossil fuels and environmental concerns have led to the search for alternative fuels (biodiesel) derived from renewable resources. Electrolysis is a promising method of fatty acid methyl ester (FAME) synthesis that can be maintained at room temperature. Nevertheless, the low reaction rates have been commonly accelerated using a combination of catalysts and electrolytes. This work proposed a novel electrolyte-free electrolysis approach for biodiesel synthesis from soybean oil using alkaline hydroxide (NaOH, KOH) and alkaline methoxide (NaOCH3, KOCH3)catalysts. Though all of them demonstrated high biodiesel yield, KOCH3 exhibitedthe highest efficiency. Based on response surface methodology, the highest FAME yield of 97.11% was achieved at optimal electrolysis voltage of 18.76V, water amount of 1.97 wt.%, KOCH3 amount of 3.17 wt.%, and methanol/oil of 21.33:1 molar, and reaction time of 60 min. The fuel properties of synthesized biodiesel agreed with international standards.The findings of this work suggest that electrolyte-free electrochemical using alkaline hydroxides and alkaline methoxides as catalysts could be a useful alternative to conventional transesterification method for producing biodiesel. Keywords: Alkaline catalysts, Biofuel, Box–Behnken Design, Electrochemical approach

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.

Modification of Growth Media for Scenedesmus and Nitchzer Species for Fatty Acid Methyl Esters Production in Raceway Pond

The aim of this study was to modify the growth media for Scenedesmus and Nitchzia species for fatty acid methyl esters production in raceway pond. Native Scenedesmus and Nitchzia species were cultivated in raceway pond in three different growth media (Nitrogen-sufficient, Nitrogen-deficient and Blue Green 11) media at different periods to assess their quantitative parameters (biomass concentration (g/L), biomass productivity (g/L/d), lipid content (%), and lipid productivity (mg/L/d) as well as their fatty acid methyl esters composition. The quantitative parameters were determined following standard methods and the fatty acid methyl esters composition was analysed by Gas Chromatography Mass Spectrometry (GC-MS). The results of the quantitative parameters obtained from Scenedesmus species were highest in the Blue Green 11 (control) media as compared to the experimental media. Statistically, there is significant difference (p<0.05) in the lipid content obtained from Scenedesmus species between the Blue Green 11 media and the experimental media. The biomass concentration and lipid content obtained from Nitchzia species were also found to be highest in Blue Green 11 media as compared to the other two media. However, the lipid content obtained from Nitchzia species in the three different media showed insignificant difference (p>0.05). Scenedesmus and Nitchzia species did not respond to nitrogen deficiency condition. The Gas Chromatography Mass Spectrometry analysis of the fatty acid methyl esters composition revealed the presence of similar compounds in different proportion. The dominant compound of the fatty acid methyl esters of the two species in the three different media are Hexadecanoic acid methyl ester ((palmitic acid)), 9-octadecenoic acid (Z) methyl ester ((oleic acid) and 9, 12-octadecadienoic acid methyl ester (linolenic acid) among others. The Carbon16-Carbon18 (C16-C18) chain in Scenedesmus and Nitchzia species ranges from 74.14-61.84% and 63.81-61.98% respectively. These could suggest that both species have a great potential for the production of fatty acid methyl esters in large scale cultivation.

Nano-CaO as a heterogeneous catalyst for biodiesel synthesis by transesterification of Jatropha oil

BackgroundThis research employs response surface methodology, specifically Central Composite Design (CCD), to optimize the process parameters for the effective production of biodiesel. Jatropha oil was utilized as the raw material to minimize expenses. A nanocatalyst was utilized as a solid catalyst, developed from CaCO3 via waste snail shells, offering advantages such as recyclability and improved catalytic activity during a transesterification process. The developed nanocatalyst was analyzed using various techniques, including dynamic light scattering (DLS), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and Fourier-transform infrared (FTIR). The BET analysis revealed a surface area of 5.1m2/g and the Barrett-Joyner-Halenda (BJH) analysis provided insights into the pore volume and diameter of the synthesized nano-CaO, showing values of 0.002556 cc/g and 1.1 nm, respectively, indicating the presence of both microspores and active sites on the external surface of the nano-CaO catalyst. Biodiesel conversion was controlled by adjusting factors like the methanol to oil ratio, catalyst weight, reaction time, reaction temperature, and agitation speed. A quadratic model was established to explore the correlation between the independent variables and the biodiesel conversion rate. The results showed a maximum biodiesel conversion rate of 96.73% under the optimal conditions: methanol to oil ratio (6:1), catalyst weight (1.4 wt%), reaction time (60 min), reaction temperature (55 °C), and agitation speed (250 rpm). These parameters were determined through 32 experimental trials. The RSM technique yielded impressive results with a determined coefficient of determination (R2) of 0.9834, adjusted R2 of 0.8503, predicted R2 of 0.8309, and a coefficient of variance (CV) 0.75%. Based on the analysis of variance (ANOVA) findings, the model exhibits a high level of significance (p<0.0001), which is less than 0.05 and F- Value 29.71.The study aims to enhance the yield and efficiency of the transesterification process, thereby increasing the overall production of fatty acid methyl ester from Jatropha oil. This innovative approach efficiently generates biodiesel from renewable resources, in a manner that is both environmentally friendly and maximizes the effectiveness of the process parameters. The evaluation conform that the quality of the biodiesel met the standards set by ASTM D 6751 and EN 14214.

