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1.
Biodiesel preparation from Jatropha oil catalyzed by KF/Red mud (KF/RM) was studied. The optimum values of parameters for preparation of Jatropha oil biodiesel were obtained. The conversion rate of transesterification reached 92.2% under the optimum conditions, and the used KF/RM could be regenerated. Catalyst characterization showed that KOH and KFeF4 were produced in KF/RM catalyst, which was crucial for the transesterification of Jatropha oil with methanol. Red mud was a good support to prepare KF-loaded catalyst, and prepared KF/RM was an excellent catalyst for biodiesel synthesis from Jatropha oil via transesterification reaction.  相似文献   

2.
The biodiesel (fatty acid methyl esters, FAME) was prepared by transesterification of the mixed oil (soybean oil and rapeseed oil) with sodium hydroxide (NaOH) as catalyst. The effects of mole ratio of methanol to oil, reaction temperature, catalyst amount and reaction time on the yield were studied. In order to decrease the operational temperature, a co-solvent (hexane) was added into the reactants and the conversion efficiency of the reaction was improved. The optimal reaction conditions were obtained by this experiment: methanol/oil mole ratio 5.0:1, reaction temperature 55 °C, catalyst amount 0.8 wt.% and reaction time 2.0 h. Under the optimum conditions, a 94% yield of methyl esters was reached ∼94%. The structure of the biodiesel was characterized by FT-IR spectroscopy. The sulfur content of biodiesel was determined by Inductively Coupled Plasma emission spectrometer (ICP), and the satisfied result was obtained. The properties of obtained biodiesel from mixed oil are close to commercial diesel fuel and is rated as a realistic fuel as an alternative to diesel. Production of biodiesel has positive impact on the utilization of agricultural and forestry products.  相似文献   

3.
NaOH/sepiolite nanocomposite heterogenous base catalyst (NaOH/sep.) was prepared via impregnation process and tested in a three-neck flask equipped with thermometer and reflux condenser for the production of biodiesel from transesterification of canola oil in an excess amount of methanol. The ratio of NaOH and sepiolite was selected as 1:4. The influence of various operational parameters was examined such as methanol to oil molar ratio, catalyst dosage, and reaction temperature. Untreated sepiolite and NaOH loaded sepiolite were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Scanning electron microscopy and Energy dispersive spectroscopy analysis. Overall NaOH/sep. based biodiesel production yield was examined by the help of Gas chromatography-mass spectrometry analysis. The yield was calculated from the peak areas as 80.93% which is better than that of expensive catalysis system using studies.  相似文献   

4.
A solid base catalyst was prepared by neodymium oxide loaded with potassium hydroxide and investigated for transesterification of soybean oil with methanol to biodiesel. After loading KOH of 30 wt.% on neodymium oxide followed by calcination at 600 °C, the catalyst gave the highest basicity and the best catalytic activity for this reaction. The obtained catalyst was characterized by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), N2 adsorption-desorption measurements and the Hammett indicator method. The catalyst has longer lifetime and maintained sustained activity after being used for five times, and were noncorrosive and environmentally benign. The separate effects of the molar ratio of methanol to oil, reaction temperature, mass ratio of catalyst to oil and reaction time were investigated. The experimental results showed that a 14:1 M ratio of methanol to oil, addition of 6.0% catalyst, 60 °C reaction temperature and 1.5 h reaction time gave the best results and the biodiesel yield of 92.41% was achieved. The properties of obtained biodiesel are close to commercial diesel fuel and is rated as a realistic fuel as an alternative to diesel.  相似文献   

5.
In this study, simultaneous transesterification and esterification of high acid value sunflower oil to fatty acid methyl esters was studied using Amberlyst 46 as a heterogeneous catalyst. The influence of reaction conditions such as molar ratio of methanol/oil, reaction time, and reaction temperature was investigated. The highest fatty acids methyl esters yield of 75.8% was obtained in presence of 6 wt% oleic acid content under reaction conditions of 20 wt% Amberlyst 46 catalyst amount, 6/1 methanol/oil molar ratio, reaction temperature of 130°C, and reaction time of 10 h.  相似文献   

