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1.
采用分步浸渍法制备了催化剂NiMoW/γ-Al_2O_3。以地沟油为原料,通过固定床反应器对NiMoW/γ-Al_2O_3催化剂的性能进行了评价。地沟油经加氢脱氧等反应得到C_(15)~C_(18)的直链柴油烷烃,即第二代生物柴油。考察了不同反应温度、反应压力、液态空速下产物的质量收率、脱氧率和选择性。实验结果表明,适宜的反应条件为:反应温度380℃反应压力5.0MPa液态空速1.0h~(-1),在该反应条件下,生物柴油的质量收率为84.63%,脱氧率不低于99.98%.  相似文献   

2.
首次采用回流法制备了二氧化钛负载磷钨钼杂多酸催化剂H3PW6Mo6O40/TiO2,该催化剂的适宜制备条件为:原料质量比m(TiO2)∶m(H3PW6Mo6O40)=1∶2.0,水用量30mL,回流反应时间2.0h,活化温度150℃。以H3PW6Mo6O40/TiO2为催化剂,对以环己酮与乙二醇为原料合成环己酮乙二醇缩酮的反应条件进行了研究,较系统地研究了酮醇物质的量比、催化剂用量、反应时间对收率的影响。实验结果表明,在n(环己酮)∶n(乙二醇)=1.0∶1.5、催化剂用量占反应物料总质量的0.8%、反应时间1.0h的条件下,环己酮乙二醇缩酮的收率为86.3%。  相似文献   

3.
废弃油脂超临界法制备生物柴油研究   总被引:2,自引:0,他引:2  
以废弃油脂为原料,利用超临界法制备生物柴油.通过单因素实验及正交实验研究了醇油摩尔比、反应压力、催化剂用量、反应时间、反应温度等因素对生物柴油产率的影响.结果表明,在实验范围内各影响因素对生物柴油产率作用的大小依次为:反应温度>反应压力>催化剂用量>反应时间>醇油摩尔比.废弃油脂超临界法制备生物柴油的最佳工艺条件为:反应温度240℃,反应压力10MPa,反应时间6min,催化剂用量0.06%,醇油摩尔比40/1.在此条件下,生物柴油产率达到99.37%.  相似文献   

4.
正交法探讨制备生物柴油的优化条件   总被引:7,自引:0,他引:7  
植物油在NaOH为催化剂的作用下通过甲醇酯交换反应生成脂肪酸甲酯(生物柴油)。考察了反应条件如醇油比、催化剂用量、反应温度、反应时间等的变化对生物柴油得率的影响。应用正交实验的方法找出植物油酯交换反应的最佳反应条件为:反应温度40℃,醇油物质的量比6∶1,催化剂用量0.8%,反应时间60 min。在此反应条件下生物柴油得率可达99.2%。实验所得的生物柴油主要质量指标已达到德国DINV51.606生物柴油质量标准。  相似文献   

5.
实验考察了温度、压力、H2/CO和空速等不同操作条件对固定床熔铁催化剂费托合成液态产物的影响,得出了液态产物在不同操作条件下的时空产率、烃类产率、含碳量(C5~C13)、烯烷比及正构烷烃与支链烷烃(正支比)的一些变化规律。  相似文献   

6.
棉籽油制备生物柴油的研究   总被引:4,自引:0,他引:4  
采用棉籽油为原料,在催化剂(KOH)的作用下,通过甲醇酯交换反应制备生物柴油;考察了醇油比、催化剂用量、反应温度、反应时间对生物柴油收率的影响;确定了棉籽油酯交换反应的适宜反应条件:醇油物质的量比6:1,催化剂用量1.2%,反应温度60℃,反应时间30 min,在此条件下,柴油收率为96.3%,其质量指标密度、牯度、甲酯和硫含量等符合国外标准.  相似文献   

