Biodiesel Production Reaction Research Articles

Production of biodiesel (isopropyl ester) from coconut oil by microwave assisted transesterification: parametric study and optimization

Biodiesel, a renewable fuel for diesel vehicle engines, has been commonly produced from transesterification process involving triglycerides from vegetable oil with alcohol. One of the most promising candidates for vegetable oil due to its abundance in Indonesia is coconut oil. However, the short carbon chain present in coconut oil necessitates the use of longer-chain alcohol types to adjust to the biodiesel carbon chain, such as isopropanol. Therefore, this research focused on producing biodiesel (isopropyl ester) from coconut oil using isopropanol and NaOH catalyst through a transesterification process. To enhance this process, microwave technology was utilized for its ability to lower the biodiesel production reaction time from the conventional one-hour timeframe to less than ten minutes, increase energy efficiency, and improve biodiesel quality. The primary objective was to investigate the impact of reaction time, catalyst concentration, and microwave power on the isopropyl ester yield. Further optimization was conducted using Response Surface Methodology (RSM) with Box-Behnken Design (BBD) to illustrate the model's effectiveness and applicability. Based on BBD optimization simulation, the optimal condition for producing isopropyl ester from coconut oil using microwave technology is a 1-minute reaction time, 0.2 wt.% NaOH catalyst concentration, and 443.9 W microwave power, maximizing the yield to 99.89%. This research highlights the potential of microwave assisted transesterification and the reliability of this innovative approach, contributing to the development of isopropyl ester production with enhanced quality that meets the specifications of the Indonesian National Standard (SNI).

Various methods for enhancement in heterogeneous catalysed biodiesel production reaction rate

The biodiesel can be produced by transesterification and esterification reaction with edible and non-edible oil respectively. These reactions are catalysed by both homogeneous and heterogenous catalyst. The transesterification reactions for heterogeneous catalysts proceed at a relatively slow rate. The heterogeneous reaction mixture constitutes a three-phase system, oil/alcohol/catalyst therefore the mass transfer limitation controls the reaction rate. In the present study Tetra-hydrofuran, Hexane and Heptane as co-solvent have been tested for the transesterification and esterification reaction. Tetra-hydrofuran, assists in decreasing the mass transfer between the oil and methanol phases. Tetra-hydrofuran was found to be the best co-solvent. It also represents that the presence of Tetra-hydrofuran only enhance the solubility of phases not final equilibrium yield. Results are compared with homogeneous and heterogeneous catalysed reaction. Ultrasonic irradiation influenced the mixing of the reaction mixture and resulted in higher yields, for each co-solvent case.

Phenomenological modeling of polyols, citric acid and bio-oil concurrent production by Yarrowia lipolytica from glycerol

Biochemical routes have shown to be an interesting alternative for the reuse of glycerol, largely generated as a co-product in biodiesel production reaction. Previous works from the research group have demonstrated that glycerol can be efficiently assimilated by Yarrowia lipolytica to produce erythritol, mannitol, citric acid and bio-oil. To better understand the metabolic pathways involved, this work proposes a mathematical model to describe the observed phenomenon. This is the first computational work to model polyol's production and to address the simultaneous formation of four products by Yarrowia lipolytica. Particle Swarm Optimization and Interior Point Optimization were employed together to find the global optima. The developed model proved to be significantly promising and capable of satisfactorily predict the system's behavior in more than one experimental condition. Not only products’ concurrent formation was accurately described, but also polyols’ modeling was successfully performed, reaching R² values greater than 0.93.

Enhancement in Activity and Reusability of Dry Amberlyst-15 Catalyst by Thermal Treatment for Production of Biodiesel from Karanja Oil

The effect of preheating Amberlyst-15 catalyst used for the biodiesel production reaction of Karanja oil was studied. The preheated Amberlyst-15 samples were characterized for their surface area and pore volume and by SEM, TGA and FTIR spectroscopy. A preheat temperature of 473 K was found to optimum. At this temperature, the surface area had increased and the sulfonic acid groups of Amberlyst-15 were retained. At 473 K preheated Amberlyst-15 gradually deactivated with reuse from a biodiesel yield of 85% to 27% in four runs at a reaction temperature of 393 K and methanol to oil ratio of 60:1. For the power-law model, the reaction order was 0.65, the rate constant at 373 K was 0.027 h-1 and activation energy was 86.98 kJ/mol.