6.
In the present work, the optimum biodiesel conversion from waste cooking oil to biodiesel through transesterification method was investigated. The base catalyzed transesterification under different reactant proportions such as the molar ratio of alcohol to oil and mass ratio of catalyst to oil was studied for optimum production of biodiesel. The optimum condition for base catalyzed transesterification of waste cooking oil was determined to be 12:1 and 5 wt% of zinc doped calcium oxide. The fuel properties of the produced biodiesel such as the calorific value, flash point and density were examined and compared to conventional diesel. The properties of produced biodiesel and their blend for different ratios (B20, B40, B60, B80 and B100) were comparable with properties of diesel oil and ASTM biodiesel standards. Tests have been conducted on CI engine which runs at a constant speed of 1500 rpm, injection pressure of 200 bar, compression ratio 15:1 and 17.5, and varying engine load. The performance parameters include brake thermal efficiency, brake specific energy consumption and emissions parameters such as Carbon monoxide (CO), Hydrocarbon (HC), Oxides of Nitrogen (NOx) and smoke opacity varying with engine load (BP). Diesel engine's thermal performance and emission parameters such as CO, HC, and NOx on different biodiesel blends demonstrate that biodiesel produced from waste cooking oil using heterogeneous catalyst was suitable to be used as diesel oil blends and had lesser emissions as compared to conventional diesel.  相似文献   

7.
The present study deals with the development of a biodiesel production reactor based on pressurized ultrasonic cavitation technique. Transesterification of Jatropha oil takes place by passing low-frequency ultrasonic irradiation in the reaction mixture flowing at pressurized conditions in the sonochemical reactor. Reaction variables such as reaction time, molar ratio, catalyst concentration, and pressure of the reaction mixture were investigated to find the optimal parameters for biodiesel production. The energy requirement decreases with increase in pressure. Very low value of Specific Energy Consumption (0.018 kWh/kg) and significantly high value of Energy Use Index (598.83) are obtained when the pressure of reaction mixture is 15 bar. Increasing the pressure thereafter, leads to nominal gains. Ultrasonic irradiation at high-pressure condition has an additional advantage of rapid reaction and lower requirement of alcohol to oil molar ratio and catalyst concentration. Fifteen bar pressure is optimal for biodiesel production.  相似文献   

8.
In the search of an alternative fuel to substitute diesel fuel, biodiesel appears as one of the most promising sources of energy for diesel engines because of its environmental advantages and also due to the evolution of the petroleum market.Refined oil is the conventional raw material for the production of this biofuel; however, its major disadvantage is the high cost of its production. Therefore, frying oils, waste oils, crude oils and/or acid oils are being tested as alternative raw materials; nevertheless, there will be some problems if a homogeneous basic catalyst (NaOH) is employed due to the high amount of free fatty acid present in the raw oil.In this work, the transesterification reaction of acid oil using solid resin, Dowex monosphere 550 A, was studied as an alternative process. Ethanol was employed to have a natural and sustainable final product. The reaction temperature's effects, the initial amount of free fatty acid, the molar ratio of alcohol/oil and the type of catalyst (homogeneous or heterogeneous) over the main reaction are analyzed and their effects compared.The results obtained show that the solid resin is an alternative catalyst to be used to produce fatty acid ethyl esters (FAEEs) by a transesterification reaction with a final conversion over 90%. On the other hand, the time required to achieve this conversion is bigger than the one required using conventional technology which employs a homogeneous basic catalyst. This reaction time needs to be optimized.  相似文献   