7.
乌桕籽的含油率高达40%,是生产生物柴油的优质原料。本研究采用绿色环保节能高效的乌桕籽油提取方法,以高压蒸汽作为水剂提取油脂的方法,进行了相关工艺的实验研究,以乌桕油脂皂化物为研究对象,通过微波极化皂化物羧基端促进脱羧制备优质烃类燃料。探讨了料液比、烘烤时间、烘烤温度、pH值、高压蒸汽处理时间等因素对油脂提取率的影响。微波裂解所得到液态产物为皂类干重的60%以上,裂解液态产物的密度为0.865 g/cm3,黏度2.73 mm2/s,与柴油的性质基本相似。研究结果为利用乌桕籽油生产生物柴油的工业化提供了一定基础。  相似文献   

8.
通过溶胶-凝胶-包埋法制备的二氧化硅负载甲烷磺酸固体酸催化剂,用于大豆油与乙醇的酯交换制备生物柴油,考察了催化剂的处理温度、乙醇与大豆油物质的量比、催化剂用量、正庚烷用量和反应时间的影响。结果表明,二氧化硅负载的甲烷磺酸具有较高的酯交换反应活性。制备生物柴油的最佳条件为:催化剂焙烧温度130 ℃、醇油物质的量比6∶1、催化剂用量为大豆油质量的5.0%,溶剂正庚烷用量为大豆油质量的30.0%,反应时间6 h。在此条件下,产品收率可达98.33%。与固体碱催化剂相比,固体酸催化剂对原料的酸度有更强的适应性。  相似文献   

9.
以猪油为原料,优化了活性炭负载碳酸钠催化猪油制备生物柴油的工艺。分别采用单因素实验和正交实验对反应条件进行了优化,考察了醇油摩尔比、催化剂用量、反应时间、反应温度的影响,结果表明最佳反应条件为:醇油摩尔比9∶1、催化剂用量为9%、反应时间3.5 h、反应温度70℃。在此条件下,生物柴油产率为95.3%。  相似文献   

10.
以水杨酸和乙酸酐为原料,以二氧化硅负载硅钨钼酸H4SiW6Mo6O40/SiO2为催化剂。探讨H4SiW6Mo6O40/SiO2对合成反应的催化活性,系统地研究了水杨酸和乙酸酐的物质的量比、催化剂用量、反应时间等因素对产物收率的影响。实验表明:H4SiW6Mo6O40/SiO2是合成乙酰水杨酸的良好催化剂,固定水杨酸用量为0.015 mol,在n(水杨酸)∶n(乙酸酐)=1∶2.0,催化剂用量为0.3g,反应时间15min的最佳条件下,乙酰水杨酸的收率可达75.1%。  相似文献   

11.
In recent years, the acceptance of fatty acid methyl esters (biodiesel) as an alternative fuel has rapidly grown in EU. The most common method for biodiesel production is based on triglyceride transesterification to methyl esters with dissolved sodium hydroxide in methanol as catalyst. In this study, cottonseed oil and used frying oil were subjected to the transesterification reaction with tetramethyl ammonium hydroxide and benzyltrimethyl ammonium hydroxide as strong base catalysts. This work investigates the optimum conditions for biodiesel production using amine-based liquid catalysts. Biodiesel ester content was strongly related with the type of feedstock and the reaction variables, such as those of the catalyst concentration, methanol to oil molar ratio, and reaction time. The overall results suggested that the transesterification of cottonseed oil achieved high conversion rates with both catalysts, while the use of waste oil resulted in lower yields of methyl esters due to the possible formation of amides.  相似文献   

