共查询到19条相似文献,搜索用时 171 毫秒
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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
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《化学工业与工程技术》2017,(6):20-23
以浓硫酸和三乙胺为原料制备了酸性离子液体硫酸氢铵盐[Et3NH][HSO4],作为催化剂用于亚麻油与甲醇酯交换反应制备生物柴油。考察了催化剂添加量、醇油摩尔比、反应温度和反应时间等因素对酯交换产品收率的影响。试验结果表明:硫酸氢铵盐离子液体对酯交换反应有很高的催化活性,在甲醇与亚麻油摩尔比为8∶1、催化剂占原料油质量分数6%、反应温度120℃和反应时间5 h的优化条件下,酯交换产品收率可达90%以上。产物中含有十五酸甲酯、软脂酸甲酯等长链酯类物质,与生物柴油的化学组成分相似,说明离子液体硫酸氢铵盐能够催化制备生物柴油。 相似文献
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酶促泔水油生产生物柴油条件的研究 总被引:2,自引:0,他引:2
以泔水油资源转化为宗旨,利用中性脂肪酶催化泔水油与甲醇反应制备生物柴油。通过50g泔水油正交实验获得最佳转酯化反应条件:油醇摩尔比1∶3,油酶质量比1∶1,温度45℃,油溶剂质量比1∶0.6,反应时间10h后,生物柴油产率可达89.7%以上。对生物柴油密度、黏度、馏程、凝固点、硫含量、残碳、十六烷值等多项指标进行检测,油品的质量符合我国生物柴油的标准。在优化条件的基础上进行10L和50L反应釜实验,10h生物柴油的产率达到80%以上。 相似文献
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固定化脂肪酶催化制备香叶树籽生物柴油研究 总被引:3,自引:0,他引:3
研究了Novozym 435和Lipozyme TLIM混合脂肪酶催化香叶树籽油制备生物柴油,2种酶按1:3质量比混合使用时,既可提高反应转化率,又可降低酶的使用成本.应用响应面优化法确定了固定化酶催化香叶树籽生物柴油的最优工艺参数,采用叔丁醇作为反应体系的溶剂,最优反应条件为反应温度38.5℃、甲醇与油摩尔比4:1、叔丁醇与油体积比1:1.5、酶用量为油质量的4%,此时反应转化率达90.09%.分析表明香叶树籽油的甘油三酯主要由短链脂肪酸甘油酯组成,生物柴油中原油的甘油三酯已完全转变成脂肪酸甲酯. 相似文献
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从废弃油脂生物柴油中分离不饱和脂肪酸甲酯 总被引:5,自引:1,他引:4
以废弃油脂制生物柴油为原料,以95%醇为溶剂,采用尿素包合法提取不饱和脂肪酸甲酯,为生物柴油联产具有高附加值化工产品打下基础.重点考察了尿素用量、溶剂用量、包合时间和包合温度对不饱和脂肪酸甲酯分离效果的影响.结果表明,尿素包合法从生物柴油中分离不饱和脂肪酸甲酯的适宜工艺条件为:尿素,生物柴油质量比为1.4~1.7,溶剂/生物柴油质量比为4.6~6.0,包合温度为10℃,包合时间为18 h.在适宜条件下,不饱和脂肪酸甲酯含量可达93.5%,收率可达55.8%. 相似文献
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微波辐射酸催化喜树种子油制备生物柴油工艺 总被引:5,自引:0,他引:5
研究了在微波辐射条件下硫酸催化酯交换反应转化喜树种子油制备生物柴油的工艺,同时采用HPLC分析了生物柴油产品中主要脂肪酸甲酯成分及其质量分数。通过实验考察了醇油摩尔比、反应时间、反应温度、催化剂加入质量分数对反应的影响,并得出了在微波辐射下硫酸催化喜树种子油制备生物柴油的最佳工艺条件:醇油摩尔比15∶1、微波辐射时间40 min、反应温度70℃、催化剂加入质量分数(与原料油)3%,转化率可达95%以上。结果表明,与传统硫酸催化酯交换反应相比,该方法具有催化剂加入质量分数少、反应温度低、时间短和转化率高等优点,对工业化制备生物柴油提供了科学参考价值。 相似文献
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The non-edible crude rice bran oil was extracted from white rice bran, and then was catalyzed by immobilized lipase for biodiesel production in this study. The effects of water content, oil/methanol molar ratio, temperature, enzyme amount, solvent,number of methanol added times and two-step methanolysis by using Candida sp. 99-125 as catalyst were investigated. The optimal conditions for processing 1 g rice bran oil were: 0.2 g immobilized lipase, 2 ml n-hexane as solvent, 20% water based on the rice bran oil mass, temperature of 40 °C and two-step addition of methanol. As a result, the fatty acid methyl esters yield was 87.4%. The immobilized lipase was proved to be stable when it was used repeatedly for 7 cycles. 相似文献
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Enzymatic conversion of waste edible oil to biodiesel fuel in a fixed-bed bioreactor 总被引:9,自引:0,他引:9
Yomi Watanabe Yuji Shimada Akio Sugihara Yoshio Tominaga 《Journal of the American Oil Chemists' Society》2001,78(7):703-707
The conversion of waste edible oil to biodiesel fuel in a fixed-bed bioreactor was investigated. Three-step methanolysis of
waste oil was conducted using three columns packed with 3 g of immobilized Candida antarctica lipase. A mixture of waste oil and 1/3 molar equivalent of methanol against total fatty acids in the oil was used as substrate
for the first-step reaction, and mixtures of the first- and second-step eluates and 1/3 molar equivalent of methanol were
used for the second- and third-step reactions, respectively. Ninety percent of waste oil was converted to the corresponding
