Transesterification Of Coconut Oil Research Articles

Optimization of biodiesel production from coconut oil using a bifunctional catalyst derived from crab shell and coconut shell

The utilization of renewable biomass resources for biofuel production has gained widespread popularity as an effective means of converting waste into a valuable resource. This study investigated the optimization of biodiesel production from coconut oil (CO) using a bifunctional catalyst derived from crab shell and coconut shell. The catalyst underwent characterization through Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller. The acid precursor for the bio-based bifunctional catalyst was created from carbonized and sulfurized coconut shell, while the base precursor was obtained from calcined and KOH-treated crab shell. The experimental design was optimized using Box-Behnken design for the simultaneous esterification and transesterification of CO. Response surface methodology was employed to model and optimize the process. Under the determined ideal conditions, which included a methanol to oil ratio of 16.75:1, a 1.00% catalyst loading, a temperature of 58.19 °C, and a reaction time of 78.76 minutes, a CO methyl ester yield of 85.73% was achieved under experimental conditions. This yield closely aligned with the predicted range of 85.84% as per the model. The resulting methyl ester (biodiesel) obtained under these optimized conditions exhibited physicochemical properties well within the requirements specified by ASTM D6751 set by the International Organization of Standardization.

A Guinea Fowl Eggshells Derived Calcium Oxide Catalyst for Transesterification of Coconut Oil

The exponential rise in world population, the depletion of fossil fuels resources, and the severe environmental consequence of petroleum-based fuels have initiated an enormous search for renewable fuel as a substitute for petroleum fuel. In line with that, this study reports the use of a calcium oxide catalyst derived from waste guinea fowl eggshells in the transesterification of coconut oil for biodiesel production. The calcium oxide catalyst was prepared through the calcination of the eggshell at 950 oC for three hours and then characterized by Fourier Transform Infra-Red FTIR and basic back titration methods. The activity of the catalyst was evaluated in the transesterification of coconut oil with methanol by varying the reaction conditions to optimize the biodiesel conversion. The catalyst’s Fourier Transform Infra-Red (FTIR) analysis revealed a peak equivalent to the Ca-O bond at 665 cm-1, indicating eggshell conversion into CaO. This is justified by the appearance of a Ca(OH)2 peak around 3640 cm−1due to surface water attached to Ca2+. While to the basic back titration yielded a value of 2.933 mmol/g, indicating a high number of basic sites. Consequently, the activity test for the catalyst signified that one hour reaction time, 1:18 oil to methanol molar ratio, 1% catalyst loading, and 60 oC reaction temperature gave the best yield, with a conversion of 85.81%.

Green Synthesis, Characterization, and Catalytic Activity of Amine-multiwalled Carbon Nanotube for Biodiesel Production

An amine-functionalized multiwalled carbon nanotube (MWCNT) was prepared for use as a basic heterogeneous catalyst for the conversion of Cocos nucifera (coconut) oil and Hibiscus cannabinus (kenaf) oil to biodiesel. The 3-aminopropyltrimethoxysilane (3-APTMS) was chosen to form an amine-reactive surface to bind with hydroxyl (−OH) and carboxyl (−COOH) groups of oxidized MWCNT. Silanization took place using a green surface modification method in which supercritical carbon dioxide fluid was utilized under the following conditions: 55 °C, 9 MPa, and 1 h. The synthesized catalyst was characterized using Thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), Field emission scanning electron microscopy–energy dispersive x-ray (FESEM-EDX), Time-of-flight secondary ion mass spectrometry (TOF-SIMS), X-ray powder diffraction (XRD), and Brunauer–Emmett-Teller (BET). Transesterification of coconut oil using 10 wt% NH2-MWCNT catalyst (3 wt% APTMS), 12:1 molar ratio of methanol and oil at 63 °C for 1 h resulted in a >95% conversion. On the other hand, the same catalyst was used in the transesterification of kenaf oil, and formation of ammonium carboxylated salt was observed. The effects of temperature, pressure, and silane concentration on surface modification of MWCNT were evaluated in terms of the catalyst’s basic site density and fatty acid methyl ester conversion. The results indicate that reaction temperature and silane concentration had the most significant effects. Copyright © 2022 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Production of Magnesium Oxides from Raw Salt Solution Using Electrochemical Precipitation Method as a Heterogeneous Catalyst for Transesterification of Coconut Oil

This study was conducted to explore the production of magnesium oxide from raw salt solution using electrochemical precipitation, followed by calcination. Electrochemical precipitation was conducted by electrolysis of the salt solution using nickel rods as cathodes and graphite as anodes. Two sets of salt solutions were prepared: one set without pretreatment and another with BaCl2 pretreatment. The solutions were used to study the effect of salt concentration, potential, and electrolysis time. The representatives of the MgO produced were tested as catalysts for transesterification of coconut oil. The results indicate that optimum mass of precipitate was produced from 400 mg/L salt solution electrolyzed using 8 V for 60 min. Elemental analysis using X-Ray Fluorescence (XRF) revealed the presence of Mg as the main component of the precipitate, confirming the electrochemical conversion of Mg2+ into solid Mg(OH)2. The MgO with the purity of 74.23% and 88.87% was produced from non-pretreated and pretreated salt solution, respectively. The transesterification experiments indicate that the yield of 90% and 98% was achieved using the MgO produced from non-pretreated and pretreated salt solution, respectively.

