Soybean Oil Biodiesel Research Articles

Ethyl biodiesel production from crude soybean oil using enzymatic degumming-transesterification associated process

Brazil is one of the largest soybean producers in the world. Biodiesel production in Brazil (specially soybean oil biodiesel) has been growing every year and demanding more effective and sustainable technologies, which is the case of enzymatic processes. Enzymatic degumming could be an alternative to provide better quality products, before biodiesel production but also, in a one reaction step as a proposal to reduce time and costs. Therefore, this work was aimed at evaluating enzymatic degumming (previously optimized) of crude soybean oil using a phospholipase cocktail associated with transesterification using lipase from Aspergillus oryzae for ethyl biodiesel production. For this, transesterification was optimized for ethanol:oil (E:O) ratio, water and lipase % through a central composite rotatable design (CCRD). Optimal conditions were used to evaluate two degumming-transesterification associated processes: i) a one-pot reaction (OPR) where degumming and transesterification were performed at the same reactor; and ii) a two-pot reaction (TPR) where oil was first degummed, followed by transesterification. The optimal transesterification condition were achieved for E:O = 4.48:1, water = 3.41 % and lipase = 2.43 %, where 97 % fatty acid ethyl esters (FAEE) were obtained. Both OPR and TPR provided biodiesels with FAEE > 94 %: TPR was the best with 97.5 % and 99.98 % before and after biodiesel purification. Mineral elements (including phosphorus) and other impurities (anions) were low, and within quality standards. Glycerol produced also presented very low content of impurities which is quite advantageous. Although lipase achieves good conversion to FAEE (95.7 ± 0.29 %) using crude oil (Control), the final biodiesel carries many impurities (P=80.07 ± 0.1 mg/kg), thus requiring subsequent biodiesel purification steps. In addition, the high impurity content generates a biodiesel that does not comply with ANP legislative standards, P<10 mg/kg. The use of enzymatic degumming in the biodiesel production process generates a biodiesel with low impurities and higher final quality, in addition to being a process that generates less effluent. Enzymatic degumming was essential for obtaining high quality biodiesel and its association with transesterification showed to be a great option for decreasing time and costs for biodiesel production.

Blending biomass-based liquid biofuels for a circular economy: Measuring and predicting density for biodiesel and hydrocarbon mixtures at high pressures and temperatures by machine learning approach

Circular economy is an efficient approach to deal with the rapidly increasing demand for energy and its environmental impact. It involves switching to renewable and sustainable energy sources. By providing an alternative to traditional energy resources, biodiesel promotes a circular economy paradigm that embraces renewable energies rather than fossil fuels. As an alternative to fossil fuels, liquid biodiesel helps to improve energy efficiency and reduce pollution. Furthermore, blending biodiesel has proven to be economically and environmentally viable. Knowledge of the thermodynamic properties of biodiesel, such as densities and coefficients of expansivity and compressibility, plays an important role in understanding and determining the behavior of the fuel under different operating conditions. The blend densities of Soybean Oil Biodiesel (SOB) with hexane and Waste Cooking Oil Biodiesel (WCOB) with heptane in four volume ratios were experimentally studied. An Anton Paar vibrating tube densimeter HPM DMA has been used for accurate measurements of densities of the biofuels and their blends. Density measurements were performed at temperatures ranging from 298.15 K to 393.15 K, and pressures between 0.1 MPa and 140 MPa. This work also aims to develop accurate prediction models of the properties of biodiesel blends under various conditions, such as changes in temperature and pressure, which are essential for optimizing energy production processes and engine performance. In this context, the dataset was first investigated with Tait Equation of State (Eos) to determine thermodynamic parameters which including isothermal compressibility and isobaric expansivity. It showed generally low standard deviations. Furthermore, these new experimental densities were also modeled with Artificial Neural Network (ANN) as a machine learning method. This paper models proved that the machine learning method is a suitable tool to model the thermo-physical characteristics of liquid fuels. The findings of this study have the potential to provide valuable guidance to engine engineering applications developers regarding operating conditions and the selection of suitable biodiesel for their system.

