Methyl Ester Conversion Research Articles

Modeling the effects of ultrasound power and reactor dimension on the biodiesel production yield: Comparison of prediction abilities between response surface methodology (RSM) and adaptive neuro-fuzzy inference system (ANFIS)

Biodiesel is as an alternative petro-diesel fuel produced from the renewable resources. The use of novel technologies such as ultrasound technology for biodiesel production intensifies the reaction and reduces the process cost. The present study is aimed to evaluate and compare the prediction and simulating efficiency of the response surface methodology (RSM) and adaptive Neuro-fuzzy inference system (ANFIS) approaches for modeling the transesterification yield achieved in ultrasonic reactor. The influence of independent variables (reactor diameter, liquid height and ultrasound intensity) on the conversion of fatty acid methyl esters (FAME) was investigated by Box-Behnken design of RSM and two ANFIS approaches (hybrid and back-propagation optimization methods). All models were compared statistically based on the training and validation data set by the coefficient of determination (R2), root mean squares error (RMSE), mean absolute percentage error (MAPE), mean absolute error (MAE) and mean relative percent deviation (MRPD). The calculated R2 for RSM and two ANFIS models were 0.9669, 0.9812 and 0.9808, respectively. All models indicated good predictions, however, the ANFIS models were more precise compared to the RSM model, which proves that the ANFIS is a powerful tool for modeling and optimizing FAME production in ultrasound reactor.

Biodiesel from crude Pongamia pinnata oil under subcritical methanol conditions with calcium methoxide catalyst

ABSTRACTCrude Pongamia pinnata oil was subjected to a transesterification reaction with a calcium methoxide (Ca(OCH3)2) catalyst in subcritical methanol to obtain biodiesel. The variables affecting the methyl ester conversion were investigated. The obtained results were compared with non-catalyst and two-step reaction runs. The test results showed that the catalyst could improve the methyl ester conversion of biodiesel in subcritical methanol. A conversion rate of 99.50% was achieved with a 50:1 methanol-to-oil molar ratio, 1.0 %wt catalyst, and 2.0 h reaction time at 175°C. In addition, the important fuel properties of the biodiesel satisfied the biodiesel standards.

Biodiesel from corn germ oil catalytic and non-catalytic supercritical methanol transesterification

ABSTRACTTransesterifications of grain of corn oil samples in KOH catalytic and in supercritical methanol were studied without using any catalyst. Biodiesel, an alternative biodegradable diesel fuel, is derived from triglycerides by transesterification with methanol and ethanol. The transesterification reaction is affected by the molar ratio of glycerides to alcohol, catalysts, reaction temperature, reaction time and free fatty acids and water content of oils or fats. It was observed that increasing the reaction temperature, especially to supercritical temperatures, had a favorable influence on methyl ester (biodiesel) conversion. The molar ratio of methanol to corn germ oil is also one of the most important variables affecting the yield of methyl esters. Higher molar ratios result in greater ester production in a shorter time. In the transesterification, free fatty acids and water always produce negative effects, since the presence of free fatty acids and water causes soap formation, consumes catalysts, and reduces catalyst effectiveness, all of which result in a low conversion.

Economically viable production of biodiesel from a rural feedstock from eastern India, P. pinnata oil using a recyclable laboratory synthesized heterogeneous catalyst

Barium zirconate was synthesized by co-precipitation method and its feasibility as a heterogeneous catalyst for production of biodiesel (fatty acid methyl ester) was assessed. Fatty acid methyl ester (FAME) was synthesized through transesterification of karanja oil with methanol. Synthesized barium zirconate was characterized by Thermogravimetric analysis (TGA), Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffractometry (XRD), Energy dispersive X-ray spectroscopy (EDS), and Scanning Electron Microscope (SEM). Specific surface area and basicity of the catalyst were also deliberated. Catalyst characterization indicated formation of single phase of barium zirconate which was capable of catalyzing the transesterification of esterified karanja oil with methanol. Feedstock was characterized by Gas Chromatography Mass Spectrometry (GC–MS). Reaction conditions such as molar ratio (oil:methanol), catalyst concentration, temperature, time, stirring speed and catalyst reusability were optimized. Calcination temperature and time significantly affected the catalytic activity of the catalyst because of variation in availability of basic sites. FAME conversion of 98.79±0.5% was obtained at catalyst concentration of 1.0wt%, 1:27M ratio (oil:methanol), 65°C for a 3h contact time. The catalyst could be reused up to nine cycles and >65% fatty acid methyl ester conversion was sustained at ninth cycle. Glycerol obtained as a by-product was purified and analyzed by FTIR. Effect of catalyst on various feedstock at the same reaction conditions were studied. Physicochemical properties of karanja oil and respective methyl ester in comparison with petro diesel were also deliberated as per ASTM standards.

