双核离子液体作用下生物柴油的制备及成分分析

Preparation and Component Analysis of Biodiesel Catalyzed by Functionalized Dication Ionic Liquid

采用超声波辅助的方式制备了新型的酸性双咪唑甲磺酸离子液体,并通过三油酸甘油酯的酯交换反应考查其催化活性及优化实验反应条件,然后将其应用于烤鸭废弃油中以制取生物柴油,对其产物采用气质联用仪(CG-MS)进行了分析。结果表明:在该离子液体作用下,酯交换反应可以在温和的条件下高效地完成,三油酸甘油酯的酯交换产率最高可达95.3%,双咪唑间碳链长短对催化活性影响不明显;催化剂经循环使用6次以后,油酸甲酯产率仍然保持在81%左右。废弃油酯交换制取生物柴油最高产率可达93.9%,且GC-MS检测结果表明生物柴油中脂肪酸甲酯的总含量高达96.9%,其中饱和脂肪酸甲酯含量接近22%,而酯交换未完全的脂肪酸单甘油酯仅0.83%。因此,双咪唑甲磺酸型离子液体能高效催化餐饮废油制备生物柴油。

The sulfonate dication ionic liquid was synthesized through the two-step method under the ultrasonication condition,and its catalytic activity was examined.The yield of biodiesel from the transesterification of glycerol trioleate with methanol could reach 95.3% under the optimal condition,waste cooking oil could be effectively converted into biodiesel（ 93. 9%） under the same condition. The catalysts could be recycled 6 times with a little loss of catalytic activity in every recycle and the yield of biodiesel still retained 81%.Furthermore,according to the results of GC-MS,the content of fatty acid methyl esters was 96.9%,including about 22% of saturated fatty acid methyl esters,but only 0.83% of monoglycerids. Therefore,the sulfonate dication ionic liquid has a higher catalytic activity in the synthesis of biodiesel from waste cooking oils.