甲基磺酸亚铈催化合成柠檬酸三(2-乙基)己酯的研究

Study on Catalytic Synthesis of Tri(2-ethylhexyl) Citrate with Cerous Methanesulfonate

合成了甲基磺酸亚铈,研究了以甲基磺酸亚铈催化柠檬酸和2-乙基己醇的酯化反应,考察了反应温度、催化剂用量、醇酸摩尔比等因素对反应结果的影响,对合成的产品进行了红外光谱分析。实验结果表明,甲基磺酸亚铈催化合成柠檬酸三（2-乙基）己酯的最佳反应条件为：n（2-乙基己醇）∶n（柠檬酸）=3.60∶1,催化剂用量0.25%（以酸的物质的量计）,反应温度120℃-130℃,负压操作。在最佳反应条件下,柠檬酸三（2-乙基）己酯收率在98.0%以上。反应结束后,催化剂通过简单的相分离即可重复使用。甲基磺酸亚铈重复使用5次后,其催化活性无明显下降,产品收率仍可达到90%以上。

Cerous methanesulfonate was synthesized and used as the catalyst in the esterification of citric acid with 2-ethylhexanol.The effects of reaction temperature,amount of catalyst and alcohol/acid molar ratio have been investigated.The products were analyzed by means of FT-IR.The yield can be over 98.0% under the optimum conditions that molar ratio of 2-ethylhexanol to citric acid,3.60∶1;amount of catalyst,0.25%（molar percentage of citric acid） and reaction temperature,120℃～130℃,reaction pressure： vacuum.The catalyst can be reused by simple phase-separation after reaction.It is used repeatedly for 5 times without obvious loss of activity and with the yield still over 90.0%.