共查询到16条相似文献,搜索用时 203 毫秒
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综述了超临界流体法制备生物柴油技术,主要介绍了超临界流体法制备生物柴油的流程、工艺条件、反应动力学、原料中的水和游离脂肪酸对酯交换反应的影响,并概述了超临界流体法的优势、问题及发展前景. 相似文献
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酯交换制备生物柴油的机理及应用研究 总被引:1,自引:1,他引:0
综述了酯交换法(包括化学催化法、酶催化法和超临界法)制备生物柴油的机理和最新研究进展,并讨论各种制备方法的优缺点,指出生物柴油的未来发展前景。 相似文献
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生物柴油主要成分是动、植物油脂与醇经酯交换反应得到的脂肪酸单烷基酯。与普通柴油相比,生物柴油具有高十六烷值、低芳烃含量、高闪点、较好的低温启动性等优点。综述了酸碱催化法、酶催化法、超临界法、催化加氢法和微生物油脂法等生物柴油催化合成技术的最新研究进展,主要从生物柴油收率、反应条件、制备成本和环境影响等角度分析比较。展望了生物柴油在我国的发展前景。 相似文献
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酸值不合格是以非食用油脂为原料制备生物柴油技术经常存在的问题,所以降低酸值是控制生物柴油产品质量的研究热点。降酸工艺主要围绕生物柴油高酸值原料反应控制酸值和酸值不合格生物柴油产品经过技术处理获得合格产品。总结了应用酸碱催化法、超临界法、酶催化法和吸附降酸相关技术降低生物柴油酸值的研究成果,分析了它们各自的优点和存在问题,并展望了生物柴油降酸方法的发展。 相似文献
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脂肪酶法制备生物柴油的研究现状及展望 总被引:1,自引:0,他引:1
脂肪酶法制备生物柴油具有反应条件温和、醇用量小、甘油易回收和无废物产生等特点。对用于制备生物柴油的脂肪酶类型(动物脂肪酶、植物脂肪酶及微生物脂肪酶)、用于脂肪酶法制备生物柴油的原料油脂类型(植物油脂、动物油脂、微藻油脂及废弃油脂)以及脂肪酶法制备生物柴油的方式(游离脂肪酶催化法、固定化脂肪酶催化法、复合脂肪酶协同催化法)进行了综述;并提出了脂肪酶法制备生物柴油的研究与发展方向,如对酶制剂的研究、生物柴油原料的解决以及对脂肪酶的使用方式进行改进,为今后脂肪酶法制备生物柴油的研究提供思路。 相似文献
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以蔗糖为碳源、SiO_2为模板剂,采用碳化-磺化法制备介孔碳基固体酸催化剂,通过酸碱滴定、BET、XRD、FT-IR、SEM等方法对其进行表征,考察碳化温度、磺化温度对催化剂性能的影响,并将其用于大豆油与甲醇的酯交换反应,考察反应条件及原料中脂肪酸含量的影响。结果表明:制备催化剂的适宜条件为碳化温度400℃、磺化温度170℃;大豆油与甲醇酯交换反应的最佳条件为反应温度130℃、醇油摩尔比30、反应时间4h、催化剂用量(占大豆油质量的百分比)8%,生物柴油收率最高达95.94%;连续使用5次后,生物柴油收率仍达到85.46%,说明催化剂具有良好的稳定性;原料中的脂肪酸对催化剂性能有一定的负面影响,但当脂肪酸质量分数达到15%时,生物柴油收率依然可达90%以上。 相似文献
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Huang Fenghong Guo Pingmei Huang Qingde 《中国炼油与石油化工》2005,(3):33-38
Till now, most part of the biodiesel is produced from the refined vegetable oils using methanol as feedstock in the presence of an alkali catalyst. However, large amount of waste edible oils and grease are available. The difficulty with alkali-catalyzed esterification of these oils is that they often contain large amount of free fatty acids (FFA), polymers and decomposition products. These free fatty acids can quickly react with the alkali catalyst to produce soaps that inhibit the separation of the ester and glycerine. An esterification and transesterification process is developed to convert the high FFA oil to its monoesters, The first step, the acidcatalyzed esterification with glycerine and these FFA reduces the FFA content of the oil and grease to less than 3%, and then an azeotropic distillation solvent is used to remove the water. The major factors affecting the conversion efficiency of the process such as glycerol to free fatty acid molar ratio, catalyst amount, reaction temperature and reaction duration are analyzed, The second step, alkali-catalyzed transesterificatiou process converts the products of the first step to its monoesters and glycerol, and then the glycerol is recycled for utilization in the first step. Technical indicators of the biodiesel product can meet the ASTM 6751 standard. 相似文献