Production of waste soybean oil biodiesel with various catalysts, and the catalyst role on the CI engine behaviors

The soybean oil wastes are disposed of after being used multiple times (maximum utilization) in the various food processing industries. Disposal of such waste are harmful to the environment and human. Hence, this investigation aims to use such wastes are used for producing alternate fuels for diesel engines. The biodiesel produced from the soybean waste cooking oil by transesterification process with different hybrid catalysts such as the membrane of Poly-acrylonitrile nanofibrous (MPANF), Alkyl-celite (AC), Iron oxide (IO-II) and Ni-doped ZnO (NDZ). The transesterification process variables like flow velocities varied from 0.3 to 1.5 mL/min and the reaction time varied from 15 to 75 h. The influence of such variables was investigated. The best two yields of waste soybean oil (BDWSBO) with the use of IO-II and AC catalysts respectively at 1.5 mL/min of flow rate at a 75-h reaction time, were considered for preparing further blends with diesel of 25 vol% and 50 vol% (Total 4 fuel varieties other than plain diesel). The test results revealed that a blend of 25 % diesel fuel with 75 % IO-II -used BDWSBO has 30.05 % BTE, which is nearer to diesel fuel (30.81 %). This blend has 17.96 % lesser smoke opacity than diesel fuel. Therefore, this 25 % diesel fuel with 75 % IO-II -used BDWSBO blend is recommended for higher production biodiesel and application in the IC engine as an alternate fuel without any modifications.

Zr-modified desilicated ZSM-5 catalysts as highly active and recyclable catalysts for production of biodiesel from soybean oil: Insight into improved catalyst properties, acidity and dispersion through desilication

Bio-based fuels, such as biodiesel, have recently gained attention due to concern about ever-increasing energy consumption and global warming. Solid catalysts are key materials in the production of green biodiesel. The use of solid catalysts in the production of biodiesel can lower the cost of the separation and thus reduce biodiesel costs. In the present study, zeolite-supported ZrO2 catalyst (ZrO2/ZSM-5) and a series of desilicated zeolite-supported ZrO2 catalyst [ZrO2/ZSM-5(0.1–0.3 M)] were successfully synthesized by impregnation method and used as new catalysts for the production of soybean oil biodiesel through transesterification. Desilication at various sodium hydroxide concentrations enhances the external surface area and mesoporous volume, without jeopardizing crystallinity or microporosity of the catalysts. The synthesized catalysts were characterized via X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), pyridine-FTIR, scanning electron microscopy, TEM, XRF, TGA and nitrogen adsorption-desorption. Nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC–MS) were used to characterize the biodiesel that was produced. The as-prepared ZrO2/ZSM-5(0.2 M) catalyst exhibited better catalytic activity in the transesterification of soybean oil with methanol, compared to ZrO2/ZSM-5 catalyst, due to large pore volume, high surface area, and high dispersion of ZrO2 on the desilicated zeolite support with improved acidity and high number of active sites. A biodiesel conversion of 90.1% and 97.84% were obtained for zeolite-supported ZrO2 catalyst and desilicated zeolite-supported ZrO2 catalyst, respectively, under optimum reaction conditions of 1.0 wt% catalyst loading, 1:16 soybean oil/methanol molar ratio at 200 °C in 4 h reaction time. Moreover, the desilicated zeolite-supported ZrO2 catalyst exhibited excellent stability and re-usability giving a biodiesel conversion of 93.8% after three cycles of reuse.

Terminalia arjuna bark – A highly efficient renewable heterogeneous base catalyst for biodiesel production

In agreement with the necessity for green synthesis, the present study elevates the feasibility of exploiting Terminalia arjuna bark calcined ash (TABCA) - a highly functional renewable heterogeneous alkaline catalyst for the cost-effective synthesis of fuel-grade fatty acid methyl esters (FAME) by soybean oil (SO) transesterification under microwave irradiation. The mesoporous nature, significant surface area, and an extreme degree of basicity owing to the presence of CaO, MgO, K2O, SiO2, Na2O, and P2O5 effectively facilitate the SO conversion. Under the optimal conditions of 24:1 M ratio of methanol: SO, 8 wt % catalyst concentration, 80 °C temperature and time period of 60 min, microwave irradiation exhibits highest biodiesel yield (99.2 ± 0.6%) and improved selectivity (100%). Likewise, FAME content in the biodiesel was found to be 99.01% from 1H NMR. The produced SO biodiesel meets the ASTM D6751 and EN 14214 standard requirements, making it compatible in existing engines. In addition, the mesoporous TABCA catalyst showed high stability for five consecutive transesterification reactions which yielded 80 ± 0.8% biodiesel without additional treatments.