9.
A sulfated zirconia catalyst has been prepared by a novel one-pot vapor-controlled synthesis route using ammonium persulphate as sulfate agent. A possible formation mechanism of the catalyst is proposed. The effect of calcination temperature and S/Zr molar ratio on the structural, textural and catalytic properties of the prepared catalyst were investigated in detail using X-ray diffraction (XRD), N2 adsorption–desorption, ammonia temperature programmed desorption (NH3-TPD), Fourier transform infrared spectroscopy (FTIR) and a scanning electron microscope (SEM) which was equipped with an energy dispersive spectroscope (EDS). The results indicated that the samples calcined at 500 °C possessed zirconia of pure tetragonal structure, more content of sulfur and better distribution of acid sites on the surface of zirconia compared with the samples calcined at 600  °C at fixed S/Zr molar ratio. Moreover, they showed excellent catalytic activity with 100% yields of biodiesel for the transesterification of soybean oil with methanol.  相似文献   

10.
This paper reviews the production and characterization of biodiesel (BD or B) as well as the experimental work carried out by many researchers in this field. BD fuel is a renewable substitute fuel for petroleum diesel or petrodiesel (PD) fuel made from vegetable or animal fats. BD fuel can be used in any mixture with PD fuel as it has very similar characteristics but it has lower exhaust emissions. BD fuel has better properties than that of PD fuel such as renewable, biodegradable, non-toxic, and essentially free of sulfur and aromatics. There are more than 350 oil bearing crops identified, among which only sunflower, safflower, soybean, cottonseed, rapeseed and peanut oils are considered as potential alternative fuels for diesel engines. The major problem associated with the use of pure vegetable oils as fuels, for Diesel engines are caused by high fuel viscosity in compression ignition. Dilution, micro-emulsification, pyrolysis and transesterification are the four techniques applied to solve the problems encountered with the high fuel viscosity. Dilution of oils with solvents and microemulsions of vegetable oils lowers the viscosity, some engine performance problems still exist. The viscosity values of vegetable oils vary between 27.2 and 53.6 mm2/s whereas those of vegetable oil methyl esters between 3.59 and 4.63 mm2/s. The viscosity values of vegetable oil methyl esters highly decreases after transesterification process. Compared to no. 2 diesel fuel, all of the vegetable oil methyl esters were slightly viscous. The flash point values of vegetable oil methyl esters are highly lower than those of vegetable oils. An increase in density from 860 to 885 kg/m3 for vegetable oil methyl esters or biodiesels increases the viscosity from 3.59 to 4.63 mm2/s and the increases are highly regular. The purpose of the transesterification process is to lower the viscosity of the oil. The transesterfication of triglycerides by methanol, ethanol, propanol and butanol, has proved to be the most promising process. Methanol is the commonly used alcohol in this process, due in part to its low cost. Methyl esters of vegetable oils have several outstanding advantages among other new-renewable and clean engine fuel alternatives. The most important variables affecting the methyl ester yield during the transesterification reaction are molar ratio of alcohol to vegetable oil and reaction temperature. Biodiesel has become more attractive recently because of its environmental benefits. Biodiesel is an environmentally friendly fuel that can be used in any diesel engine without modification.  相似文献   

11.
Biodiesel production from crude rice bran oil and properties as fuel   总被引:1,自引:0,他引:1  
This research reported on the successfully production of biodiesel by transesterification of crude rice bran oil (RBO). The process included three-steps. Firstly, the acid value of RBO was reduced to below 1 mg KOH/g by two-steps pretreatment process in the presence of sulfuric acid catalyst. Secondly, the product prepared from the first process was carried out esterification with an alkaline catalyst. The influence of four variables on conversion efficiency to methyl ester, i.e., methanol/RBO molar ratio, catalyst amount, reaction temperature and reaction time, was studied at this stage. The content of methyl ester was analyzed by chromatographic analysis. Through orthogonal analysis of parameters in a four-factor and three-level test, the optimum reaction conditions for the transesterification were obtained: methanol/RBO molar ratio 6:1, usage amount of KOH 0.9% w/w, reaction temperature 60 °C and reaction time 60 min. In the third step, methyl ester prepared from the second processing step was refined to become biodiesel. Fuel properties of RBO biodiesel were studied and compared according to ASTM D6751-02 and DIN V51606 standards for biodiesel. Most fuel properties complied with the limits prescribed in the aforementioned standards. The consequent engine test showed a similar power output compared with regular diesel but consumption rate was slightly higher. Emission tests showed a marked decrease in CO, HC and PM, however, with a slight increase in NOX.  相似文献   