[formula omitted] -catalyzed trans-esterification of brassica carinata seed oil for biodiesel production

Brassica carinata seed is a non-edible oil containing crop grown for oil-based product development like biodiesel synthesis. However, recently technical challenges such as availability of feedstock, type of catalyst, cost, and quality of biodiesel hindered the feasibility and utilization of biodiesel. Thus, this study addressed those problems under the production of fatty acid methyl ester through trans-esterification reaction in the presence of heterogeneous catalyst (CaO), and methanol alcohol from Ethiopian brassica carinata seed oil. The synergetic and antagonistic effects of selected parameters (temperature, methanol to oil molar ratio, and amount of catalyst) on the yield of FAME were analyzed. Box-Behnken response surface methodology statistical analysis was applied to examine the parametric interaction effect, and optimization of reaction conditions. Accordingly, 90 % of fatty acid methyl ester (FAME) yield was achieved at the optimum value of 65 °C temperature, 14.85: 1 methanol to oil molar ratio, and 13.77 % catalyst load. The fuel properties of the resulted biodiesel were determined following standard procedures, and the results were within the standard limits (ASTM D6751). This implies that brassica carinata oil over heterogeneous catalyzed reaction medium under optimum reaction conditions provides higher biodiesel yield.

OPTIMIZATION OF YELLOW OLEANDER BIODIESEL PRODUCTION PARAMETERS USING CENTRAL COMPOSITE DESIGN RESPONSE SURFACE METHODOLOGY

Response surface methodology was used for optimization of methyl ester production parameters with the two-step trans- esterification of Yellow oleander seed oil. The model equation obtained with R2, 0.877 and coefficient of variation (CV), 3.21% shows the reliability of the model and adequately captured the correlation between the biodiesel yield and process parameters. The result suggested the best combination of the process variables for optimum biodiesel yield of 91.42% are: reaction temperature (46.61 °C); reaction time (90.52 min); amount of methanol (5.90 cm3/g oil) and catalyst concentration (11.44gm). Validation results show close agreement between the actual (90.85%) and predicted (91.42%) biodiesel yields.

Heterogeneous Calcium Oxide Catalytic Filaments for Three-Dimensional Printing: Preparation, Characterization, and Use in Methyl Ester Production.

This study aimed to investigate heterogeneous catalytic filaments of calcium oxide (CaO) for fused deposition modeling three-dimensional (3D) printers. The CaO catalysts were blended with acrylonitrile butadiene styrene (ABS) plastic to form catalytic filaments. A single-screw filament extruder was used to prepare the filaments, following which their mechanical properties, thermal properties, morphology, catalytic characteristics in biodiesel production, and reusability were evaluated. In accordance with the results, a maximum CaO catalyst content of 15 wt % was recommended to be blended in the ABS pellet. The hardness and compressive strength of these catalytic filaments were shown to be improved. Subsequently, the catalytic filaments with the highest CaO content (15 wt %) were used to produce methyl ester from pretreated sludge palm oil through the transesterification process. To determine the recommended conditions for achieving the highest purity of methyl ester in biodiesel, the process parameters were optimized. A methyl ester purity of 96.58 wt % and a biodiesel yield of 79.7 wt % could be achieved under the recommended conditions of a 9.0:1 methanol to oil molar ratio, 75.0 wt % catalytic filament loading, and 4.0 h reaction time. Furthermore, the reusability of the 15 wt % CaO catalytic filaments was evaluated in a batch process with multiple transesterification cycles. The results indicated that the purity of methyl ester dropped to 95.0 wt % only after the fourth cycle. The method used in this study for preparing and characterizing CaO catalytic filaments can potentially serve as a novel approach for constructing biodiesel reactors using 3D printing technology.