Prediction of the Engine Performance and Emission Characteristics of Glycine Max Biodiesel Blends With Nanoadditives and Hydrogen

Abstract This study investigates the Glycine max (soybean oil) biodiesel with hydrogen along with MgO nanoadditives on compression ignition engines. A series of tests were conducted at various loading conditions in a water-cooled, single-cylinder, constant-speed engine. The biodiesel-blended soya oil was used as the primary fuel, and hydrogen was added at a constant volume of 25 LPM. Additionally, MgO nanoparticles were dispersed to the blends at concentrations of 50 ppm. In this study, it was found that the addition of hydrogen to the compression ignition (CI) engine resulted in an increase in combustion performance. In addition, hydrogen and oxygen molecules significantly reduced the exhaust gas temperature and brake-specific fuel consumption of biodiesel samples. An increase in nanoparticle concentration resulted in a reduction in emissions of pollutants such CO2, CO, and HC. Inclusion of the hydrogen in the combustion chamber reduces the carbon content burned. Further, the availability of extra molecules in the MgO aids the fuel to reach higher combustion rates. At higher load conditions, biodiesel blends showed a slight decrease in NOx emissions. Overall, from the findings, it is clear that hydrogen addition and nanoparticles enhanced emission and combustion process, which is attributed due to the increase in hydrogen content in the fuel.

Comparison of the Engine Performance of Soybean Oil Biodiesel Emulsions Prepared by Phase Inversion Temperature and Mechanical Homogenization Methods

The engine performance and emission characteristics of burning emulsions of soybean oil biodiesel in a compression-ignition diesel engine prepared through the phase inversion temperature method were compared with those of neat soybean oil biodiesel and the emulsion prepared by the mechanical homogenization method. The engine torque was set constantly at 98 N·m with varying engine speeds. The experimental results show that the emulsion prepared by the method of phase inversion temperature had higher O2 and NOx emissions, a higher excess air ratio, a higher exhaust gas temperature, and a higher brake fuel conversion efficiency than the emulsion prepared by the mechanical homogenization method, which had lower CO and CO2 emissions, a lower equivalence ratio, and lower brake-specific fuel consumption. While the neat soybean oil biodiesel was found to have the lowest fuel consumption rate, brake-specific fuel consumption, and CO and CO2 emissions, it had the highest exhaust gas temperature and brake fuel conversion efficiency, NOx and O2 emissions, and excess air ratio among those three fuels. Therefore, the phase inversion temperature method is considered promising for preparing fuel emulsions as an alternative to petro-derived diesel for compression-ignition engines.

Evaluation of Oxidative Stability and Kinetic Parameters of the Cottonseed and Soybean Biodiesels by Rancimat and Differential Scanning Calorimetry Techniques

In this study, the oxidative stability of the cottonseed oil biodiesel (CB) and soybean oil biodiesel (SB) was investigated by two methodologies, Rancimat and Differential Scanning Calorimetry (DSC), using samples fresh and aged (mid-term storage condition (100 days)). The biodiesel samples were synthesized by transesterification and characterized by specific mass, kinematic viscosity, acidity value, ester content, viscosity index, and peroxide value. The activation energy (&lt;em&gt;E&lt;sub&gt;a&lt;/sub&gt;&lt;/em&gt;), Arrhenius pre-exponential factor (&lt;em&gt;Z&lt;/em&gt;), reaction order (&lt;em&gt;n&lt;/em&gt;), and reaction rate at constant temperature (&lt;em&gt;k&lt;/em&gt;(T)) were calculated by Borchardt and Daniels method. The results showed that oxidation affected the physicochemical properties of the biodiesel samples, especially, acidity (mg KOH/g), peroxide value (meq/1000 g), and induction period, with a decrease of around 55% for CB and 29% for SB. For kinetic parameters, the k(T) of both aged samples presented the highest values, with an increase of around 314% for SB. It was also observed that the rate constants increased with decreasing values of the induction period, in agreement with the current literature. According to the evaluation, the Borchardt and Daniels method can be recommended for a quick assessment of the biodiesel oxidation kinetic parameters.

