N-甲基咪唑硫酸氢盐离子液体催化合成柠檬酸三丁酯

Synthesis of Tributyl Citrate Catalyzed by Ionic Acid Catalyst

采用N-甲基咪唑硫酸氢盐离子液体为催化剂,进行柠檬酸三丁酯的合成反应。在催化剂用量为反应物总质量15%的条件下,考察了原料配比、反应时间对反应物酯化率的影响。得到了最佳反应条件:丁醇与柠檬酸物质的量之比为6∶1,甲苯为带水剂,反应温度110℃,反应时间7 h。在此条件下的柠檬酸酯化率大于97%。催化剂可重复使用10次以上。所得产品柠檬酸三丁酯结构通过FT-IR、1H NMR确证。用离子液体合成的柠檬酸三丁酯增塑剂色度值远低于市售同类产品,酸值、水分两者相近,产品质量优于市售产品。

Synthesis of Tributyl Citrate under the catalysis of ＋-was investigated.The optimum reaction conditions were as follows：15% catalyst based on the reactants,n（butyl alcohol） ∶ n（citric acid）=6 ∶ 1,cyclohexane as water-carrying agent,reaction temperature 110 ℃,and reaction time 7 h.Under these conditions,the yield of product was above 97 %.The catalyst can be reused 10 times.The structure of product was characterized by FT-IR、 1 H NMR.The quality of Tributyl Citrate synthesized in this paper is superior to general commercial products with low chrominance value,similar acid value and moisture.