12.
The key objective of the present research is to optimize and investigate the biodiesel production from ricinuscommunis (castor) oil using microwave-assisted hybrid transesterfication process under various conditions such as microwave power, treatment time, ethanol:oil ratio and catalyst concentration (KOH). Response surface methodology (RSM) coupled with four factors with a three-level Box–Behnken response surface design (BBD) was employed to model the transesterfication technique. The obtained results were analyzed by analysis of variance (ANOVA) and a second-order polynomial model was developed to study the interactive effect of process factors on biodiesel production. Derringer’s desired function methodology was used for the optimization and optimum conditions for maximizing the biodiesel production. Under optimum conditions, the predicted biodiesel production was found to be 95% with a desirability value of 0.998. The fuel properties of the produced biodiesel were compared with the ASTM D6751 standards.  相似文献   

13.
In this study, potassium hydroxide-treated animal bones were employed? as a solid heterogeneous catalyst in transesterification of waste cooking oil. This catalyst was characterized by the Fourier-transform infrared spectroscopy (FTIR), and it displayed high-catalytic activity for biodiesel production. Optimum conditions for biodiesel production were catalyst loading 6.0% (w/w) of oil, methanol/oil molar ratio 9:1, calcination temperature 800°C, reaction temperature 65°C, and reaction time of 5 h, which gave maximum biodiesel yield of 84%. Reusability of the catalyst was also confirmed by repeated use of the same catalyst three times without losing much of its activity. Hence, calcined goat bones were found to be a potentially applicable catalyst for biodiesel production at industrial scale.  相似文献   

14.
In this study, the biodiesel produced from soybean crude oil was prepared by a method of alkaline-catalyzed transesterification. The important properties of biodiesel were compared with those of diesel. Diesel and biodiesel were used as fuels in the compression ignition engine, and its performance, emissions and combustion characteristics of the engine were analyzed. The results showed that biodiesel exhibited the similar combustion stages to that of diesel, however, biodiesel showed an earlier start of combustion. At lower engine loads, the peak cylinder pressure, the peak rate of pressure rise and the peak of heat release rate during premixed combustion phase were higher for biodiesel than for diesel. At higher engine loads, the peak cylinder pressure of biodiesel was almost similar to that of diesel, but the peak rate of pressure rise and the peak of heat release rate were lower for biodiesel. The power output of biodiesel was almost identical with that of diesel. The brake specific fuel consumption was higher for biodiesel due to its lower heating value. Biodiesel provided significant reduction in CO, HC, NOx and smoke under speed characteristic at full engine load. Based on this study, biodiesel can be used as a substitute for diesel in diesel engine.  相似文献   

15.
The catalyst with high activity and durability plays a crucial role in the hydrogen generation systems for the portable fuel cell generators. In the present study, a ruthenium supported on graphite catalyst (Ru/G) for hydrogen generation from sodium borohydride (NaBH4) solution is prepared by a modified impregnation method. This is done by surface pretreatment with NH2 functionalization via silanization, followed by adsorption of Ru (III) ion onto the surface, and then reduced by a reducing agent. The obtained catalyst is characterized by transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). Very uniform Ru nanoparticles with sizes of about 10 nm are chemically bonded on the graphite surface. The hydrolysis kinetics measurements show that the concentrations of NaBH4 and NaOH all exert considerable influence on the catalytic activity of Ru/G catalyst towards the hydrolysis reaction of NaBH4. A hydrogen generation rate of 32.3 L min−1 g−1 (Ru) in a 10 wt.% NaBH4 + 5 wt.% NaOH solution has been achieved, which is comparable to other noble catalysts that have been reported.  相似文献   