Effects of the Degree of Unsaturation of Fatty Acid Esters on Engine Performance and Emission Characteristics

Biodiesel is considered an environmentally friendly alternative to petro-derived diesel. The cetane number indicates the degree of difficulty in the compression-ignition of liquid fuel-powered engines. The allylic position equivalent (APE), which represents the unsaturated degree of fatty acid esters, was one of the key parameters for the cetane number of biodiesel. Due to the significant attributes of APE for biodiesel properties, the impact of APE on engine performance and emission characteristics was investigated in this study. The engine characteristics could be improved by adjusting the biodiesel fuel structure accordingly. A four-stroke and four-cylinder diesel engine accompanied by an engine dynamometer and a gas analyzer were used to derive the optimum blending ratio of the two biodiesels from soybean oil and waste cooking oil. Three fuel samples composed of various proportions of those two biodiesels and ultra-low sulfur diesel (ULSD) were prepared. The amounts of saturated fatty acids and mono-unsaturated fatty acids of the biodiesel made from waste cooking oil were significantly higher than those of the soybean-oil biodiesel by 9.92 wt. % and 28.54 wt. %, respectively. This caused a higher APE of the soybean-oil biodiesel than that of the biodiesel from waste cooking oil. The APE II biodiesel appeared to have the highest APE value (80.68) among those fuel samples. When the engine speed was increased to 1600 rpm, in comparison with the ULSD sample, the APE II biodiesel sample was observed to have lower CO and O2 emissions and engine thermal efficiency by 15.66%, 0.6%, and 9.3%, while having higher CO2 and NOx emissions, exhaust gas temperature, and brake-specific fuel consumption (BSFC) by 2.56%, 13.8%, 8.9 °C, and 16.67%, respectively. Hence, the engine performance and emission characteristics could be enhanced by adequately adjusting the degree of unsaturation of fatty acid esters represented by the APE of biodiesel.

Partial Hydrogenation of Soybean and Waste Cooking Oil Biodiesel over Recyclable-Polymer-Supported Pd and Ni Nanoparticles

Biodiesel obtained through the transesterification in methanol of vegetable oils, such as soybean oil (SO) and waste cooking oil (WCO), cannot be used as a biofuel for automotive applications due to the presence of polyunsaturated fatty esters, which have a detrimental effect on oxidation stability (OS). A method of upgrading this material is the catalytic partial hydrogenation of the fatty acid methyl ester (FAME) mixture. The target molecule of the partial hydrogenation reaction is monounsaturated methyl oleate (C18:1), which represents a good compromise between OS and the cold filter plugging point (CFPP) value, which becomes too high if the biodiesel consists of unsaturated fatty esters only. In the present work, polymer-supported palladium (Pd-pol) and nickel (Ni-pol) nanoparticles were separately tested as catalysts for upgrading SO and WCO biodiesels under mild conditions (room temperature for Pd-pol and T = 100 °C for Ni-pol) using dihydrogen (p = 10 bar) as the reductant. Both catalysts were obtained through co-polymerization of the metal containing monomer M(AAEMA)2 (M = Pd, Ni; AEEMA− = deprotonated form of 2-(acetoacetoxy)ethyl methacrylate)) with co-monomers (ethyl methacrylate for Pd and N,N-dimethylacrilamide for Ni) and cross-linkers (ethylene glycol dimethacrylate for Pd and N,N’-methylene bis-acrylamide for Ni), followed by reduction. The Pd-pol system became very active in the hydrogenation of C=C double bonds, but poorly selective towards the desirable C18:1 product. The Ni-pol catalyst was less active than Pd-pol, but very selective towards the mono-unsaturated product. Recyclability tests demonstrated that the Ni-based system retained its activity and selectivity with both the SO and WCO substrates for at least five subsequent runs, thus representing an opportunity for waste biomass valorization.