Effect of reaction parameters on the catalytic transesterification of cottonseed oil using silica sulfuric acid

ABSTRACTTransesterification of refined cottonseed oil was studied in the presence of silica sulfuric acid as a new heterogeneous solid acid catalyst to overcome the drawbacks of homogeneous alkali and acid catalysts. The effect of various reaction parameters, such as oil to methanol ratio, reaction temperature, reaction time, and catalyst amount, was investigated. The highest methyl ester conversion was obtained at 373 K using 5% catalyst amount and 1:20 methanol ratio within 8 h. Silica sulfuric acid was found to be a promising catalyst for cleaner biodiesel production without tedious post treatments for the product purification.

A review of cleaner intensification technologies in biodiesel production

Biodiesel is envisaged as environmentally benign fuel due to its unique properties, such as biodegradability, renewability and non-toxicity. Its utilisation leads to the reduction of sulphur oxide and greenhouse gas emissions as it produces quite lower amounts of carbon and sulphur based gases in comparison to conventional fossil fuels. This paper is a review of the recent achievements of the cleaner intensification technologies for biodiesel production. Merits and limitations of the cleaner intensification technologies have been discussed. Mechanical stirring via transesterification is the most common and extensively utilised for biodiesel production. It involves the conversion of oil to glycerol and acid alkyl ester while employing methanol. However, this process has an inherent drawback of mass transfer resistance resulting in a lower reaction rate and higher production cost. Intensification technologies have become more attractive to overcome these aforementioned problems. In a bid to increase the cost competitiveness of biodiesel production compared to diesel fuel, process intensification has been studied for numerous biodiesel processing technologies. Many researchers have resorted to several intensification technologies namely; microwave, ultrasonic cavitation and hydrodynamic cavitation reactor to eliminate the mass transfer resistance of immiscible reactants. Once the mass transfer resistance is reduced, it may lead to a shorter reaction time and lower energy consumptions compared to mechanical stirring. Recent studies reveal that microwave and ultrasonic cavitation techniques are not yet completely feasible for biodiesel production at industrial scale. On the other hand, it was found that hydrodynamic cavitation offers a number of advantages over other intensification technologies. It shows good performance with respect to product yield, reaction time, energy consumption and product quality. Furthermore, it exhibits a sustainable mean for energy recovery from renewable oils. It was concluded that more studies are needed to extend the existing information of hydrodynamic cavitation for the design of the plate geometry with respect to the methyl ester conversion. This will help to develop a sustainable and industrially viable route for energy recovery from renewable oils. Yield efficiency in relation to the method followed the order: hydrodynamic cavitation > microwave > ultrasonic cavitation > mechanical stirring.

Clam shell catalyst for continuous production of biodiesel

ABSTRACTContinuous flow transesterification of waste frying oil (WFO) with methanol for the biodiesel production was tested in a laboratory scale jacketed reactive distillation (RD) unit packed with clam shell based CaO as solid catalyst. The physiochemical properties of the clam shell catalysts were characterized by X-ray Diffraction (XRD), Brunauer–Emmett–Teller (BET), Scanning Electron Microscopy (SEM), and Energy Dispersive Atomic X-ray Spectrometry (EDAX). The effects of the reactant flow rate, methanol-to-oil ratio, and catalyst bed height were studied to obtain the maximum methyl ester conversion. Reboiler temperature of 65°C was maintained throughout the process for product purification and the system reached the steady state at 7 hr. The experimental results revealed that the jacketed RD system packed with clam shell based CaO showed high catalytic activity for continuous production of biodiesel and a maximum methyl ester conversion of 94.41% was obtained at a reactant flow rate of 0.2 mL/min, methanol/oil ratio of 6:1, and catalyst bed height of 180 mm.

