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Reduction of high content of free fatty acid in sludge palm oil via acid catalyst for biodiesel production 总被引:1,自引:0,他引:1
Adeeb HayyanMd. Zahangir Alam Mohamed E.S. MirghaniNassereldeen A. Kabbashi Noor Irma Nazashida Mohd HakimiYosri Mohd Siran Shawaluddin Tahiruddin 《Fuel Processing Technology》2011,92(5):920-924
In this study, sulphuric acid (H2SO4) was used in the pretreatment of sludge palm oil for biodiesel production by an esterification process, followed by the basic catalyzed transesterification process. The purpose of the pretreatment process was to reduce the free fatty acids (FFA) content from high content FFA (> 23%) of sludge palm oil (SPO) to a minimum level for biodiesel production (> 2%). An acid catalyzed esterification process was carried out to evaluate the low content of FFA in the treated SPO with the effects of other parameters such as molar ratio of methanol to SPO (6:1-14:1), temperature (40-80 °C), reaction time (30-120 min) and stirrer speed (200-800 rpm). The results showed that the FFA of SPO was reduced from 23.2% to less than 2% FFA using 0.75% wt/wt of sulphuric acid with the molar ratio of methanol to oil of 8:1 for 60 min reaction time at 60 °C. The results on the transesterification with esterified SPO showed that the yield (ester) of biodiesel was 83.72% with the process conditions of molar ratio of methanol to SPO 10:1, reaction temperature 60 °C, reaction time 60 min, stirrer speed 400 rpm and KOH 1% (wt/wt). The biodiesel produced from the SPO was favorable as compared to the EN 14214 and ASTM D 6751 standard. 相似文献
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用氢氧化钾作催化剂,考察了反应温度、催化剂用量、醇油摩尔比、反应时间对棕榈油和甲醇制备生物柴油产率的影响。结果表明,最佳反应条件为:反应温度40℃,催化剂用量0.6%,醇油摩尔比6∶1,反应时间2.0 h。此时,生物柴油产率可达97.82%。 相似文献
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Biodiesel is gaining more and more importance as an attractive fuel due to the depleting fossil fuel resources. Chemically biodiesel is monoalkyl esters of long chain fatty acids derived from renewable feed stock like vegetable oils and animal fats. It is produced by transesterification in which, oil or fat is reacted with a monohydric alcohol in presence of a catalyst to give the corresponding monoalkyl esters. This article reports experimental data on the production of fatty acid methyl esters from vegetable oils, soybean and cottonseed oils using sodium hydroxide as alkaline catalyst. The variables affecting the yield and characteristics of the biodiesel produced from these vegetable oils were studied. The variables investigated were reaction time (1-3 h), catalyst concentration (0.5-1.5 w/wt%), and oil-to-methanol molar ratio (1:3-1:9). From the obtained results, the best yield percentage was obtained using a methanol/oil molar ratio of 6:1, sodium hydroxide as catalyst (1%) and 60 ± 1 °C temperature for 1 h. The yield of the fatty acid methyl ester (FAME) was determined according to HPLC. The composition of the FAME was determined according to gas chromatography. The biodiesel samples were physicochemically characterized. From the results it was clear that the produced biodiesel fuel was within the recommended standards of biodiesel fuel. 相似文献
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棕榈油酯交换制备生物柴油的反应动力学 总被引:1,自引:1,他引:0
在甲醇与棕榈油的摩尔比为6∶1和催化剂KOH用量为棕榈油质量1.0%的条件下,研究不同温度下棕榈油制备生物柴油的酯交换反应动力学,采用Origin软件拟合曲线方程,建立棕榈油酯交换反应的宏观动力学模型。研究结果表明:棕榈油制备生物柴油的酯交换反应遵循1.40级动力学方程,反应速率随温度的升高而加快,二者符合Arrhenius方程,该反应的活化能为27.23 kJ/mol,频率因子为1.4×103。文中研究建立的反应动力学模型将对扩大试验研究提供理论依据和基础数据支持。 相似文献
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The immiscibility of methanol and vegetable oil leads to a mass-transfer resistance in the transesterification of vegetable oil. To overcome this problem, dimethyl ether (DME) was used as an environmentally friendly cosolvent to produce a homogeneous solution. Methylesterifications of corn oil in both the presence and the absence of DME were performed using p-toluenesulfonic acid (PTSA), benzenesulfonic acid and sulfuric acid. PTSA showed highest catalytic activity. The yield of FAME reached 97.1% when 4 wt% of PTSA based on the oil weight was used at 80 °C with a reaction time of 2 h in the presence of DME. The obtained biodiesel was composed of methyl palmitate (9.1 wt%), methyl oleate (33.9 wt%), methyl linoleate (53.5 wt%), methyl linolenate (3.0 wt%) and methyl arachidate (0.5 wt%), and it was similar to the biodiesel compositions from corn oil as reported. The effects of concentrations of FFA and water on FAME yields were also investigated. All results suggested that the reaction rate was greatly improved by the addition of DME to the reaction system. 相似文献
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Two ternary systems of fats were studied. In the first system, low-erucic acid rapeseed oil (LERO), hydrogenated lowerucic
acid rapeseed oil (HLERO), and palm oil (PO) were blended. In the second system, hydrogenated palm oil (HPO) was used instead
