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1.
In this study, a simple and solvent-free method was used to prepare sulfated zirconia-alumina (SZA) catalyst. Its catalytic activity was subsequently investigated for the transesterification of Jatropha curcas L. oil to fatty acid methyl ester (FAME). The effects of catalyst preparation parameters on the yield of FAME were investigated using Design of Experiment (DOE). Results revealed that calcination temperature has a quadratic effect while calcination duration has a linear effect on the yield of FAME. Apart from that, interaction between both variables was also found to significantly affect the yield of FAME. At optimum condition; calcination temperature and calcination duration at 490 °C and 4 h, respectively, an optimum FAME yield of 78.2 wt% was obtained. Characterization with XRD, IR and BET were then used to verify the characteristic of SZA catalyst with those prepared using well established method and also to describe the catalyst characteristic with its activity.  相似文献   

2.
The waste eggs and mollusk shells are found to be the richest sources of calcium carbonate and have been utilized for various purposes after proper treatments. When calcined at a proper temperature calcium carbonate converts into CaO, which is a metal oxide. Researchers have found that the CaO prepared from the waste shells can be used as catalyst in biodiesel production process. Utilization of waste shells as a source of CaO not only gives an opportunity to use it as catalyst but also adds value to the waste generated. In this paper a brief discussion with recent development on biodiesel production using waste shell derived solid oxide as catalyst is presented.  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.
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.  相似文献   

5.
Biofuels are renewable solutions to replace the ever dwindling energy reserves and environmentally pollutant fossil liquid fuels when they are produced from low cost sustainable feedstocks. Biodiesel is mainly produced from vegetable oils or animal fats by the method of transesterification reaction using catalysts. Homogeneous catalysts are conventionally used for biodiesel production. Unfortunately, homogeneous catalysts are associated with problems which might increase the cost of production due to separation steps and emission of waste water. Inorganic heterogeneous catalysts are potentially low cost and can solve many of the problems encountered in homogeneous catalysts. Many solid acid and base inorganic catalysts have been studied for the transesterification of various vegetables oils. The work of many researchers on the development of active, tolerant to water and free fatty acids (FFA), as well as stable inorganic catalysts for biodiesel production from vegetable oils are reviewed and discussed.  相似文献   

6.
The present work investigates the production of biodiesel from Euglena sanguinea microalgal bio-oil using calcium methoxide as a heterogeneous catalyst. The catalyst was synthesized and characterized by Fourier Transform Infra-red (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Brunauer-Emmett-Teller (BET), basicity, and basic site strength analysis. Initially, bio-oil was extracted from mass-cultivated biomass obtained from Euglena sanguinea algae. It was further pretreated and transesterified using calcium methoxide catalyst at various experimental conditions by which an optimum yield of 94.83% was achieved. The catalyst yielded above 90% up to 5 cycles of recovery and recycling. The kinetic studies were investigated at various reaction temperatures to find the rate of reaction. The activation energy and pre-exponential factor for the transesterification reaction were found to be 99.33 kJ mol?1 and 1.07 × 1014 min?1 respectively. The properties of the produced biodiesel were within the limits of ASTM D6751 standard.  相似文献   

7.
实验研究了麻疯树油在对甲苯磺酸催化剂的作用下与甲醇发生转酯化反应生成脂肪酸甲酯(生物柴油)的情况.实验结果表明,该转酯化反应的最佳操作条件为催化剂用量为麻疯树油量的5% 、油醇摩尔比为1∶ 3、反应时间为30 min、反应温度为70℃.  相似文献   

8.
Biodiesel production via transesterification of waste cooking oil (WCO) with methanol using waste chicken bone-derived catalyst was investigated. The calcium carbonate content in the waste chicken bone was converted to calcium oxide (CaO) at a calcinations temperature of 800°C. The catalysts were prepared by calcination at 300–800°C for 5 h and catalyst characterization was carried out by X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) surface area measurement. CaO was used as catalyst for biodiesel production. The results of the optimization imply that the catalyst concentration of 3.0 wt%, methanol to oil ratio of 3:1, and reaction temperature of 80°C for 3 h provide the maximum values of yield in methyl ester production. Reusability of the catalyst from calcined waste chicken bone was studied for four times, with a good yield.  相似文献   