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废弃食用油脂的危害与资源化利用 总被引:8,自引:0,他引:8
废弃食用油脂是失去食用价值的油脂废弃物,包括餐饮业废油(俗称地沟油、潲水油、泔水油)、含油皂脚和含油废水。废弃食用油脂中含有大量脂肪酸等含碳有机物,具有污染环境和回收利用的双重性。合理回收利用废弃食用油脂,可替代石油资源作为生产生物柴油、表面活性剂、精细化学品和大宗化学品的重要原料;相反再次食用,则是危害人类身体健康和生存环境的污染物。为此,列举了废弃食用油脂的危害,同时指出了其有益的化工利用方式:制备无磷洗衣粉、制备生物破乳剂、制备脂肪酸、制备脂肪酸甲酯(生物柴油)。 相似文献
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阳离子交换树脂催化油脂副产物制备生物柴油的动力学研究 总被引:2,自引:1,他引:1
以棕榈油脱臭馏出物(PODD)和无水甲醇为原料,强酸性阳离子交换树脂为固体酸催化剂,在自制的固定床反应器中进行酯化反应,合成了脂肪酸甲酯(生物柴油)。考察了反应温度、催化反应时间、物料摩尔比对游离脂肪酸转化率的影响。实验结果表明,适宜的反应条件为:反应温度333.15K、催化反应时间56.28min、甲醇与PODD的摩尔比17.25,在此条件下游离脂肪酸转化率为81.66%。同时提出了固定床脂肪酸催化酯化反应的动力学模型,根据实验数据拟合得到动力学参数,酯化反应的活化能为47.761kJ/mol,指数前因子为59.641L/(kmol.min)。该模型能较好地描述固定床脂肪酸催化酯化的反应过程。 相似文献
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In the present research work, a non-edible oil source Cucumis melo var. agrestis(wild melon) was systematically identified and studied for biodiesel production and its characterization. The extracted oil was 29.1% of total dry seed weight. The free fatty acid value of the oil was found to be 0.64%, and the single-step alkaline transesterification method was used for conversion of fatty acids into their respective methyl esters. The maximum conversion efficiency of fatty acids was obtained at 0.4 wt% Na OH(used as catalyst), 30%(methanol to oil, v/v) methanol amount, 60 ℃ reaction temperature,600-rpm agitation rate and 60-min reaction time. Under these optimal conditions, the conversion efficiency of fatty acid was 92%. However, in the case of KOH as catalyst, the highest conversion(85%) of fatty acids was obtained at 40%methanol to oil ratio, 1.28 wt% KOH, 60 ℃ reaction temperature, 600-rpm agitation rate and 45 min of reaction time.Qualitatively, biodiesel was characterized through Fourier transform infrared spectroscopy(FTIR) and gas chromatography and mass spectroscopy(GC–MS). FTIR results demonstrated a strong peak at 1742 cm~(-1), showing carbonyl groups(C=O)of methyl esters. However, GC–MS results showed the presence of twelve methyl esters comprised of lauric acid, myristic acid, palmitic acid, non-decanoic acid, hexadecanoic acid, octadecadienoic acid and octadecynoic acid. The fuel properties were found to fall within the range recommended by the international biodiesel standard, i.e., American Society of Testing Materials(ASTM): flash point of 91 ℃, density of 0.873 kg/L, viscosity of 5.35 c St, pour point of-13 ℃, cloud point of-10 ℃, total acid number of 0.242 mg KOH/g and sulfur content of 0.0043 wt%. The present work concluded the potential of wild melon seed oil as excellent non-edible source of bioenergy. 相似文献