Green synthesis of biodiesel from microalgae cultivated in industrial wastewater via microbubble induced esterification using bio-MOF-based heterogeneous catalyst

Conventional homogeneous catalysts are non-biodegradable, requiring complicated downstream separation, further diminishing the overall economics. In this paper, a new heterogeneous catalyst, a metal-organic framework modified by biomaterials (Bio-MOF), complexed with an ionic liquid ([HMIM][HSO4]/Bio-MOF), has been synthesized and integrated with microbubble mediated mass transfer technology to overcome the challenges of low conversion. The ionic liquid 1-methylimidazole hydrogen sulfate provides enhanced reactivity, while the Bio-MOF provides more active sites for the reaction. Detailed kinetic analysis suggests the biodiesel production reaction occurs on the vapor/liquid (microalgae oil) interface. The results revealed a higher conversion of (molar ratio of oil: methanol =1: 15, catalyst loading = 0.5 wt% of MO, temperature = 70 ºC) 92 ± 4% was achieved in 30 min relative to acid-catalyzed biodiesel production. Along with higher reactivity and larger surface area provided by the catalysts, the unprecedented higher conversion and rate of reaction is attributed to the “local” excess of alcohol present at the interface and simultaneous removal of water from the reactor. The results of activation energy (7.9 kJ mol−1), enthalpy (4.92 kJ mol−1), entropy (−287 J mol−1), and Gibbs free energy (103.58 kJ mol−1) show that current process required less energy is required for biodiesel production. The catalyst was recycled seven times and showed high stability with little reduction in its activity over these seven runs. The study demonstrates that this newly developed catalyst provides a high reaction rate and conversion of biodiesel production from microalgae oil using a heterogeneous catalyst by integrating it with microbubble-mediated mass transfer.

Green synthesis of heterogeneous polymeric bio-based acid decorated with hydrophobic regulator for efficient catalytic production of biodiesel at low temperatures

Biodiesel is being deemed a kind of important renewable energy source and also shows the great potential to replace fossil fuels to respond to global primary energy demands. However, by-product water generated during the esterification reaction of biodiesel production is not conducive to the forward progress of the reaction, and even affects the pristine structure and activity of the employed catalytic material. In this work, the hydrophobic polymeric bio-based solid acid catalyst FDCA/SA-UiO-66(Zr) was prepared by a facile grinding method using biomass-derived stearic acid (SA) and 2,5-furandicarboxylicacid (FDCA) as hydrophobic ligand and green organic linker, respectively. Accordingly, the corresponding characterization results showed that the relevant material had a good particle shape along with a highly hydrophobic network (136.4°), wherein the significant hydrophobic environment was determined to promote the adsorption of lipophilic acid and the desorption of water on the Lewis acid site. Compared with traditional heterogeneous and homogeneous acid catalysts, just at a low temperature (60.2 °C, 98.4% yield), FDCA/SA-UiO-66(Zr) exhibited superior or equivalent catalytic performance in the esterification of FFAs for biodiesel manufacture. More importantly, thanks to the stable skeleton structure of UiO-66(Zr), the catalyst demonstrated a stable structure and good reusability during 6 consecutive recycles (92.5% biodiesel yield).

An experimental investigation on the effect of surfactant for the transesterification of soybean oil over eggshell-derived CaO catalysts