PRODUCTION CHARACTERIZATION AND TESTING OF SOYBEAN BIODIESEL IN A DIESEL CYCLE ENGINE

The characteristics of the biodiesel produced by the transesterification reaction of soybean oil with anhydrous ethanol, catalyzed by sodium hydroxide and its thermo-oxidative stability, were investigated by thermal analysis and viscosity. It was analyzed density at 20 °C, sulfur content, cetane number, carbon residue, iodine index, acidity, sulphated ash, the total content of glycerin and unreacted fatty acids. The synthesis of biodiesel via ethanolic processed in a Pyrex glass reactor with 2/1 molar ratio triglyceride/anhy-drous ethanol and 1% of catalyst, 60 °C. After the reaction, the phases were separated and glycerin was removed. The biodiesel was washed with 0.1M HCl solution, at ~ 70 oC for neutralization. The physicochemical analysis, all parameters for biodiesel met the requirements of the ANP Technical Standards. From the produced biodiesel, binary mixtures were made with diesel in the proportions of 2, 5, 10, 15, 20 and 30%. The objective was to study the behavior of mixtures in a diesel cycle engine coupled to a dynamometer of Eddy Current. In this study of burning biodiesel blends in diesel engine were analyzed and compared with pure diesel parameters: consumption, efficiency, performance, torque and power. The results showed that the mixtures had very similar properties and performance to pure diesel by mixing 20%. To the mixture with 30% there has been a significant drop in torque and power and slight increase in consumption. Thus, it was shown that soybean oil biodiesel, mixtures of 2% to 30%, is applicable as an alternative fuel aptly, for the diesel cycle engines, because it is a renewable and environmentally friendly fuel.

Tangerine peel ashes applied as green catalyst: a biorefinery‐based approach for biodiesel production

AbstractIn this research, a greener heterogeneous catalyst (named TPC) was obtained from ‘Ponkan’ tangerine (Citrus reticulata Blanco) peel ashes. TPC was efficient for biodiesel production through the methyl route using refined soybean oil and waste cooking oil as raw materials in a biorefinery‐based approach. Eight catalyst samples were prepared via calcination of the ashes at 700 °C (TPC7), 800 °C (TPC8) and 900 °C (TPC9), and blends of TPC7 with CaCO3 and K2CO3. All the catalysts were employed in preliminary tests for the transesterification reactions. A set of characterization techniques such as Fourier transform infrared and spectroscopy, X‐ray diffractometry, X‐ray fluorescence, field emission gun scanning electron microscopy, energy‐dispersive X‐ray, CO2‐desorption at programmed temperature, thermogravimetric analysis/derivative thermogravimetry (DTG), N2 adsorption–desorption isotherms, and the Hammett basicity test were performed for catalysts assessment. The X‐ray diffractometry patterns showed peaks associated with characteristic phases of K2CO3, CaCO3, K2Ca(CO3)2, MgO and CaO, confirmed by Fourier transform infrared spectroscopy spectroscopy and X‐ray fluorescence. CO2‐desorption at programmed temperature data demonstrated the presence of basic sites in the TPC catalysts. The experimental evaluation by response surface methodology using the D‐Optimal design showed that the reaction time effect (F = 19.04, P‐value = 0.0005) and its interaction with the molar ratio effect are the most significant parameters to improve the yield of refined soybean oil biodiesel. The selected reaction conditions promoted a methyl ester conversion higher than 92%, as calculated from 1H NMR data. Furthermore, the production of waste cooking oil biodiesel was effective using TPC7 and TPC8 catalysts, allowing a sustainable and economic feasibility process. © 2021 Society of Chemical Industry and John Wiley &amp; Sons, Ltd

Application of Psidium guajava L. leaf extract as a green corrosion inhibitor in biodiesel: Biofilm formation and encrustation

In this paper guava leaf extract was used as antioxidant additive to biodiesel in order to verify its corrosive properties. The study of the copper exposed to soybean oil biodiesel was carried out at room temperature for 2520 h and at 60 °C for 1440 h. Scanning Electron Microscopy/ Dispersive Energy Spectroscopy (SEM/EDS) and X-ray Diffraction (XRD) results show less wear and oxidation of the copper plates immersed in biodiesel with the additive indicating that it is better protected from corrosive processes presenting an efficiency of inhibition (Ei) of 55.37 % and 21.11 % at room temperature and 60 °C, respectively. At room temperature the effect of using the additive is observed with the naked eye and confirmed by the SEM in which it is verified that the specimen was less attacked compared to neat biodiesel. However at 60 °C the use of the additive showed a significant improvement in the vaporization of biodiesel in the region that was not exposed to the fuel. These behaviors result in less formation of corrosion products on the surface of the copper that was exposed to additive biodiesel according to XRD analysis. The observed positive results are justified due to the physisorption of antioxidant compounds found in the additive on the metallic surface with formation of a protective biofilm on the metal surface.