Coating and incorporation of iron oxides into a magnetic-polymer composite to be used as lipase support for ester syntheses

The utilization of novel materials within the scope of biofuel synthesis has been represented as a significant step in the development of remarkable catalysts. The use of lipases in biodiesel production is often found as a cost-limiting step, as the operational expenditures in recovering such catalysts may lead to unfeasible market expectations. Herein, magnetic-polymer composites were evaluated as supports to immobilize commercial lipase, following the application in ethyl ester syntheses. A matrix of polysiloxane-polyvinyl alcohol (SiO2-PVA) was selected as the polymeric structure, following Fe3O4 and γFe2O3 coating and incorporation assays to the support backbone. Characterization of the produced catalyst support materials was performed via analysis of X-ray powder diffraction, pore size, Scanning electron microscopy, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. Burkholderia cepacia was then immobilized on the matrices, following transesterification of coconut oil with ethanol. The biodiesel samples generated were all within commercial standards, achieving conversion ester contents higher than 96.5%. The purified product samples (biodiesel) were essentially odorless and translucent appearance. Other properties such as density (873–876 kg m−3) and viscosity (3.76–3.93 mm2 s−1) meet the specifications required by the ASTM to be used as a biofuel.

PREPARATION OF INORGANIC CATALYST BASED HEMATITE (a-Fe2O3) COMPOUND EXTRACTED FROM ACEH IRON ORE MINERAL AND ITS CATALYTIC ACTIVITY ON TRANSESTERIFICATION OF COCONUT OIL

Hematite (Fe2O3) was successfully extracted from the Aceh iron ore mineral by precipitation method with employing sulphuricacid (H2SO4) as chemical agent. Furthermore, the extracted hematite was modified with sodium metal (K), namely it doped with NaOH of 5% and 10% (w/w), respectively. Based on the characterization results using XRD and SEM- EDS proved that modified catalyst (Na2O/Fe2O3) with their homogeneous size were resulted while the hematite (Fe2O3) particles was dopped withNaOH at its low concentration of (5% wt/wt), however while doping with the higher concentration of NaOH (10% w/w), agglomeration was taken place among the catalyst particles in which decreasing the surface area of the modified catalysts. Finally, the modified catalyst (Na2O/Fe2O3) was successfully applied as an inorganic catalyst on transesterification of coconut oil and methanol (T = 55 – 60oC, 2 h)for forming methyl esters asbiodiesel compounds.

PHYSICAL CHARACTERISTICS AND CATALYTIC ACTIVITY OF SULFATED SUGARCANE BAGASSE SILICA (SiO2/SO3 -H + ) FOR COCONUT OIL TRANSESTERIFICATION

In this study, silica extracted from sugarcane bagasse was converted into sulfated silica SiO2/SO3 -H+ by impregnating the silica with sulfuric acid to produce sulfated silica. The sulfated silica was then subjected to calcination at varied temperatures, and subsequently analyzed using Fourier Transform Infrared, Scanning Electron Microscope, and X-Ray Diffraction. The catalytic activity of the sulfated silica was tested for transesterification of coconut oil, and the reaction product was analyzed using Gas Chromatography-Mass Spectroscopy. The Fourier Transform Infrared results indicate the presence of absorption band at of 1126.43 cm-1, which is associated with S=O group, in sulfated silica spectrum, while in the original silica, this band is not detected. This difference between the spectra confirms that the silica was successfully converted into sulfated form. The silica and sulfated silica were found to have similar X-ray difractograms and fit very well with the X-ray difractogram of standard amorphous silica (JCPDS No. 29-0085), confirming the existence silica and sulfated silica as amorphous materials. Characterization using SEM shows the presence of irregular granules on the surface, which is in agreement with amorphous structure as seen by the XRD. Analysis of the transesterification product using GC-MS reveals that the product is composed of methyl esters of the fatty acids composing coconut oil commonly reported, suggesting that the sulfated silica produced possess catalytic activity as expected.

Production of dodecanedioic acid via biotransformation of low cost plant-oil derivatives using Candida tropicalis.