12.
固体碱催化黄连木籽油制备生物柴油   总被引:2,自引:1,他引:1  
制备了K2CO3/Mg(A l)O固体碱催化剂,适宜制备条件为:K2CO3负载量30%、在700℃下焙烧4 h。用比表面积测定仪、X射线衍射仪、红外光谱仪对其进行了表征。以黄连木籽油为原料,开展了酯交换法制备生物柴油的研究,考察了主要影响因素:醇油摩尔比、催化剂用量、反应时间和反应温度对酯交换反应的影响,得到的酯交换反应适宜条件为:以黄连木籽油0.01 mol计,醇油摩尔比12∶1、催化剂用量为黄连木籽油质量的4.0%、反应时间2.5 h、反应温度68℃。在该条件下生物柴油的收率可达99%以上。催化剂经4次循环使用,生物柴油收率仍可保持在96%以上。用FTIR1、HNMR对所制备的产品进行了表征,证明产品中含有饱和脂肪酸甲酯和不饱和脂肪酸甲酯。  相似文献   

13.
高酸价油脂制备生物柴油的研究   总被引:2,自引:1,他引:1  
以高游离脂肪酸含量的大豆酸化油为原料,在较高的压力和温度条件下,经催化甲酯化制备生物柴油,研究了甲酯化的优化反应条件并在此条件下对大豆酸化油、菜籽酸化油、地沟油的甲酯化效率进行了验证试验。结果表明在醇油质量比1:1.25,催化剂NaA/MgR用量为油质量的 1%,压力 3.0 MPa,温度 188℃,反应时间 120 min,3种原料油脂总脂肪酸甲酯含量达到 95%,生物柴油得率在 94% 左右。所得生物柴油产品质量指标符合ASTM 6751-03a的质量指标,且本工艺可以实现工业化。  相似文献   

14.
Biodiesel is an alternative fuel for diesel engines that consists of the monoalkyl esters of vegetable oils or animal fats. Currently, most biodiesel consists of methyl esters, which have poor cold-flow properties. Methyl esters of soybean oil will crystallize and plug fuel filters and lines at about 0°C. However, isopropyl esters have better cold-flow properties than methyl esters. This paper describes the production of isopropyl esters and their evaluation in a diesel engine. The effects of the alcohol amount, the catalyst amount, and two different catalysts on producing quality biodiesel were studied. Both sodium isopropoxide and potassium isopropoxide were found to be suitable for use in the transesterification process. A 20∶1 alcohol/TG molar ratio and a catalyst amount equal to 1% by weight (based on the TG amount) of sodium metal was the most cost-effective way to produce biodiesel fuel. The emissions from a diesel engine running on isopropyl esters made from soybean oil and yellow grease were investigated by comparing them with No. 2 diesel fuel and methyl esters. For nitrogen oxide emission, the difference between the biodiesel produced from soybean oil and yellow grease was greater than the difference between the methyl and isopropyl esters of both feedstocks. The other emissions from using isopropyl esters were about 50% lower in hydrocarbons, 10–20% lower in carbon monoxide, and 40% lower in smoke number when compared with No. 2 diesel fuel.  相似文献   

15.
朱超  姚志龙 《工业催化》2011,19(4):57-60
分别以γ-Al2O3和NiAl2O4为载体制备了用于脂肪酸甲酯加氢制备液体石蜡的催化剂,考察了载体酸性和工艺条件对脂肪酸甲酯加氢制备液体石蜡的影响。结果表明,载体酸性影响催化剂生成液体石蜡的选择性,适宜工艺条件为:反应温度400 ℃,反应氢压5.0 MPa,空速1.0 h-1,氢油物质的量比15.56∶1。以Ni/NiAl2O4为催化剂,脂肪酸甲酯转化率达98.9%,正构烷烃选择性达100%。  相似文献   

16.
The deoxygenation of methyl octanoate and methyl stearate over alumina-supported Pt was studied in both the vapor phase in a flow reactor and in the liquid phase in a semibatch reactor. The conversion of both methyl esters resulted in hydrocarbons with one carbon less than the fatty acid of the corresponding ester as the dominant products. In the vapor phase, acid and other oxygenates were observed in low concentrations, but they were not detected when the reaction was conducted in the liquid phase. Under He, condensation products (from esterification and ketonization) were observed. By contrast, under H2, mostly paraffins were obtained. These results show promise to directly produce standard diesel components from biodiesel.  相似文献   

