均相催化废餐饮油制备生物柴油工艺研究

考察了用浓H2SO4及NaOH催化废餐饮油和甲醇反应制备生物柴油的反应条件.结果表明,用NaOH作催化剂的2步酯交换法制备生物柴油时,预处理过程的最佳条件为:醇油质量比为0.4,催化剂H2SO4用量占原料油的质量分数为2.0%,反应时间为0.5 h,反应温度为65℃.主反应的最佳条件为:醇油质量比为0.25,催化剂用量为0.8%,反应温度为65℃,反应时间为1 h.在上述工艺条件下,产品生物柴油的收率可达95%,其各项性能实测值均达到欧洲生物柴油的标准要求.     

甲醇-大豆油二组分物系临界参数的计算及其应用

对甲醇-大豆油二组分物系的临界参数采用 Lyderson 基团贡献法和 Prausnitz 混合规则进行计算,计算临界温度的平均误差为2%结合甲醇-大豆油二组分物系临界参数的计算结果,对由甲醇和大豆油制生物柴油的管式反应器中的流体相态进行了分析。管式反应器沿轴向依次分为扩散区、互溶区和分相区;反应温度影响甲醇和大豆油混合状况和相态的轴向分布,进而影响生物柴油收率;反应压力影响物系的密度和油脂在甲醇中的溶解度,从而影响相态的轴向分布和生物柴油收率;利用管式反应器制生物柴油较适宜的操作条件在物系的临界点附近。     

Porcine pancreatic lipase immobilized on polysiloxane–polyvinyl alcohol hybrid matrix: catalytic properties and feasibility to mediate synthesis of surfactants and biodiesel

Polysiloxane–polyvinyl alcohol hybrid matrix was prepared by a sol–gel technique and its capacity to bind porcine pancreatic lipase investigated. The loading of 250 units g^?1 support was shown to be effective, resulting in an immobilized lipase with high catalytic activity. Both free and immobilized lipases were characterized by determining the activity profile as a function of pH, temperature, substrate concentration and thermal stability. Application of the immobilized lipase in non‐conventional biocatalysis for the synthesis of surfactants and biodiesel was also analyzed. Production of sugar fatty acid esters was found to be dependent on the carbohydrate and the highest molar conversion (50% in 3–4 h of reaction) was achieved for substrates containing fructose and lauric or oleic acids. Biodiesel synthesis from babassu oil and ethanol, propanol or butanol was feasible and regardless of the kind of alcohols, results revealed that the immobilized PPL could efficiently convert triglycerides to fatty acid alkyl esters attaining yields varying from 75 to 95%. Copyright © 2007 Society of Chemical Industry     

加压催化合成生物柴油的酯交换反应动力学

在工业甲醇与粗菜籽油摩尔比为6:1、KOH催化剂质量分数0.5%(基于菜籽油)的条件下,在500mL高压搅拌反应釜中进行加压催化合成生物柴油的酯交换反应,研究了在反应温度高于甲醇常压沸点(64.5℃)时酯交换反应的动力学,采用最小二乘法回归实验数据,获得幂函数形式的加压催化条件下粗菜籽油与工业甲醇酯交换反应的宏观动力学模型。实验结果表明,酯交换反应的反应级数为1.86,反应活化能为23.493kJ/mol,与文献值相近,频率因子为2782min-1。F检验表明,幂函数模型与实验数据吻合良好,说明该宏观动力学模型可用于描述加压催化下粗菜籽油与工业甲醇的酯交换反应。     

离子液体催化麻疯树果油制备生物柴油

通过两步法制备了一种酸性功能化离子液体[BSO3HMIM]HSO4,以麻疯树果油为原料,考察了离子液体[BSO3HMIM]HSO4催化下,甲醇和麻疯树果油酯交换制备生物柴油的性能。结果表明,当醇油摩尔比为12,离子液体[BSO3HMIM]HSO4用量为6%,反应时间为5h,反应温度为120℃时,生物柴油收率可达93.4%,且离子液体[BSO3HMIM]HSO4具有较好的重复使用能力,重复使用6次后,生物柴油的收率没有明显降低。     

Rapid Characterization of Fatty Acids in Oleaginous Microalgae by Near-Infrared Spectroscopy

The key properties of microalgal biodiesel are largely determined by the composition of its fatty acid methyl esters (FAMEs). The gas chromatography (GC) based techniques for fatty acid analysis involve energy-intensive and time-consuming procedures and thus are less suitable for high-throughput screening applications. In the present study, a novel quantification method for microalgal fatty acids was established based on the near-infrared spectroscopy (NIRS) technique. The lyophilized cells of oleaginous Chlorella containing different contents of lipids were scanned by NIRS and their fatty acid profiles were determined by GC-MS. NIRS models were developed based on the chemometric correlation of the near-infrared spectra with fatty acid profiles in algal biomass. The optimized NIRS models showed excellent performances for predicting the contents of total fatty acids, C16:0, C18:0, C18:1 and C18:3, with the coefficient of determination (R²) being 0.998, 0.997, 0.989, 0.991 and 0.997, respectively. Taken together, the NIRS method established here bypasses the procedures of cell disruption, oil extraction and transesterification, is rapid, reliable, and of great potential for high-throughput applications, and will facilitate the screening of microalgal mutants and optimization of their growth conditions for biodiesel production.     

生物质结渣固体碱催化剂制备生物柴油

采用经气化炉烧结的生物质结渣为固体碱催化剂,催化油脂转化合成生物柴油.对固体碱催化剂进行表征,并考察物质的量之比、反应温度、反应时间和催化剂用量对反应的影响.结果表明:生物质结渣固体碱催化剂主要成分(按质量分数计)为SiO2(40％～60％)、CaO(10％～20％)、K2O(10％～15％)、MgO(≤10％)、Al...     

白云石非均相催化合成生物柴油的工艺研究

以大豆油、甲醇为原料,研究了通过白云石催化酯交换反应制取生物柴油的工艺的条件。用气相色谱-质谱分析法,并对反应温度、醇油摩尔比、反应时间、催化剂的用量及催化剂粒径进行考察,得出最佳合成条件为:反应温度65℃、反应时间2h、醇油摩尔比7:1,催化剂用量2%,催化剂粒径为80～150目,在此条件下得到生物柴油转化率为77.36%。     

亚临界甲醇中麻疯树油制备生物柴油的研究

对麻疯树油在催化剂对甲苯磺酸作用下与亚临界甲醇反应制备脂肪酸甲酯(生物柴油)进行了研究。结果表明在反应温度170℃、醇油摩尔比40:1、催化剂用量占油重的0.75%和反应时间30 m in的条件下,反应产物中脂肪酸甲酯含量可达93%以上。制备的生物柴油,各项指标与柴油相似。主要性能指标,符合ASTMPS121-99(USA)和0#矿物柴油标准。     

酯交换反应制备生物柴油催化剂的研究进展

生物柴油是一种环境友好型的可再生资源,本文介绍了生物柴油的制备技术,并综述了采用酯交换反应制备生物柴油所使用的催化剂的研究进展,简述了各种催化剂的优缺点。