Cleaner production of rubber seed oil methyl ester using a hydrodynamic cavitation: optimisation and parametric study

Producing sustainable biodiesel using non-edible feedstock via transesterification reaction assisted hydrodynamic cavitation technology is a viable way to offset fossil diesel usage. This technology has affirmative environmental impacts with lower energy consumption and the reaction time and offers a cleaner possibility. Methyl ester conversion has been observed at a different inlet pressure of 1–3.5 bar on different plate geometries in 50 L pilot hydrodynamic cavitation reactor. Orifice plate with 21 holes of 1 mm and inlet pressure of 3 bar found to be the optimal arrangement. Parametric optimisation used response surface methodology and found as alcohol to oil ratio of 6:1, catalyst loading of 1 wt.%, reaction time of 18 min and reaction temperature of 55 °C. About 5 fold shorter reaction time, 6.5 fold higher energy efficiency and 4.9 fold higher reaction rate constant using hydrodynamic cavitation compared to mechanical stirring. Hydrodynamic cavitation is concluded to be time saving and energy efficient process compared to mechanical stirring. This makes the process more environmental friendly using hydrodynamic cavitation. Most of the properties in rubber seed oil methyl ester were met the EN 14214 and ASTM D 6751 standards.

THE BIODIESEL PROCESSING FROM OIL OF YELLOWFIN TUNA [Thunnus albacares (Bonnaterre, 1788)] OFFAL USING ACID CATALYST

Biodiesel is one of the alternative fuels to meet the need of the diesel fuel in Indonesia. One of potential animal oil/fat to be utilized as biodiesel raw material is offal from yellowfin tuna. The objective of the study is to know the free fatty acid (FFA) levels of raw material, influence of the H2SO4 concentration as catalyst on biodiesel conversion, composition of the main Fatty acid compounds from biodiesel, and physical characteristics of biodiesel through esterification and transesterification reaction. In transesterification phase, the variabel is H2SO4 concentration 1.25 %, 1.50% and 1.75 % at 60 °C and 65 °C with oil to methanol molar ratio of 1:9. Based on experiment results, the know that: FFA content from oli of yellowfin tuna offal amounted to 2.33 %, the largest conversion of methyl ester from spectra of H-NMR, FT-IR, GC-MS and ASTM was produced from the treatment with 1.50 % H2SO4 at 65 °C, with an average yield of 89.09 % and the conversion value of methyl ester was 52.63 %. The main compounds of Fatty acids that formed biodiesel were palmatic acid (43.64 %) and oleic acid (32.08 %). The physical characteristics of biodiesel according to the national standards of Indonesia (NSI) were specific density of 0.8637 60/60 °F g mL–1kinematic viscosity of 2.555 mm2 s–1, pour point is -3 °C and cloud point of 25 °C, while flash point of 25 °C and water content of 0.20 % was not consistent with the SNI.

Biodiesel production from soybean and Jatropha oils using cesium impregnated sodium zirconate as a heterogeneous base catalyst

Cesium modified sodium zirconate (Cs-Na2ZrO3) was prepared by ionic exchange from sodium zirconate (Na2ZrO3), which was synthesized via a solid state reaction. Both ceramics, i.e., pristine Na2ZrO3 and the Cs-Na2ZrO3, were used as basic heterogeneous catalysts in biodiesel production. Soybean and Jatropha oils were used as triglyceride sources for transesterification reactions. Parameters, such as catalyst concentration (between 0.5 and 3 wt%), reaction time, different methanol/vegetable oil molar ratios, and temperature of the reaction, were evaluated. The cesium cation influence was evaluated from the basic transesterification reactivity. The results showed that the introduction of cesium significantly modified the catalytic activity in biodiesel production. Cs enhanced the reaction kinetics in obtaining biodiesel and reduced the reaction time in comparison with pristine Na2ZrO3. The results showed that Cs-Na2ZrO3 as a basic heterogeneous catalyst exhibited the best fatty acid methyl esters (FAME) conversion for soybean oil (98.8%) at 1 wt%, 30:1 methanol/oil ratio, 65 °C, and 15 min. The best conditions for Jatropha oil (90.8%) were 3 wt%, 15:1 methanol/oil ratio, 65 °C, and 1 h. The impregnation of Na2ZrO3 with cesium represents a very exciting alternative heterogeneous base catalyst for biodiesel production.

Preparation and Characterization of ZrO2 Polycrystalline Ceramic Foam Catalyst for Production of Biodiesel

Characteristics of ZrO2 polycrystalline ceramic foam catalyst including crystal structure, phase composition, and microstructure were analyzed by Py-IR, XRD, SEM, and BET. Effects of preparation conditions such as calcination temperature, calcination time, ZrO2 (catalyst matrix), Al2O3 (flux), TiO2 (stabilizer), NaHCO3 (low-temperature pore-forming agents), and NaCl (high-temperature pore-forming agents) on catalytic activity were investigated. The optimum composition of ZrO2 polycrystalline ceramic foam catalyst were optimized using response surface methodology (RSM) to be 88.47% ZrO2, 9.62% Al2O3, 3.31% TiO2, 10% NaHCO3, and 25% NaCl (compared with the standard number 100). After calcination at 1550°C for 120 min, fatty acid methyl ester conversion rates were substantially maintained at around 97.31%, The FAME content in the product oil exceeded 97% after five successive reuses of the catalyst. In addition, catalytic activity did not significantly fluctuate. The proposed catalyst presents a new type of solid catalyst with excellent catalytic activity and stability.