methyl esters (ME) by feeding substrate mixtures into the first, second, and third reactors at flow rates of 6, 6 and 4 mL/h,
respectively. We also attempted one-step methanolysis of waste oil. When a mixture of waste oil and 90% ME-containing eluate
(1∶3, wt/wt) and an equimolar amount of methanol against total fatty acids in the waste oil was fed into a reactor packed
with 3 g of immobilized C. antarctica lipase at a flow rate of 4 mL/h, the ME content in the eluate reached 90%. The immobilized biocatalyst could be used for
100 d in the two reaction systems without significant decrease in its activity. Waste oil contained 1980 ppm water and 2.5%
free fatty acids, but these contaminants had little influence on enzymatic production of biodiesel fuel. 相似文献
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高酸值山苍籽核仁油合成生物柴油 总被引:1,自引:1,他引:0
以高酸值山苍籽核仁油(LCKO)为原料,采用二步法合成生物柴油(BD),即先用固体酸SO42-/ZrO2为催化剂进行酯化反应降低酸值,再用相转移催化剂十六烷基三甲基溴化铵(CTMAB)/NaOH催化进行酯交换反应。酯化反应的最佳条件:质量分数4%的SO42-/ZrO2,醇油摩尔比10∶1,温度68℃,反应时间4h。原油酸值降到2.52mg/g;酯交换反应的最佳条件:温度25℃,质量分数0.5%的CTMAB,1%的NaOH,醇油摩尔比6∶1,反应15min。原油酯交换率达到97.6%。此工艺无酸化废水排放,不需耐酸设备,所需时间短,能耗少,成本低。以山苍籽核仁油为原料合成生物柴油,致力于找到一条经济的、绿色的生物柴油合成路线。 相似文献
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Chi-Yang Yu Liang-Yu Huang I-Ching Kuan Shiow-Ling Lee 《International journal of molecular sciences》2013,14(12):24074-24086
Biodiesel, a non-toxic and biodegradable fuel, has recently become a major source of renewable alternative fuels. Utilization of lipase as a biocatalyst to produce biodiesel has advantages over common alkaline catalysts such as mild reaction conditions, easy product separation, and use of waste cooking oil as raw material. In this study, Pseudomonas cepacia lipase immobilized onto magnetic nanoparticles (MNP) was used for biodiesel production from waste cooking oil. The optimal dosage of lipase-bound MNP was 40% (w/w of oil) and there was little difference between stepwise addition of methanol at 12 h- and 24 h-intervals. Reaction temperature, substrate molar ratio (methanol/oil), and water content (w/w of oil) were optimized using response surface methodology (RSM). The optimal reaction conditions were 44.2 °C, substrate molar ratio of 5.2, and water content of 12.5%. The predicted and experimental molar conversions of fatty acid methyl esters (FAME) were 80% and 79%, respectively. 相似文献
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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
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近年来由于化石燃料的全球性短缺、原油价格的过度上涨和环境问题的加剧致使生物柴油的生产迅速增长。生物柴油生产的关键反应是化学或生物催化的转酯反应,酶催化的转酯反应与化学催化相比有相对节能、副产物甘油易回收及适合高含量游离脂肪酸油脂作为底物等明显优势。本文综述了固定化脂肪酶生产生物柴油的现状及最新进展,包括生物柴油的原料、脂肪酶的来源、酶的固定化技术、甲(乙)醇及甘油对脂肪酶的失活作用,展望了固定化脂肪酶生产生物柴油的未来前景。 相似文献
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《中国化学工程学报》2014,22(11-12):1215-1219
The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractions. Gas chromatography showed that free fatty acid content in camphor tree seed oil was 1.88%, and the main fatty acids were capric acid (53.4%) and lauric acid (38.7%). With immobilized lipase Candida sp. 99–125 as catalyst, several important factors for reaction conditions were examined through orthogonal experiments. The optimum conditions were obtained: water content and enzyme loading were both 15% with a molar ratio of 1:3.5 (oil/ethanol), and the process of alcoholysis was in nine steps at 40 °C for 24 h, with agitation at 170 r·min− 1. As a result, the medium-chain biodiesel yield was 93.5%. The immobilized lipase was stable when it was used repeatedly for 210 h. 相似文献