• Nonylphenol ethoxylates was used as a co-solvent in transesterification reaction. • The use of surfactant accelerates the rate of the biodiesel production reaction. • CaO catalyst from eggshells showed high efficiency in biodiesel production. • The use of surfactant decreases the required alcohol/oil ratio. • The thermogravimetric analysis proved to be efficient for determining the FAME yield. Biodiesel is a biodegradable and renewable fuel, that generally consists of fatty acid methyl ester (FAME) produced by transesterification of lipids using methanol and a catalyst. Calcium oxide (CaO) is a heterogeneous catalyst that has been extensively studied to produce biodiesel due to its high catalytic activity. In addition, and in order to avoid mass transfer limitations that would slow down the reaction, it is also common to use a co-solvent. Thus, this work aims to evaluate the use of the surfactant Nonylphenol seven Ethoxylates (NP7EO) for the CaO-catalyzed transesterification of soybean oil. For this study, chicken eggshell was the source of calcium used to produce the CaO for the reaction. This work represents one of the few articles where transesterification was performed using a surfactant combined with a biobased and residual source of Ca. An experimental design was performed to evaluate the surfactant concentration and reaction time. Another factorial experimental design was carried out considering factors such as reaction time, catalyst concentration, and methanol-to-oil molar ratio. Ultimately, the model predicted by the experimental design was shown to be significant and the highest yield obtained after a 3 h reaction time was 98.95% with a 5 wt% catalyst loading and a 7:1 methanol-to-oil molar ratio using 1 wt% of surfactant and operated at 65 °C. The results showed that the surfactant allowed reducing the methanol-to-oil molar ratio and reaction time, which ultimately could contribute in decreasing the biodiesel production costs.

Lipase Immobilization on Macroporous ZIF-8 for Enhanced Enzymatic Biodiesel Production.

Immobilization of enzyme on metal–organic frameworks (MOFs) has drawn increasing interest owing to their many well-recognized characteristics. However, the pore sizes of MOFs (mostly micropores and mesopores) limit their application for enzyme immobilization to a great extent owing to the large size of enzyme molecules. Synthesis of MOFs with macropores would therefore solve this problem, typically encountered with conventional MOFs. In this work, macroporous zeolitic imidazolate frameworks (ZIF-8), referred to as M-ZIF-8, were synthesized and used for immobilization of Aspergillus niger lipase (ANL). Immobilization efficiency using M-ZIF-8 and enzymatic catalytic performance for biodiesel preparation were investigated. The immobilized ANL on M-ZIF-8 (ANL@M-ZIF-8) showed higher enzymatic activity (6.5-fold), activity recovery (3.8-fold), thermal stability (1.4- and 3.4-fold at 80 and 100 °C, respectively), reusability (after five cycles, 68% of initial activity was maintained), and porosity than ANL on conventional ZIF-8 (ANL/ZIF-8). In addition, by using ANL@M-ZIF-8 for catalyzing a biodiesel production reaction, a higher fatty acid methyl ester yield was achieved.

Natural soil and lithium carbonate as economical solid-base catalysts for biodiesel production

Natural soil contains Si and Al compounds suitable for catalysis biodiesel production reactions. Catalytic activity related to biodiesel production was investigated using two soil types mixed with Li2CO3 as the alkali metal catalysts. The method used for heterogeneous transesterification catalyst preparation using soil was straightforward: one-pot blending and grinding of soil with Li2CO3 followed by heating at 700 °C for 4 h. The physical and chemical properties of prepared solid-base catalyst were characterized through X-ray diffraction (XRD), Brunauer–Emmett–Teller surface area (BET), Fourier transform infrared spectroscopic (FTIR) and field emission scanning electron microscope (FE-SEM). The optimal conditions for transesterification involved mixing methanol and oil at a molar ratio of 36:1 at 65 °C with 8 wt% alkali catalyst. The results demonstrated that the conversion rate of seven oils to fatty acid methyl esters was in the range of 98%–99%. Thus, the application of natural soil in catalyst preparation for biodiesel production is cost-effective and ecofriendly.

Synthesis of nanocomposites cellulose-Fe3O4/ZnO as novel green catalyst for biodiesel production from coconut oil

Cellulose-Fe3O4/ZnO nanocomposites have been successfully synthesized. This process was supported by characterization using Fourier Transform InfraRed (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Scanning Electron Microscopy-Mapping (SEM-Mapping) instruments. The successfully synthesized-nanocomposites then were tested for a catalytic activity in the transesterification reaction to form biodiesel. The results of the biodiesel production were characterized using Gas Chromatography - Mass Spectroscopy (GC-MS). The highest conversion of coconut oil into biodiesel was 90.6%, with a catalyst amount of 0.6% wt and a 120 minutes reaction time. The biodiesel production using GC-MS shows that the most formed-methyl esters are dodecanoic acid methyl esters (lauric acid methyl esters). The use of cellulose as a catalyst support by combining Fe3O4/ZnO composites is very promising to be a green catalyst in the reaction of biodiesel production.