of PO and was blended with LERO and HLERO. The blends were then studied for their physical properties such as solid fat content
(SFC), melting curves by DSC, and polymorphism (X-ray). HPO showed the highest melting enthalpy after 48 h at 15°C (141±1
J/g), followed by HLERO (131±2 J/g), PO (110±2 J/g), and LERO (65±4 J/g). Binary phase behavior diagrams were constructed
from the DSC and X-ray results. Iso-line diagrams of partial-melting enthalpies were constructed from the DSC results, and
binary and ternary isosolid diagrams were constructed from the NMR results. The isosolid diagrams demonstrated formation of
a eutectic along the binary blend of PO/HLERO. However, no eutectic effect was observed along the binary lines of HPO/HLERO,
PO/LERO, HPO/LERO, or HLERO/LERO. The same results were found with the iso-line diagrams of partial-melting enthalpies. As
expected, addition of PO or HPO increased polymorphic stability in the β′ form of the HLERO/LERO mixture. 相似文献
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The kinetics of palm oil and mustard oil transesterification are compared. Transesterification of palm oil and mustard oil using KOH as a catalyst was performed at various reaction temperatures ranging from 40 to 60°C. The reaction steps are reversible and transesterification is favoured at elevated temperatures. The reaction step of triglyceride to diglyceride is the rate determining step (RDS) that controls kinetics of overall transesterification with activation energies of 30.2 and 26.8 kJ/mol for palm oil and mustard oil transesterification, respectively. It is found that percentage of saturated compounds play a vital role on transesterification kinetics. © 2011 Canadian Society for Chemical Engineering 相似文献
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Biodiesel fuel is gaining more and more importance because of the depletion and uncontrollable prices of fossil fuel resources. The use of vegetable oil and their derivatives as alternatives for diesel fuel is the best answer and as old as Diesel Engine. Chemically biodiesel fuel is the mono alkyl esters of fatty acids derived from renewable feed stocks like vegetable oils and animal fats. Safflower oil contains 75-80% of linoleic acid; the presence of this unsaturated fatty acid is useful in alleviating low temperature properties like pour point, cloud point and cold filter plugging point. In this paper we studied the effect of various parameters such as temperature, molar ratio (oil to alcohol), and concentration of catalyst on synthesis of biodiesel fuel from safflower oil. The better suitable conditions of 1:6 molar ratio (oil to alcohol), 60 degrees C temperature and catalyst concentration of 2% (by wt. of oil) were determined. The finally obtained biodiesel fuel was analyzed for fatty acid composition by GLC and some other properties such as flash point, specific gravity and acid value were also determined. From the results it was clear that the produced biodiesel fuel was with in the recommended standards of biodiesel fuel with 96.8% yield. 相似文献
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Felycia Edi Soetaredjo Aning Ayucitra Suryadi Ismadji Anastasia Lidya Maukar 《Applied Clay Science》2011,53(2):341-346
A potential application of KOH/bentonite as a catalyst for biodiesel production was studied. A series of KOH/bentonite catalysts was prepared by impregnation of bentonite from Pacitan with potassium hydroxide. The ratios between KOH and bentonite were 1:20, 1:10, 1:5, 1:4, 1:3, and 1:2. The characterization of KOH/bentonite and natural bentonite was conducted by nitrogen adsorption and XRD analysis. The effects of various reaction variables on the yield of biodiesel were investigated. The highest yield of biodiesel over KOH/bentonite catalyst was 90.70 ± 2.47%. It was obtained at KOH/bentonite 1:4, reaction time of 3 h, 3% catalyst, methanol to oil ratio of 6, and the reaction temperature at 60 °C. 相似文献
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Continuous production of biodiesel fuel from vegetable oil using supercritical methanol process 总被引:1,自引:0,他引:1
Huayang He 《Fuel》2007,86(3):442-447
A system for continuous transesterification of vegetable oil using supercritical methanol was developed using a tube reactor. Increasing the proportion of methanol, reaction pressure and reaction temperature can enhance the production yield effectively. However, side reactions of unsaturated fatty acid methyl esters (FAME) occur when the reaction temperature is over 300 °C, which lead to much loss of material. There is also a critical value of residence time at high reaction temperature, and the production yield will decrease if the residence time surpasses this value. The optimal reaction condition under constant reaction temperature process is: 40:1 of the molar ratio of alcohol to oil, 25 min of residence time, 35 MPa and 310 °C. However, the maximum production yield can only be 77% in the optimal reaction condition of constant reaction temperature process because of the loss caused by the side reactions of unsaturated FAME at high reaction temperature. To solve this problem, we proposed a new technology: gradual heating that can effectively reduce the loss caused by the side reactions of unsaturated FAME at high reaction temperature. With the new reaction technology, the methyl esters yield can be more than 96%. 相似文献