Evaluation of the corrosion inhibitory effect of the ecofriendily additive of Terminalia Catappa leaf extract added to soybean oil biodiesel in contact with zinc and carbon steel 1020

Natural antioxidants have been studied and is know to bring characteristics such as sustainability and environmental compatibility to the process. The tropical almond (Terminalia catappa) leaf extract was used as antioxidant additive to the soybean oil biodiesel in order to verify the improvement of its corrosive property in contact with zinc and carbon steel 1020. Gravimetric test according to ASTM G1-03 and G31 standards was used at room temperature for 2520 h and 60 °C for 1440 h. The morphology of the metal plates was analyzed by Scanning Electron Microscopy/Dispersive Energy Spectroscopy, X-ray Diffraction and the biodiesel through acidity index, Fourier Transformed Infrared Absorption Spectroscopy. At the end of the tests the carbon steel 1020 suffered no corrosion. However, for zinc mild corrosion was observed at room temperature and accentuated at 60 °C (efficiency of inhibition of 78.41% and 8.15%, respectively; increase activation energy in 31%). Interesting result is that at room temperature a greenish protective layer was observed in the region exposed to fuel from antioxidant components present in the plant for both metals. The results of this work indicate that the plant extract can be used as an anticorrosive additive in the two conditions studied.

Effect Soursop Leaf Extract For Oxidation Stability Of Palm Oil Biodiesel and Soybean Oil Biodiesel

Biodiesel is one of the alternative energy sources for diesel oil substitutes. However, the unsaturated fatty acid contains in vegetable oils leads to the poor oxidation stability of biodiesel. One of the potential methods used to prevent or delay the oxidation reaction is the addition of antioxidants because the process is much more straightforward and efficient. Soursop leaf was reported to have the potential to be used as a natural antioxidant. Soursop leaf extracted using solvent n-hexane and ethyl acetate. The crude extract with concentration 0, 100, 200, 300, 400 ppm tested to palm oil and soybean oil biodiesel. Oxidation stability of biodiesel analyzed using the 873 Rancimat instrument biodiesel. The results show that a concentration of 100 ppm soursop leaf extracted with both n-hexane and ethyl acetate increased the Induction Period (IP) of palm oil biodiesel more than 16 h. This result meets the SNI biodiesel requirements in which the IP minimum for biodiesel is eighth.

Estudio de desempeño y emisiones en motores diesel operando con biodiesel a partir de aceite de soja y emulsiones de agua.

This study evaluates the influence on the combustion process, fuel consumption, and polluting emissions in a diesel engine, which operates with biodiesel from soybean oil and water emulsions with percentages of 4% and 8%. For this study, a stationary diesel engine operating at four different torque conditions and a fixed rotation speed of 3400 rpm is used. Test fuels are diesel, soybean oil biodiesel, and SB4W and SB8W water emulsions. The results indicate that SB4W and SB8W cause a 6% reduction in calorific value and an 18% and 1% increase in viscosity and density. However, the presence of water in biodiesel can help reduce engine BSFC by 8%. The SB4W and SB8W allow a 23% reduction in NOx emissions. With the use of SB4W fuel, a reduction of 16%, 29%, and 14% in CO, HC, and smoke opacity is obtained compared to soybean oil biodiesel. The maximum inclusion of 8% water in soybean oil biodiesel is recommended since a higher percentage can cause the presence of incomplete combustions.

Determination of total phosphorus in biodiesel by ion chromatography

Phosphorus content in biodiesel is an important parameter for evaluating its quality. In this paper, the total amount of phosphorus in biodiesel was determined by Ion Chromatography (IC) with on-line matrix elimination function. An effective and safe sample pretreatment method and IC quantification method were adopted. The method has good linear correlation (r = 0.9998), low detection limit (Cmin = 0.007 mg L−1) and reasonable reproducibility. By measuring the residual carbon of biodiesel ashing products at different temperature points as an index of ashing degree, phosphate from biodiesel ashing products at different temperature points was determined by IC; the optimum ashing temperature was 680 °C. At 680 °C, the amount of phosphorus in Jatropha curcas biodiesel was determined by both IC and ICP-OES; the measured phosphorus content was 13.53 mg·kg−1 and 11.25 mg·kg−1, respectively, and exceeded the national standard of 10 mg·kg−1. In addition, the phosphorus content of soybean oil biodiesel was tested by IC at different ashing temperatures. Those results showed that at 680 °C, the biodiesel phosphorus content in soybean oil was 5.41 mg·kg−1, lower than the 10 mg·kg−1 stipulated by ASTM D 6751 and GB 25199, but higher than the 4 mg·kg−1 stipulated by EN14214.

