废弃植物油酯交换制备生物柴油

Transesterification of Waste Rapeseed Oil to Biodiesel

培养学生的绿色环保意识和可持续发展意识是应用化学专业本科人才培养方案的基本要求之一。目前实验教学中培养学生绿色环保和可持续发展意识的实验项目较少,针对这一问题,在综合化学实验中增加本新创实验项目。实验以废弃菜籽油和甲醇为原料,氢氧化钠和氯化胆碱为催化剂,生成的副产物甘油与氯化胆碱原位形成低共熔体系,与产品形成液-液两相,促使反应正向进行,简化后处理,提高产品纯度和产率。GC-MS(Gas chromatographymassspectrometer)结果表明,产品纯度大于99%,产率接近85%。分离出的低共熔体系可循环使用。燃烧热测试表明其热值与矿物柴油相当。实验使用的原料安全低毒,涉及基础有机化学实验、物理化学燃烧热测定、分析化学等多门基础实验课程的基本操作和表征,适合作为应用化学专业三年级综合化学实验教学实验项目的补充。通过本实验,有利于让学生更加系统地理解和掌握化学实验技术,培养其主动探索精神,锻炼其综合实践能力,同时,将绿水青山、环保低碳、变废为宝等课程思政理念融于综合化学实验教学。

The undergraduate talent training plan for applied chemistry and other majors includes the use of the principles and methods of chemistry needed to realize recycling.However,there are few comprehensive experiments on recycling in the training plan.In this experiment,waste rapeseed oil and methanol are used as starting materials and sodium hydroxide and choline chloride as catalysts.The generated byproduct glycerin combines with choline chloride to form an eutectic system in situ,which is immiscible with the product/substrate phase,facilitating the fast removal of glycerin from the reaction system,and thus,promoting the reaction forward,simplifying the post-treatment process and improving the purity of the product.Moreover,the separated eutectic system can be used directly for another run.In addition,the calorific value of biodiesel is comparable to that of petrodiesel according to the results of measurements of the heat of combustion.Generally,the chemical reagents used are low-toxic and the experiment is composed of a series of fundamental operations in organic,physical and analytical chemistry experiments,and is therefore a promising experiment candidate for a comprehensive chemistry laboratory for undergraduates.This experiment also helps students to systematically understand and master the technology used and to train their initiative and exploration spirit and comprehensive practical ability.Besides,it is beneficial to integrate the ideology of environmental protection,low carbon usage and recycling into comprehensive chemistry experiment teaching.