Utilization of palm fatty acid distillate in methyl esters preparation using [formula omitted]/TiO2–SiO2 as a solid acid catalyst

The use of by-products, particularly in the biodiesel industry, has gained much attention owing to their potential in countering higher feedstock costs. A low-value by-product of palm oil refining, the palm fatty acid distillate (PFAD), was utilized as a feedstock for biodiesel preparation with the aid of a solid acid catalyst, SO42−/TiO2–SiO2. A central composite design is applied to optimize the major influential manipulate variables. The analysis of variance identifies the methanol/PFAD molar ratio as having a dominant effect on methyl ester conversion, followed by catalyst amount and reaction time respectively. The utilization of PFAD with the aid of a solid acid catalyst results in 93.3 ± 1.02% conversion at the most optimized reaction conditions of 2.97 ± 0.04 wt% for the catalyst amount, 5.85 ± 0.14 methanol/PFAD molar ratio and 3.12 ± 0.14 h of reaction time.

Heteropoly acid coated ZnO nanocatalyst for Madhuca indica biodiesel synthesis

ABSTRACTBiodiesel is a biodegradable, nontoxic, and clean-burning fuel that can be made from vegetable oils or animal fats by transesterification reaction with short chain alcohols (typically methanol). Heteropoly acid coated ZnO nanocatalyst was prepared by co-precipitation method followed by calcination which was corroborated by transesterification of Madhuca indica oil with methanol. Synthesized nanocatalyst is able to catalyze the transesterification of fatty acids into fatty acid methyl esters conversion above 95% in 5 h. The synthesized biodiesel was analyzed by gas chromatography and mass spectrometry and proton-nuclear magnetic resonance spectrum to estimate the quantification of methyl esters and confirm the products. Heteropoly acid coated ZnO nanocatalyst and recovered catalysts were characterized by using Fourier transform-infrared spectroscopy, X-ray diffraction and field emission scanning electron microscope techniques.

Selective conversion of castor oil derived ricinoleic acid methyl ester into jet fuel

The selective conversion of ricinoleic acid methyl ester into jet fuel without carbon loss from fatty acid chains.

Vacuum Distilled Post Blend Crude Palm and Rubber Seed Oil Methyl Esters: Optimisation and Parametric Studies

Optimisation studies on post blended crude palm and rubber seed oil methyl esters were investigated. Post blended characteristics of methyl esters have been studied before and after vacuum distillation. The fuel properties of methyl esters met the international criteria of EN 14214 and ASTM D6751. Influential parameters that effects transesterification reaction have been analysed and optimised by response surface methodology. Catalyst loading and reaction temperature are the most influential variables which effects the methyl esters conversion. The optimised values were found to be alcohol to oil ratio of 6:1, catalyst loading of 1 wt%, reaction temperature of 65oC and reaction time of 2.5h.

Enhancing Effect of Calix[4]arene Amide Derivatives on Lipase Performance in Enantioselective Hydrolysis of Racemic Arylpropionic Acid Methyl Esters

Calix[4]arene amide derivatives were employed as new additives within the sol-gel encapsulation of lipase from Candida rugosa (CRL) to improve its catalytic properties. Evaluation of catalytic activity of the encapsulated lipases was acheived by enantioselective hydrolysis of both racemates, Naproxen methyl ester and 2-phenoxypropionic acid methyl ester, in aqueous buffer solution/isooctane reaction system. Results show that enantioselectivity was improved by using calix[4]arene amide derivatives-based encapsulated lipases. The reaction of naproxen methyl ester resulted in 47.6% conversion (x) in 24 h with 88.9% enantiomeric excess of substrate (ees), analogous to an enantioselectivity (E) value of 297 (E = 137 for the encapsulated free enzyme). The conversion of 2-phenoxypropionic acid methyl ester, obtained was 48.4% with E value of 327, enantiomeric excess of substrate (ees) of 92% for the reaction time of 1 h (E = 211 for the encapsulated free enzyme).