17.
Y.C. Sharma  Bhaskar Singh 《Fuel》2010,89(7):1470-1474
Kusum (Schleichera triguga), a non-edible oil bearing plant has been used as an ideal feedstock for biodiesel development in the present study. Various physical and chemical parameters of the raw oil and the fatty acid methyl esters derived have been tested to confirm its suitability as a biodiesel fuel. The fatty acid component of the oil was tested by gas chromatography. The acid value of the oil was determined by titration and was found to 21.30 mg KOH/g which required two step transesterification. Acid value was brought down by esterification using sulfuric acid (H2SO4) as a catalyst. Thereafter, alkaline transesterification was carried out using potassium hydroxide (KOH) as catalyst for conversion of kusum oil to its methyl esters. Various parameters such as molar ratio, amount of catalyst and reaction time were optimized and a high yield (95%) of biodiesel was achieved. The high conversion of the feedstock into esters was confirmed by analysis of the product on gas chromatograph-mass spectrometer (GC-MS). Viscosity and acid value of the product biodiesel were determined and found to be within the limits of ASTM D 6751 specifications. Elemental analysis of biodiesel showed presence of carbon, hydrogen, oxygen and absence of nitrogen and sulfur after purification. Molar ratio of methanol to oil was optimized and found to be 10:1 for acid esterification, and 8:1 for alkaline transesterification. The amounts of H2SO4 and KOH, 1% (v/v) and 0.7% (w/w), respectively, were found to be optimum for the reactions. The time duration of 1 h for acid esterification followed by another 1 h for alkaline transesterification at 50 ± 0.5 °C was optimum for synthesis of biodiesel.  相似文献   

18.
李瑞丽  阳思远  刘瑛 《化工进展》2012,31(4):813-819,843
以小桐梓油生物柴油为原料,在固定床连续反应器中,以Hβ型分子筛为催化剂,采用异构化反应改善生物柴油的低温流动性。考察了反应温度、质量空速、助剂(水)加入量等不同条件对生物柴油低温流动性的影响。实验结果表明,催化剂选用硅铝比为25的Hβ分子筛的情况下,反应温度为250℃、质量空速为1.0 h-1、助剂加入量为1.2%为最佳反应条件,小桐梓油生物柴油在最佳反应条件下进行异构化反应,凝点从1℃降低到-5℃,降幅为6℃。对生物柴油和异构化产物进行了色谱、质谱、核磁共振等表征,结果发现,低温流动性改善的原因是生物柴油的主要成分油酸甲酯、亚油酸甲酯发生了异构化反应,产生了带支链的异构体。  相似文献   

19.
疏水改性氧化钙催化制备生物柴油的研究   总被引:1,自引:0,他引:1  
以溴化苄作为改性剂,采用化学键合方法对市售氧化钙进行表面改性,考察改性氧化钙固体碱催化菜籽油-甲醇酯交换反应制备生物柴油的性能,并在此基础上对该催化体系的耐水性进行考察。通过对反应体系中醇/油摩尔比、催化剂用量和反应时间进行优化,最终得出在醇/油摩尔比为15∶1,催化剂用量为5%以及表面改性剂溴化苄用量为0.2%时,表面改性氧化钙上生物柴油产率在反应3h即可达到99.8%,而未改性氧化钙为催化剂时在相同反应条件下生物柴油产率仅为35.3%。  相似文献   

20.
GC-MS 法分析生物柴油中脂肪酸甲酯成分的研究   总被引:2,自引:2,他引:0  
通过利用不同气相色谱-质谱条件对生物柴油中的脂肪酸甲酯成分的分析研究,优选一个 GC-MS 条件,选用PEG-20M的色谱柱,柱温用 150℃ 恒温,进样量为 0.2 μL,分析时间仅用了 12 min,能很好地分离和鉴定生物柴油中主要的10个脂肪酸甲酯,该方法可用于不同植物油制备的生物柴油样品中的脂肪酸甲酯成分的 GC-MS 分析。  相似文献   

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