Synthesis of microalgae-based methyl ester using calcium glyceroxide catalyst derived from duck eggshells and crude glycerol in the n-hexane co-solvent system

Abstract The synthesis of microalgae-based methyl ester has attracted the interest of researchers since microalgae have a high lipid content and can proliferate. Chlorella vulgaris, with its 63% lipid content on a dry basis, holds promise for methyl ester production. Heterogeneous catalysts, particularly calcium glyceroxide (Ca[O(OH)2C3H5]), play a crucial role in ester manufacturing due to their high catalytic activity. The synthesis of the calcium glyceroxide catalyst involves duck eggshells as a calcium source and crude glycerol. Optimal methyl ester production is achieved by employing n-hexane as a co-solvent for efficient microalgae oil dissolution. This research focuses on synthesizing and characterizing the calcium glyceroxide catalyst derived from duck eggshells and crude glycerol, emphasizing its application in manufacturing microalgae-based methyl esters with n-hexane as the co-solvent. Methyl ester synthesis variables include a 55°C reaction temperature, a 1.5% microalgae-derived catalyst, and a 9:1 methanol to microalgae ratio. FTIR functional group analysis identifies hydroxyl (O-H) groups from crude glycerol bound to calcium at 3345.71 cm−1, along with C-H group vibrations from crude glycerol bound to calcium at 2941.80 cm−1. SEM morphological analysis reveals aggregate formation on the calcium glyceroxide catalyst, indicating potential active sites. Utilizing the calcium glyceroxide catalyst for methyl ester synthesis yields a promising 62.42% yield. GC characterization demonstrates a methyl ester purity of 72.09%, with methyl palmitate as the predominant component at 30.927%. This study underscores the efficient use of the synthesized calcium glyceroxide catalyst for microalgae-based methyl ester production, showcasing its potential for sustainable biodiesel synthesis.

PREPARATION AND CHARACTERIZATION OF BENTONITE CLAY CATALYSTS FOR TRANSESTERIFICATION OF WASTE COOKING OIL INTO BIODIESEL

The development of low-cost green catalytic materials is crucial for the conversion of non-edible vegetable oils or waste materials into biodiesel. The research focuses on the preparation and characterization of aluminium pillared clay and NaOH-doped bentonite clay catalysts for biodiesel production from waste cooking oil using XRF, XRD, FTIR and N2 adsorption-desorption techniques. The molecular profile and functional group assessment of the biodiesel were done using GC-MS and FTIR respectively. XRF analysis revealed the presence of oxides in all samples. The amount of SiO2 in all samples was within the range of 35.303–39.199 wt%. Al2O3 increased from 15.560 to 19.11 wt%, while the interlayer cations decreased after pillaring. FTIR revealed the appearance of peaks which are characteristic of bentonite. The pillaring and impregnation of NaOH with bentonite led to a distortion of certain peaks' intensity, as evidenced by FTIR results. The pillaring caused an increase in BET surface area and pore volume compared to bentonite from 302.1 to 366.4 m2/g, and 0.186 to 0.189 cc/g respectively, while a decrease in surface area and pore volume was observed in NaOH/bentonite due to impregnation. The XRD data have shown the increase of basal d-spacing of pillared clay from 12.65 to 16.49 Å relative to bentonite with a decrease to 12.45 in the case of NaOH/bentonite. The catalysts prepared outperformed neat bentonite with NaOH/bentonite, resulting in the highest yield of (83 ± 1.80). GC-MS, FTIR, and physicochemical analyses confirmed the production of fatty acid methyl esters.

Synthesis of Methyl Ester from Microalgae Chlorella sp. TAD Using the In-Situ Transesterification Method

Synthesis of methyl ester from Chlorella sp. TAD microalgae was carried out using the in-situ transesterification method. This study aims to determine the methyl ester composition of Chlorella sp. TAD microalgae using the in-situ transesterification method. The in-situ transesterification method is a modified method that allows extraction and transesterification into methyl ester products in one process simultaneously. The in-situ transesterification process lasted 8 hours, followed by a distillation process to remove the n-hexane content and an oven for 2 hours to evaporate the remaining water. The results of the analysis using GC-MS to determine the chemical content of the methyl ester compound from Chlorella sp. TAD, showed the methyl ester composition of 7,10-hexadecanoic methyl ester, 8,11,14-docosatrienoic methyl ester, 9-hexadecanoic methyl ester, hexadecanoic methyl ester, heptadecanoic methyl ester, 10-octadecenoic methyl ester, octadecenoic methyl ester, 9,12-octadecadienoic methyl ester, 10-octadecenoic methyl ester, 2-hexyl cyclopropaneoctanoic methyl ester, eicosanoic methyl ester, 10-heptadecen-8-ynoic acid methyl ester, nonahexacontanoic methyl ester, and tetracosanoic methyl ester.