Dodecanedioic acid (DDA) is highly useful to the chemical industry as a versatile precursor for producing the polyamide nylon-6,12, which is used for many technical applications, such as heat and chemical-resistant sheaths. However, DDA synthesis has several drawbacks, such as high energy input and cost-intensive removal of by-products. Therefore, alternative bio-based production routes are required due to increasing industrial demand for green chemicals and renewable products. Candida tropicalis converts petrochemical-based n-dodecanes to the corresponding dicarboxylic acids by targeted functionalization. To increase sustainability of the DDA production process, we tested dodecanoic acid methyl ester, which can be easily obtained from transesterification of coconut oil, in whole-cell biotransformation by C. tropicalis. By modifying selected process parameters, a final DDA concentration of 66g/L was achieved using a highly reliable, small-scale bioreactor system. Crucial process development included a gradual pH shift, an optimized substrate feeding strategy, and monitoring the transcriptional profile.

Application of response surface methodology for optimizing transesterification of coconut oil

Application of response surface methodology for optimizing transesterification of coconut oil

Continuous enzymatic biodiesel production from coconut oil in two-stage packed-bed reactor incorporating an extracting column to remove glycerol formed as by-product.

The transesterification of coconut oil with ethanol catalyzed by Burkholderia cepacia lipase immobilized on polysiloxane-polyvinyl alcohol was performed in a continuous flow. The experimental design consisted of a two-stage packed-bed reactor incorporating a column with cationic resin (Lewatit GF 202) to remove the glycerol formed as by-product and the reactor performance was quantified for three different flow rates corresponding to space-times from 10 to 14h. The influence of space-time on the ethyl ester (FAEE) concentrations, yields and productivities was determined. The reactor operation was demonstrated for space-time of 14h attaining FAEE concentrations of 58.5±0.87wt%, FAEE yields of 97.3±1.9% and productivities of 41.6 ±1.0mgesterg medium (-1) h(-1). Biodiesel purified samples showed average kinematic viscosity values of 5.5±0.3mm(2)s(-1) that meet the criteria established by the American National Standard ASTM (D6751). The immobilized lipase was found to be stable regarding its morphological and catalytic characteristics, showing half-life time (t 1/2) around 1540h. The continuous packed-bed reactor connected in series with simultaneous glycerol removal has a great potential to attain high level of transesterification yields, raising biodiesel productivity.

The synthesis of biodiesel from coconut oil using novel Brønsted acidic ionic liquid as green catalyst

Four novel Brønsted acidic ionic liquids were synthesized and characterized by FT-IR, 1H NMR and 13C NMR for the first time. Their catalytic activities for the synthesis of biodiesel via the transesterification of coconut oil and methanol were investigated. Among all the tested ionic liquids, [CyN1,1PrSO3H][Tos] performed best, and its catalytic performance was systematically explored by orthogonal experiment based on the single factor experiment. The results show that the order of factors on the yield of biodiesel is reaction temperature, molar ratio of methanol/oil, catalyst dosage and reaction time. The maximum biodiesel yield of 98.7% was obtained under the optimal reaction conditions. There was no significant decrease of its catalytic activity after being reused for five successive cycles. The refined biodiesel meets the European biodiesel standard (EN 14214).

Transesterification of Coconut Oil Using Dimethyl Carbonate and TiO2/SiO2 Heterogeneous Catalyst

In this study, transesterification of coconut oil with dimethyl carbonate (DMC) for preparing biodiesel has been studied using TiO2/SiO2 as heterogeneous catalyst, with the main purpose to investigate the effect of molar ratio of DMC to oil. The product was analyzed by GC-MS to identify the fatty acid methyl esters (FAMEs) composting the biodiesel. The significant role of the DMC to oil ratio was observed in this study, in which the oil conversion was found to increase with increasing molar ratio of DMC : Oil, with the highest percent of conversion of 88.44%. The GC-MS analysis revealed the presence of methyl esters in accordance with the composition of coconut oil commonly reported. Formation of FAMEs was verified by 1H-NMR spectroscopic analysis, which also suggested that some of the fatty acids remain unconverted into biodiesel. The biodiesel produced was found to have kinematic viscosity of 2.4 mm2/S at 40 °C, flash point of 103 °C, and cetane number of 54.

Biodiesel production from coconut oil in supercritical methanol in the presence of cosolvent

The transesterification of coconut oil with supercritical methanol in the presence of cosolvent was carried out in a batch autoclave for production of biodiesel. The transesterification was found to be catalyzed by the surface of the autoclave. However, the catalytic activity of the autoclave dropped with great extent after a certain period of time. A 1.5 M oxalic acidic solution could be used to wash the surface to restore the catalytic activity of the autoclave. From the measured yields of biodiesel in a period of 20 min, ether was found to be the most effective cosolvent among eight cosolvents tested in this study. The effects of temperature, pressure, molar ratio of methanol to coconut oil, and molar ratio of methanol to cosolvent on methyl esters yield using ether as the cosolvent were examined. A temperature at least 30 °C higher than the critical temperature of methanol is essential for obtaining high biodiesel yield. The yield was also found to increase with increasing pressure, however, the extent of increase was reduced when the pressure was higher than 14 MPa. The most appropriate molar ratios of methanol to coconut oil and to ether were found to be 30/1/3. These molar ratios were observed invariant when CO 2 instead of ether was used as the cosolvent.