Improving the yield of Jatropha curcas's FAME through sol–gel derived meso-porous hydrotalcites

The conversion of fatty acid methyl ester (FAME) from triglycerides using heterogeneous catalysis has gained increasing interest due to the prospect of increased yield at reduced operating costs and reaction conditions. In this paper, meso-porous hydrotalcite was used to catalyze jatropha oil into FAME with relatively higher yield at atmospheric pressure and relatively low reaction temperature. The molar ratio of methanol to oil required was relatively low and the conversion was completed within few hours of reaction time. The reaction was promoted when moderate calcination temperature was applied, the disordered structure of the catalyst was maintained, counterbalance anions was removed, and phase transitions within the oxide lattice was induced. Despite the observed deactivation during successive reaction cycles due to adsorption of residual triglycerides, the catalyst performance was restored effectively by air-re-calcination.

Intensification of biodiesel synthesis from waste cooking oil (Palm Olein) in a Hydrodynamic Cavitation Reactor: Effect of operating parameters on methyl ester conversion

ABSTRACT This paper investigates a new route for intensification of methyl ester synthesis in Malaysia via alkali-catalysed transesterification of waste cooking oil derived from palm olein using a hydrodynamic cavitation reactor. The effects of the oil to methanol molar ratio (1:4–1:7), catalyst loading concentration (0.5–1.25 wt%) and reaction temperature (50–65 °C) have been investigated using an optimised plate with 21 holes of 1 mm diameter and an inlet pressure of 2 bar in a 50 L of hydrodynamic cavitation reactor assisted by a double diaphragm pump. Optimal conversion of 98.1% was achieved in 15 min in a hydrodynamic cavitation reactor with 1:6 molar ratio of oil to methanol, 1 wt% of catalyst and 60 °C of reaction temperature. It has been observed that a significant reduction in the optimum reaction time (about 6 fold) for transesterification from 90 min for mechanical stirring approach to 15 min for the hydrodynamic cavitation approach. Optimal yield efficiency of 12.50 × 10 −4 g/J was found using hydrodynamic cavitation and it was 8 fold higher than 1.5 × 10 −4 g/J when mechanical stirring was used.

Using lipase Candida rugosa as a catalyst for the biodiesel production from Tra fish (Pangasius hypophtalmus) oil

In this work, lipase from Candida rugosa (LCR) was used as a catalyst for the transesterification reaction of fish oil with methanol. The research process consists of three stages: determine the material properties and the activity of the enzyme from Candida rugosa, transeter of fish oil with methanol catalyzed by the enzyme lipase, evaluation indicators of the quality of biodiesel obtained. Fish oil contains 62% unsaturated fatty acid, acid value of 2.2 mg KOH/g. Activity and specific activity of enzyme were respectively 1064 U/mg enzyme and 2782 U/mg protein. Factors affecting the efficiency of conversion of fatty acid methyl esters - FAME were investigated: the molar ratio of methanol/fish oil, ratio of enzyme/fish oil, temperature reaction, pH reaction, concentration of buffer and reaction time. Yield of biodiesel conversion was 92.65% with optimal conditions: rate of methanol/fish oil was 4:1, the ratio of enzyme/substract was 2%, reaction temperature was 40°C, additional 10% buffer solution pH 7 with 96 hour response time. Products biodiesel obtained FAME components accounted for 98.94%; density at 15°C is 0.8816 g/ml; no free water and glycerine, consistent with the original standard biodiesel (B100) (TCVN 7717:2007). However, the acid value of 1.7 mg KOH products/g higher than the allowable value.

Kinetics of transesterification reaction using CAO/AL2O3 catalyst synthesized by sol‐gel method

Calcium oxide is one of the appropriate catalysts for biodiesel production. In this study, 40 wt. % CaO/Al2O3 catalyst was used. Transesterification reaction was performed in optimal condition presented in the previous study (0.05 molar nitric acid and gelation temperature of 70 °C) in a 250 mL two‐necked flask. All the experiments were carried out in the presence of soybean oil, methanol (methanol to oil molar ratio of 12:1), and catalyst concentration of 6 wt. %. Stirrer speed was set at 350 rpm. This study investigated the effects of reaction temperature and reaction time on produced biodiesel conversion. Methyl ester conversion changes in all temperatures and across different times indicated pseudo‐first order kinetic, so, first, the observed rate constant was obtained at various temperatures. Then, observed activation energy of soybean oil methanolysis in the presence of CaO/Al2O3 catalyst was determined. The results show that maximum errors of model are in primary times because methanol is insoluble in soybean oil. At the other times and by biodiesel and glycerol production, there was increased solubility of methanol in oil. The methyl esters production rate is related to diffusion of methanol in oil film and reaction rate constants which are calculated these constants.