Efficient transesterification over two-dimensional zeolites for sustainable biodiesel production

Basic zeolites have shown great potential as efficient catalysts for biodiesel production in the transesterification reactions. However, conventional three-dimensional (3D) basic zeolites generally suffer from limited base sites and severe mass-transfer restriction, thereby suppressing their catalytic activity. Herein, 2D basic zeolites with large external surface areas, hierarchical characteristics, and abundant accessible and stable base sites are prepared by expansion, delamination and subsequent solid-state ion-exchange (SSIE) approach. The facile SSIE method provides more advantages in stabilizing and dispersing high concentration of strong basic sites than the conventional liquid-phase ion-exchange (LIE) approach. Due to the excellent mass transportation and stable basic sites, the 2D Na/ITQ-2 prepared by the SSIE approach shows remarkably enhanced activity and recyclability in the transesterification of triglycerides to produce biodiesel, compared to 3D zeolites and other reported basic zeolites. This work will open the boulevard to the rational design of 2D basic catalysts and expand the potential application of 2D zeolites to biodiesel production and other industrial reactions involving bulky molecules.

Evaluation of the catalytic effect of ZnO as a secondary phase in the Ni0.5Zn0.5Fe2O4 system and of the stirring mechanism on biodiesel production reaction

In search of efficient ways to produce biodiesel under environmentally friendly conditions, catalytic reactions have been explored with emphasis on replacing homogeneous by heterogeneous catalysis with the use of new catalyst types, such as the spinel ferrites, which are described as a viable option, since they are stable, highly active, inexpensive, reusable, and allow the easy recovery of the reaction medium through the application of magnetic fields. In this context, the present work proposes to contribute to the consolidation of the catalytic viability of the Ni0.5Zn0.5Fe2O4 system obtained by combustion reaction, because although previous studies indicate the catalytic effectiveness of this system in polyphasic form, the present work seeks as differential to evaluate the influence of the secondary phases and magnetization of the Ni-Zn system in the conversion to biodiesel, and for this purpose, it aims to evaluate the catalytic effect of ZnO formed as secondary phase and obtained concomitantly in the Ni-Zn ferrite synthesis, besides evaluating the effect of the stirring mechanism used in biodiesel production reaction by the ethyl transesterification of soybean oil. The synthesized Ni-Zn ferrites and ZnO sample were characterized by X-ray diffraction (XRD), nitrogen adsorption textural analysis (BET), particle size distribution, and then, tested in two reactor types, one with magnetic stirring, and another of mechanical stirring, to observe the magnetization effect of the material, and the characterization of the obtained biodiesels by gas chromatography (GC) and acidity index. The performed catalytic tests showed that the Ni-Zn ferrites promoted excellent ester conversions with values near and above 94%, thus confirming that although ZnO also promotes good ester conversion (83.9%), the catalytic effectiveness of the Ni-Zn ferrite is evident and independent of secondary phases. Moreover, the catalytic tests performed in the magnetic stirring reactor using the Ni-Zn ferrites as catalysts made it possible to realize that their magnetic properties may be interference in the catalytic effectiveness, being this, a more determining factor than the surface characteristics.

Conventional vs. hybrid methods for dispersion of MgO over magnetic Mg–Fe mixed oxides nanocatalyst in biofuel production from vegetable oil

In this research, MgO/MgFe2O4 heterogeneous magnetic nanocatalyst was used in biodiesel production and to study its structural and morphological characteristics, various methods have been used in MgO addition on the support. Impregnation, Precipitation, Precipitation – Hydrothermal, Precipitation – Ultrasonic and Combustion methods were utilized to add the MgO on the MgFe2O4 to find the suitable surface structure and catalytic activity. Combustion synthesis was used as a facile and low cost preparation route for fabrication of all nanocatalysts’ support because of suitable porosity for the biodiesel production reaction. For this purpose, the samples were analysed by XRD, FESEM, EDX, BET-BJH, and FTIR and then used in the transesterification reaction. Results indicate the sheet like morphology in precipitation and precipitation-hydrothermal methods and lower particle size in combustion synthesized nanocatalyst. Suitable surface structure and proper pore size and volume caused the combustion prepared sample to score the highest yield of 92.9% in biodiesel production from sunflower oil. This sample showed proper stability and reusability potential while the structure remained intact after five times being used in the reaction. Due to the magnetic characteristic of the support the catalyst separation was easy and this caused negligible catalyst loss.

