摘要
以制备的1-丙基磺酸-3-甲基咪唑对甲苯磺酸([MIMPS][C7H7O3S])离子液体为催化剂结合自行设计的反应装置,对高酸值酸化油进行酯化降酸试验,考察了甲醇通入量、催化剂用量、反应温度和反应时间等因素对酸化油转化率和预酯化油酸值的影响,并考察了催化剂的重复使用性能。对离子液体的红外光谱分析结果表明制备的离子液体符合反应产物化学结构特征;热稳定性分析表明该离子液体在200℃以下具有较好的稳定性。通过单因素与正交试验确定最佳工艺条件:酸化油50 g、甲醇通入量0.99 mL/min、催化剂用量(以酸化油质量计)2.5%、反应时间3 h、反应温度105℃,在此条件下转化率可达98.42%,酸值由120 mg/g变为1.9 mg/g。油脂酯化降酸后酸值达到后续酯交换制备生物柴油酸值小于4 mg/g的指标要求。催化剂重复使用9次,转化率仍保持在75%以上,说明酸性离子液体催化剂对高酸值原料酯化降酸有很好的催化活性且具有良好的稳定性。
Using a self-made 1-propylsulfonic acid-3-methylimidazolium-p-toluenesulfonic acid ionic liquid([MIMPS][C7H7O3S])as catalyst,the esterification and deacidification of acidified oil with high acid value was carried out with self-designed equipment as reaction device.The effects of amount of methanol,amount of catalyst,reaction temperature,reaction time on the conversion of acidified oil and acid value of pre-esterified oil were investigated,and then the recyclability of catalyst was studied.The infrared spectrum analysis results showed that the synthesized ionic liquid accorded with its structural characteristics.The ionic liquid had good thermal stability under 200℃.The optimum process conditions determined by single factor and orthogonal tests were as follows:acidified oil 50 g,methanol 0.99 mL/min,catalyst dosage 2.5%,reaction time 3 hours,reaction temperature 105℃.Under these conditions,the conversion rate could reach 98.42%,and the acid value changed from 120 mg/g to 1.9 mg/g.After esterification,the acid value of the acidified oil met the requirement of the acid value for preparing biodiesel(less than 4 mg/g).As the ionic liquid catalyst was reused for 9 times,the conversion rate remained above 75%,indicating that[MIMPS][C7H7O3S]ionic liquid catalyst had good catalytic activity and good stability for deacidification and esterification of acidified oil with high acid value.
作者
李惠文
杨铃梅
吕鹏梅
王忠铭
苗长林
袁振宏
LI Huiwen;YANG Lingmei;LYU Pengmei;WANG Zhongming;MIAO Changlin;YUAN Zhenhong(Guangzhou Institute of Energy Conversion,Chinese Academy of Sciences,Key Laboratory of Renewable Energy, Chinese Academy of Sciences,Guangdong Key Laboratory of New and Renewable Energy Research and Development,Guangzhou 510640,China)
出处
《生物质化学工程》
CAS
北大核心
2020年第4期9-15,共7页
Biomass Chemical Engineering
基金
国家重点研发计划资助项目(2017YFD0601003)
国家自然科学基金资助项目(51606201)。
关键词
生物柴油
酯化反应
酸化油
降酸
离子液体
biodiesel
esterification
acidified oil
deacidification
ionic liquid