9.
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   

10.
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   

11.
An economic and environmentally friendly catalyst derived from waste freshwater mussel shell (FMS) was prepared by a calcination-impregnation-activation method, and it was applied in transesterification of Chinese tallow oil. The as-prepared catalyst exhibits a “honeycomb” -like structure with a specific surface area of 23.2 m2 g−1. The newly formed CaO crystals are major active phase of the catalyst. The optimal calcination and activity temperature are 900 °C and 600 °C, respectively. When the reaction is carried out at 70 °C with a methanol/oil molar ratio of 12:1, a catalyst concentration of 5% and a reaction time of 1.5 h, the FMS-catalyst is active for 7 reaction cycles, with the biodiesel yield above 90%. The experimental results indicate that the FMS can be used as an economic catalyst for the biodiesel production.  相似文献   

12.
13.
Ag/bauxite nanocomposites have been prepared using in situ reduction of aqueous AgNO3 solution in a bauxite matrix and investigated for the transesterification of sunflower oil with methanol in order to study their potential as heterogeneous catalysts. The prepared nanocopmosites were characterized by XRD, SEM, EDX, FT-IR, and TG- DTA. The Central Composite Design of the Response Surface Methodology was used to optimize the effect of reaction temperature, reaction time, catalyst loading and methanol to oil molar ratio on the yield of fatty acid methyl esters. The highest yield was obtained at 67 °C reaction temperature, 3 h reaction time, 0.3 wt.% catalyst loading and 9:1 methanol to oil molar ratio. Under the optimal conditions, the methyl ester content was 94% and the catalyst successfully reused for at least 7 cycles without significant deactivation.  相似文献   

14.
This study aimed to evaluate camphor tree ash (green biomass ash) supported K2CO3 as a solid base catalyst for biodiesel production. The catalyst was prepared by way of first-calcination, K2CO3 solution impregnation, and second-calcination method. The catalytic performance of the catalyst for the preparation of biodiesel was investigated. Under the optimal conditions of K2CO3 loading of 50 wt%, first-calcination temperature of 800°C, second-calcination temperature of 500°C, catalyst concentration of 5 wt%, catalytic time of 210 min, methanol/oil molar ratio of 14:1, and catalytic temperature of 65°C, the biodiesel yield reached 92.27%.  相似文献   

15.
In the present work, zeolite based catalyst was prepared from zeolite tuft by impregnation methods. The zeolite tuft was initially treated with hydrochloric acid (16%) and then several KOH/zeolite catalysts were prepared by impregnation in KOH solutions. Various solutions of KOH with different molarities (1–6 M) were used. Further modification for the catalyst was performed by a 2nd step impregnation treatment by heating and stirring the KOH/zeolite to 80 °C for 4 h. The zeolite tuft and the prepared catalysts were characterized by several analytical techniques in order to explore their physicochemical properties. These tests include: X-Ray Fluorescence (XRF), Scanning Electron Microscopy (SEM), Zero point of Charge (PHzpc), Fourier Transform Infrared (FT-IR), Energy-dispersive X-Ray analysis (EDX) and X-Ray Diffraction (XRD). The catalysts were then used for transesterification of waste sunflower vegetable oil in order to produce biodiesel. Among the different catalysts prepared, the 1–4M KOH/TZT catalyst provided the maximum biodiesel yield of 96.7% at 50 °C reaction temperature, methanol to oil molar ratio of 11.5:1, agitation speed of 800 rpm, 335 μm catalyst particle size and 2 h reaction time. The physicochemical properties of the produced biodiesel comply with the EN and ASTM standard specifications.  相似文献   