One-step hydrothermal synthesis of magnetic rice straw for effective lipase immobilization and its application in esterification reaction

Immobilization of industrially important enzymes on supports is important to decrease the cost of the overall enzymatic production procedure. Herein, a novel method for synthesizing a new support, magnetic rice straw (MRS) in one step is reported: rice straw (RS) was soaked with Fe2+ ions and these were further reduced to form embedded Fe2O3 nanoparticles on the RS surface, forming MRS. This material presented a magnetic saturation value of 27.32 emu g−1. Lipase immobilization on MRS resulted in 94.3% immobilization efficiency and 91.3 mg g−1 of enzyme loading, which are higher than immobilization on native RS. The lipase stability was increased approximately 8-fold at 70 °C. The lipase-MRS composite was tested in the esterification reaction of biodiesel production, where it showed prominent reusability. Therefore, this novel and rapid synthesis method can provide ecological and economic support for enzyme immobilization and industrially important product formation.

The use of KOH/Clinoptilolite catalyst in pilot of microreactor for biodiesel production from waste cooking oil

In this study, the transesterification of waste cooking oil and methanol aimed to produce biodiesel and use of KOH/Clinoptilolite as a heterogeneous catalyst in the microreactor as a new reactor to accelerate this process. Therefore, a semi-industrial pilot was investigated under different conditions for biodiesel production and optimizing the operating conditions. In order to optimize these conditions, the effect of important factors was studied including reaction temperature, catalyst concentration, volume ratio of oil-to-methanol and residence time on the purity of biodiesel produced through response surface methodology (RSM). After data analysis and optimizing the reaction of biodiesel production, the highest purity of produced biodiesel was obtained at reaction temperature of 65 °C, catalyst concentration of 8.1 wt%, oil/methanol volume ratio of 2.25:1 and residence time of 13.4 min which resulted in a biodiesel production with a purity of 97.45%. Based on the results, the use of microchannel can reduce the reaction time by the increase of mixing. Further, the cost of biodiesel production can be reduced using waste cooking oil and KOH/Clinoptilolite.

Towards sustainable biodiesel and chemical production: Multifunctional use of heterogeneous catalyst from littered Tectona grandis leaves

Waste biomass derived heterogeneous catalyst is an excellent alternative to chemically synthesized catalysts. In this work, calcined Tectona grandis leaves were proposed as an eco-friendly, renewable and low cost heterogeneous base catalyst. The prepared catalyst was examined by FTIR, XRD, XPS, SEM, EDX, TEM, TGA, BET and Hammett indicator test. The catalyst has an appealing nature towards various chemical transformations due to its basic surface sites provided by alkali and alkaline earth metals. The efficiency of the catalyst was successfully investigated by its application in biodiesel production. The products were confirmed by 1H and 13C NMR. 100% FAME conversion was attained using a catalyst loading of 2.5 wt% under optimized reaction parameters. The catalyst was further explored for Knoevenagel condensation reaction, in which it showed its effectiveness and recyclability towards the formation of benzylidenemalononitrile derivatives of aryl aldehydes. Thus, it is a potential ‘green catalyst’ derived from waste biomass without any addition of chemicals that can replace the industrial base catalysts used for biodiesel production and Knoevenagel reaction and makes the protocol environmentally benign.

Carica papaya stem: A source of versatile heterogeneous catalyst for biodiesel production and C–C bond formation

Development of solid mixed oxide catalyst from waste biomass is a scarcely studied area. Thus, present protocol aims to prepare an environmentally friendly, efficient, renewable and recyclable heterogeneous base catalyst from Carica papaya stem. The chemical and structural properties of the catalyst were examined by Fourier-transform infrared spectroscopy (FTIR), X-ray diffractograms (XRD), Scanning electron microscopy (SEM), Energy Dispersive X-ray spectrometry (EDX), Transmission Electron Microscopy (TEM) and Brunauer-Emmett-Teller (BET) analysis. The CO2-TPD and Hammett indicator test was conducted to determine the basicity of the prepared catalyst. The study revealed the presence of alkali and alkaline earth metals that provide the basic sites to facilitate transesterification reaction for biodiesel production and formation of benzylidenemalononitrile (BMN). The conversion of the waste cooking oil (WO) and Scenedesmus obliquus (SO) lipid to biodiesel was confirmed by the NMR and Gas chromatography Mass Spectroscopy (GC-MS) technique. Biodiesel conversions of 95.23% and 93.33% were achieved using 2 wt % catalyst loading under optimized reaction conditions for WO and SO respectively. Reusing the catalyst showed a slight drop in activity after 6 repeated uses. The reported catalyst has shown its potential as an alternative and cheaper green solid catalyst for biodiesel production and Knoevenagel reaction.

