【作者】 韩毅；

【导师】 邓宇；

【作者基本信息】 天津科技大学 ， 应用化学， 2008， 硕士

【摘要】 在工业、运输业日益发达的今天,人类对柴油的消耗与日俱增,因此人类面临柴油燃烧后的排放物对大气的污染和石油资源的日益枯竭两大难题。所以,寻找环境污染小,可再生的能源的任务刻不容缓。生物柴油便是这样一种能源,它来自可再生的植物油或动物脂肪,并且能降低空气污染物以及CO₂的排放。目前,世界各国纷纷投入生物柴油的研究和生产中,我国生物柴油的研究虽然刚刚开始,但发展的潜力很大。生物柴油的制备和生产技术多种多样,新的技术方法也是层出不穷。论文首先介绍了K₂O/Al₂O₃固体碱催化剂的制备,其最佳制备条件为:KNO₃的负载量（质量分数）35%,700℃下焙烧5 h。采用傅里叶变换红外光谱、X射线衍射和Hammett滴定对催化剂进行了表征,表征结果显示,KNO₃在Al₂O₃表面分散形成的Al—O—K物种和KNO₃高温分解产物K₂O为反应提供了活性位。研究了KNO₃/Al₂O₃固体碱催化剂的焙烧温度和KNO₃负载量对酯交换反应的影响。论文研究了醇油摩尔比,催化剂含量,微波火力以及微波辐射时间（反应时间）等因素对微波加热条件下的酯交换反应的影响。并分别优化了NaOH催化、KNO₃/Al₂O₃固体碱催化剂催化,微波加热条件下的酯交换反应。采用KNO₃/Al₂O₃固体碱催化剂时,优化的反应工艺参数为:微波输出功率360 W,反应时间35 min,催化剂质量分数6%,甲醇与大豆油的摩尔比13,在该条件下,大豆油的转化率达到97.5%。与水浴加热方式对比,采用微波辐射加热方式,反应时间明显缩短,能耗减少。本论文所制得的生物柴油已经达到美国标准ASTMPS 121-99。更多还原

【Abstract】 Today, with the development of industry and transportation, more and more diesel is consumed. So people have met the air pollution problem caused by the diesel combustion and the problem caused by the absence of petroleum. Therefore, it’s imminent to find an alternative energy which is renewable and has more environmental benefits. Biodiesel is such a kind of fuel which is made from renewable vegetable oil and animal fat, and it can also reduce the air pollutant and the emission of CO2. Now biodiesel attracts the attention of many countries which dive into the research and preparation. Although the biodiesel’s development of China has just begun, the potentiality is great. There are varieties of technologies for biodiesel’s preparation, and some new technologies for biodiesel appear everyday.In this paper, KNO₃/Al₂O₃ solid base catalyst was first prepared. The results show that the catalyst loaded KN03（mass fraction） of 35% on Al₂O₃, after being calcined at 700℃for 5 h, is the optimum catalyst. The catalysts were characterized by means of FTIR, XRD, and Hammett titration methods. The Al-O-K formed on the surface of Al₂O₃ by KNO₃ dispersion, together with the K₂O decomposed by KNO₃ at high temperature, provided the active basic sites for the reaction. The influence of calcination temperature and loading amount of KNO₃ on transesterification were researched. In this paper, the factors of microwave exit power, reaction time, catalyst mass fraction and mole ratio of methanol to soybean oil were studied for the transesterification in the presence of microwave. The transesterification using NaOH and KNO₃/Al₂O₃ solid base catalyst in the presence of microwave were also optimized respectively. When the KNO₃/Al₂O₃ solid base catalyst was employed as the catalyst, the optimized reaction parameters were: microwave exit power of 360 W, reaction time of 35 min, catalyst mass fraction of 6% and mole ratio of methanol to soybean oil of 13. Under the optimized reaction conditions, the conversion of soybean oil can reach 97.5 %. Compared with the method of conventional heating methods, the way using microwave irradiation and solid base catalyst is proved to be faster together with lower energy consumption.The biodiesel prepared had reached the American standards of ASTMPS 121-99.更多还原