16.
ABSTRACT

In this study, the silver-exchanged heteropolyacids were prepared by a simple and environmentally friendly ion exchange method, were found to be active in the esterification of oleic acid with methanol to produce biodiesel. The catalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM), separately. The effect of various factors was investigated to optimize the reaction conditions. The results showed that the oleic acid conversion can reach 91.3% after reacting for 3 h at 70°C, with oleic acid to methanol ratio of 1:10 and the amount of catalyst of 5 wt.%. Moreover, the catalyst could be easily separated from the reaction mixture and used repeatedly for five cycles with the oleic acid conversion over 50.1%, due to its relative stability. In particular, this catalyst can also catalyze other esterification of fatty acids with different chain length of carboxylic acid and high acid value non-edible oils, which may provide significant benefits for developing an environmentally benign and continuous process for synthesizing biodiesel in the future.  相似文献   

17.
The present work describes the synthesis of porous BaSnO3 by eco‐friendly sol‐gel method using albumin as a bio‐template agent, and its application as a solid base catalyst in biodiesel production from waste cooking oil. The physico‐chemical, textural, and morphological properties of the catalyst were evaluated by X‐ray diffraction (XRD), Brunauer‐Emmett‐Teller (BET), field emission scanning electron microscopy (FESEM), and temperature programmed desorption (TPD)–CO2 techniques. The synthesized catalyst showed considerable stability, efficient catalytic activity, and negligible metal leaching. The satisfactory performance of the catalyst could be ascribed to the presence of basic sites of different strength on the surface of the catalyst. The catalyst produced maximum biodiesel yield of 96% at optimum reaction conditions of 90°C reaction temperature, methanol to oil molar ratio of 10:1, catalyst dosage of 6 wt%, and reaction time of 2 hours. Moreover, the catalyst showed substantial reusability up to five reaction cycles without any considerable decrease in transesterification activity.  相似文献   

18.
The waste Capiz shell was utilized as raw material for catalyst production for biodiesel preparation. During calcination process, the calcium carbonate content in the waste capiz shell was converted to CaO. This calcium oxide was used as catalyst for transesterification reaction between palm oil and methanol to produce biodiesel. The biodiesel preparation was conducted under the following conditions: the mole ration between methanol and palm oil was 8:1, stirring speed was 700 rpm, and reaction temperature was 60 °C for 4, 5, and 6 h reaction time. The amount of catalyst was varied at 1, 2, 3, 4, and 5 wt %. The maximum yield of biodiesel was 93 ± 2.2%, obtained at 6 h of reaction time and 3 wt % of amount of catalyst. In order to examine the reusability of catalyst developed from waste of capiz (Amusium cristatum) shell, three transesterification reaction cycles were also performed.  相似文献   

19.
A preliminary investigation on the suitability of various non-edible oil seeds for the integral utilisation of their fractions for production of biodiesel and other products was carried out. The oil seeds considered were jatropha (Jatropha curcas), neem (Azadirachta indica), moringa (Moringa oleifera), trisperma (Aleurites trisperma), castor beans (Ricinus communis) and candlenut (Aleurites moluccana). The highest oil content (62.0% (w/w)) was found in trisperma seeds, but the use of that oil for biodiesel production is restricted by its high content of polyunsaturated fatty acids. The oils of castor beans and moringa contained 86.0% of ricinoleic acid and 70.6% of oleic acid, respectively, while in the oils from the other seeds no predominance of any acid was observed. According to the oil yield and to the fatty acid composition of the oil, jatropha was identified as the most promising oil seed for biodiesel production in Cuba. All the press cakes were rich in protein, the highest content (68.6%) being detected in moringa cake. The investigation revealed that the husks of neem and moringa can be considered potential substrates for ethanol production due to their high cellulose content (approximately 30%). A high concentration (4.3%) of acetyl groups was found in neem husks, what is favourable for the hydrolytic conversion of polysaccharides to simple sugars. A high protein content (15.2%) was detected in moringa husks, which is a positive feature for lowering the cost of nutrient supplementation in ethanolic fermentation.  相似文献   

20.
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   

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