Palm biodiesel production using by heterogeneous catalyst based corn cobs

In this research, heterogeneous solid base catalysts were derived from corn cobs. the solid base catalyst was obtained which was then used for the production of palm oil biodiesel with a transesterification reaction. The catalyst prepared corn cobs with impregnation of NaOH then calcined temperature 400°C at 2 hours. The optimum conditions for the function of duration reaction time and catalyst amount obtained catalyst amount 3% at 60 minutes, temperature 65°C, ratio methanol to oil 12:1 obtained yield of biodiesel 93.10% while the function of reaction temperature and catalyst amount obtained catalyst amount 2.5%, ratio methanol to oil 12:1, at duration time is 60 minutes and temperature 60°C obtained yields 97.35%. The catalyst was easily separated from the reaction mixture by filtration and able to reuse for 2 times. The biodiesel product is specified with EN14214. Heterogeneous catalysts derived from corn cobs that show high-cost potential and produce easy ones as solid catalysts for the transesterification reaction of biodiesel production.

Flow-mode synthesis of biodiesel under simultaneous microwave–magnetic irradiation

Abstract In this study, aiming at optimization of a novel continuous biodiesel production system was developed by combining technologies based on microwaves and magnetic fields. Factors affecting microwave-assisted biodiesel (alkyl esters) production reaction were analyzed in this investigation. Studied factors included magnetic field intensity (0, 0.225 and 0.450 T), microwave power (400, 821, and 1181 W), percentages of KOH and NaOH catalysts at constant concentrations of 1 wt% (0, 50% and 100%), and percentages of ethanol and methanol at a constant molar ratio of 6:1 (0, 50% and 100%). Response Surface Methodology (RSM) was used to optimize the reaction conditions. RSM-based analysis indicated that, all independent parameters had significant effects on the reaction efficiency. Results of the investigations reveal that the largest effects on the conversion efficiency were due to type of alcohol and magnetic field intensity. The optimized conditions were found to be a magnetic field intensity of 0.331 T, a microwave power of 677.77 W, catalyst percentages of 30.35% and 69.65% for KOH and NaOH, respectively, and alcohol percentages of 80.47% and 19.53% for methanol and ethanol, respectively. Under the optimal conditions, yield of the reaction was 96.2%.

Sono-dispersion of MgO over Al-Ce-doped MCM-41 bifunctional nanocatalyst for one-step biodiesel production from acidic oil: Influence of ultrasound irradiation and Si/Ce molar ratio

MCM-41 is a mesoporous silicate with hydrophobic structure which is a good candidate as catalyst support in biodiesel production, with high specific area (more than 1100 m2/g) and high thermal stability. In this study the hydrothermal stability and acidic property of Al-MCM-41 were improved by addition of Ce element into its structure with various amounts of Si/Ce molar ratio. Then it was loaded by magnesium with two different procedures: customary impregnation and Sono-dispersion. The following techniques were utilized to characterize the synthesized nanocatalysts: EDX, FTIR, FESEM, DRS, BET and XRD. The catalytic performance of bifunctional nanocatalysts for biodiesel production from acidic oil was analysed, while four operational parameters were fixed as: catalyst charge equal to 5 wt%, reaction temperature equal to 70 °C, reaction duration equal to 6 h and methanol/oil molar ratio equal to 9. Generally, the obtained results revealed that the conversion and the quality of produced biodiesel were increased significantly by increasing Ce amount of catalysts up to Si/Ce = 25 and also the sonicated sample represented a better reusability compare to non-sonicated one. Among the prepared samples, Mg/ACM-U (Si/Ce = 25) achieved the maximum conversion and high reusability for biodiesel production reaction after fifth cycle.