16.
This work determined the association between several parameters of biodiesel production from waste cooking oil (WCO) using waste bovine bone (WBB) as catalyst to achieve a high conversion to fatty acid methyl ester (%FAME). The effect of three independent variables was used as the optimum condition using response surface methodology (RSM) for maximizing the %FAME. The RSM analysis showed that the ratio of MeOH to oil (mol/mol), catalyst amount (%wt), and time of reaction have the maximum effects on the transform to FAME. Moreover, the coefficient of determination (R2) for regression equations was 99.19%. Probability value (P < 0.05) demonstrated a very good significance for the regression model. The optimal values of variables were MeOH/WCO ratio of 15.49:1 mol/mol, weight of catalyst as 6.42 wt%, and reaction time of 128.67 min. Under the optimum conditions, %FAME reached 97.59%. RSM was confirmed to sufficiently describe the range of the transesterification parameters studied and provide a statistically accurate estimate of the best transform to FAME using WBB as the catalyst.  相似文献   

17.
The diesel-like properties of biodiesel make it a good alternative for CI engines. In the present work, the scope of biodiesel as a pilot fuel has been studied and compared with diesel. The results show that the use of Jatropha oil methyl ester (JOME) and orange peel oil methyl ester (OPOME) as pilot fuel improves BTE and BSFC of dual-fuel engines compared to diesel as a pilot fuel. The use of JOME and OPOME as a pilot fuel for CNG also decreases the emissions like unburnt hydrocarbons, CO, and smoke. However, NOX emissions increase at higher load. In contrast, use of biodiesel as pilot fuel improves the performance and emissions characteristics of dual-fuel engines.  相似文献   

18.
In this study, the metallurgic sludge which contained oil and was obtained as waste of grinding, sharpening and milling parts was used in the production of hydrogen (H2) from sodium borohydride (NaBH4). The hydrolysis of NaBH4 with the metallurgic sludge catalyst was investigated depending on several parameters such as sodium hydroxide (NaOH) concentration, catalyst amount, NaBH4 concentration and temperature. The obtained metallurgic sludge catalyst was characterized by the XRD, FT-IR and SEM techniques and was evaluated for its activity in the H2 generation from NaBH4 hydrolysis. The maximum H2 production rate from the hydrolysis of NaBH4 with the metallurgic sludge catalyst was calculated as 9366 ml min−1.gcat−1. The value of activation energy was found as 48.05 kJ mol−1.  相似文献   

19.
Morpholine basic ionic liquid was synthesized with N-methyl morpholine, N-butyl bromide, and KOH by two-step method and was used to catalyze the transesterification of soybean oil with methanol to biodiesel. The structure of the catalyst were examined by 1H nuclear magnetic resonance. The effects of the molar ratio of methanol to oil, reaction temperature, and amount of catalyst on the biodiesel yield were investigated. Optimized biodiesel yield of 94.5% was achieved with catalyst amount of 3.0 wt%, and methanol to soybean oil molar ratio of 14:1 at reaction temperature of 60 °C for 6 h. The catalyst has maintained sustained activity after being employed to six cycles. The prepared biodiesel component was analyzed by gas chromatography-mass spectrometry (GC-MS) and the results showed that the biodiesel comprised of hexadecanoic acid methyl ester, 10, 13-octadecadienoic acid methyl ester, 9-octadecenoic acid methyl ester, and octadecanoic acid methyl ester, illustrating that fatty acids of soybean oil were converted completely.  相似文献   

20.
A carbon-based solid acid catalyst was prepared by the sulfonation of carbonized vegetable oil asphalt. This catalyst was employed to simultaneously catalyze esterification and transesterification to synthesis biodiesel when a waste vegetable oil with large amounts of free fatty acids (FFAs) was used as feedstock. The physical and chemical properties of this catalyst were characterized by a variety of techniques. The maximum conversion of triglyceride and FFA reached 80.5 wt.% and 94.8 wt.% after 4.5 h at 220 °C, when using a 16.8 M ratio of methanol to oil and 0.2 wt.% of catalyst to oil. The high catalytic activity and stability of this catalyst was related to its high acid site density (–OH, Brönsted acid sites), hydrophobicity that prevented the hydration of –OH species, hydrophilic functional groups (–SO3H) that gave improved accessibility of methanol to the triglyceride and FFAs, and large pores that provided more acid sites for the reactants.  相似文献   

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