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Ainie Kuntom Wai-Lin Siew Yew-Ai Tan 《Journal of the American Oil Chemists' Society》1994,71(5):525-528
Palm acid oil (PAO) is a by-product obtained from the alka-line refining of palm oil. It is used for making laundry soaps
and for producing calcium soaps for animal feed formulations. The properties and composition of PAO may differ according to
variations in the palm oil feedstock and the alkaline refining process. Because information on the characteristics of PAO
is limited, this investigation aims to establish the properties of this product. Quality and oxidative parameters of 27 samples
of PAO were determined. The six parameters analyzed were moisture and free fatty acid content, peroxide value, iodine value,
saponification value and unsaponifiable matter. Headspace-gas-chromatographic (HSGC) analysis and gas-chromatographic analysis
of the extract from Likens-Nickerson steam distillation of the samples were also carried out. Mean moisture content was 0.98%,
free fatty acids 62.6% (palmitic acid), peroxide value 4.1 meq/kg, iodine value 50.2, saponification value 186 and unsaponifiable
matter 0.53 HSGC profiles of a few samples showed the presence of one to three peaks, while the steam distillation extract
showed the presence of aldehydes, ketones, furans and acids. 相似文献
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Yomi Watanabe Yuji Shimada Akio Sugihara Hideo Noda Hideki Fukuda Yoshio Tominaga 《Journal of the American Oil Chemists' Society》2000,77(4):355-360
Candida antarctica lipase is inactivated in a mixture of vegetable oil and more than 1∶2 molar equivalent of methanol against the total fatty
acids. We have revealed that the inactivation was eliminated by three successive additions of 1∶3 molar equivalent of methanol
and have developed a three-step methanolysis by which over 95% of the oil triacylglycerols (TAG) were converted to their corresponding
methyl esters (ME). In this study, the lipase was not inactivated even though 2∶3 molar equivalent of methanol was present
in a mixture of acylglycerols (AG) and 33% ME (AG/ME33). This finding led to a two-step methanolysis of the oil TAG: The first-step
was conducted at 30°C for 12 h with shaking in a mixture of the oil, 1∶3 molar equivalent of methanol, and 4% immobilized
lipase; the second-step reaction was done for 24 h after adding 2∶3 molar equivalent of methanol (36 h in total). The two-step
methanolysis achieved more than 95% of conversion. When two-step reaction was repeated by transferring the immobilized lipase
to a fresh substrate mixture, the enzyme could be used 70 cycles (105 d) without any decrease in the conversion. From the
viewpoint of the industrial production of biodiesel fuel production, the two-step reaction was conducted using a reactor with
impeller. However, the enzyme carrier was easily destroyed, and the lipase could be used only several times. Thus, we attempted
flow reaction using a column packed with immobilized Candida lipase. Because the lipase packed in the column was drastically inactivated by feeding a mixture of AG/ME33 and 2∶3 molar
equivalent of methanol, three-step flow reaction was performed using three columns packed with 3.0 g immobilized lipase. A
mixture of vegetable oil and 1∶3 molar equivalent of methanol was fed into the first column at a constant flow rate of 6.0
mL/h. The eluate and 1∶3 molar equivalent of methanol were mixed and then fed into the second column at the same flow rate.
The final step reaction was done by feeding a mixture of eluate from the second column and 1∶3 molar equivalent of methanol
at the same flow rate. The ME content in the final-step eluate reached 93%, and the lipase could be used for 100 d without
any decrease in the conversion. 相似文献
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《Fuel》2005,84(12-13):1717-1720
Methyl esters of vegetable oils have been successfully evaluated as diesel substitute. In the present study, other alkyl esters, namely ethyl and isopropyl esters of crude palm oil and crude palm stearin were synthesized via chemical transesterification reactions and subsequently evaluated for their fuel properties. Generally, these alkyl esters exhibit higher viscosity (4.4×10−6m2/s–5.2×10−6 m2/s) compared to that of petroleum diesel (4.0×10−6 m2/s). However, compared to petroleum diesel, these alkyl esters exhibit acceptable gross heat of combustion (39–41 MJ/kg). Originated from renewable origin, the low sulfur content in alkyl esters emits much lower SO2. These alkyl esters are much safer than petroleum diesel in terms of safety for storage and transportation as they possess high flash points. They may find applications in the fuel industry besides utilization as oleochemicals. 相似文献