Biodiesel feedstocks selection strategies based on economic, technical, and sustainable aspects

The interest in sustainable energy sources such as biodiesel is growing due to unpredictable fossil fuel prices, depletion of their origins, inconsistent supply, geopolitical instability, and conflicts of fuel/oil-producing countries, global politics, and sanctions. The selection of the right biodiesel feedstocks is the first step of mass biodiesel production. This paper is aimed at defining the best possible biodiesel feedstocks using various multiple criteria decision analysis (MCDA) processes. Several facets that can effect on the biodiesel feedstocks selection process are economic, technical, environmental, and social aspects. This study concentrated on fifteen ‘criteria’ based on the economic aspect (cost of biodiesel production), technical aspects (physicochemical properties and structural composition (fatty acid) of biodiesel feedstocks), and environmental aspects (sustainable land usage for crop production) for the selection process. Sixteen most popular biodiesel feedstocks, namely Palm, Soybean, Sunflower, Moringa, Jatropha, Pongamia, Mustard, Coconut, Tallow, Peanut, Corn, Cottonseed, Ricebran, Beauty leaf, Rapeseed and waste cooking oil biodiesel were investigated as ‘alternatives’ in this analysis. For ‘weight’ determination of each criterion, five weighting methods in percentage, namely EQUAL, CRITIC, ENTROPY, Analytical hierarchical process (AHP), and Fuzzy Analytical Hierarchical Process (FAHP) were used. Four MCDA processes, namely PROMETHEE Graphical Analysis for Interactive Assistance (GAIA), Weighted sum method (WSM), Weighted product method (WPM), and Technique for order preference by similarity to ideal solution (TOPSIS) were implemented for this investigation. The findings indicate that Coconut rated best and Soybean was regarded as the worst feedstock among those alternatives.

Methylic and ethylic biodiesel production from crambe oil (Crambe abyssinica): New aspects for yield and oxidative stability

Biodiesel is a fuel comprised of mono-alkyl esters of long-chain fatty acids derived from vegetable oils or animal fats. Biodiesel is designated B100 and is regarded as the major substitute for fossil diesel. Crambe abyssinica, a native plant from Ethiopia, has great potential for biodiesel production due to its higher calorific value and oxidative stability as compared to soybean oil biodiesel. Compared to fossil diesel, C. abyssinica oil biodiesel emits significantly less CO2 without efficiency loss. However, its crude oil only provides good results if it undergoes supercritical transesterification. Here, we aimed to produce ethyl and methyl esters from crambe oil under ambient conditions. Initially, we tested two methods to degum crambe oil: aqueous degumming and acid degumming. We subjected the degummed oil to transesterification through the methylic or the ethylic route, catalyzed by KOH. The methyl esters of the biodiesel obtained by esterification of crambe oil submitted to acid degumming had higher oxidative stability as compared to the methyl esters of the biodiesel obtained from crambe oil subjected to aqueous degumming: 15.7 h and 10.7 h, respectively, but the yield was lower: 70% vs. 80%, respectively. The ethyl esters of the biodiesel obtained from crambe oil submitted to aqueous degumming provided the highest yield and oxidative stability: 65% and 8.5 h, respectively. We also evaluated the oxidative stability of blends consisting of crambe oil methylic or ethylic biodiesel and soybean oil biodiesel.

Surface Effects on Engine Materials of Mineral Oil Dilution With Methyl Esters and Biodiesels

During ordinary internal-combustion engine operation, biodiesels partially mix in the engine-oil, leading to increased surface degradation, as premature wear. Biodiesels are blends of methyl esters as main components, which are dependent on the source feedstock and may lead to different surface effects on engine materials. In this preliminary study of surface change of SAE 1018 steel when adding pure methyl-esters to engine oil, a SAE 15W40 mineral oil was diluted with methyl-palmitate, -oleate, -stearate, -linoleate, -laurate and -myristate, and with two typical biodiesels, soybean oil and peanut oil biodiesel, each at six different dilutions, and tested in two different instruments. Biodiesel at just 5% in oil led to enhanced wear, but some larger fractions of methyl-oleate and -laurate produced negligible surface change enhancements. Addition of methyl-linoleate and -palmitate enhanced surface degradation. Methyl ester compositions of the two tested biodiesels and their wear trends, which are found in good agreement with previous studies, are used to explain the wear differences