甲基磺酸铜催化合成柠檬酸三(2-乙基己基)酯的研究

Study on catalytic synthesis of tri(2-ethylhexyl) citrate with copper methanesulfonate

研究了以甲基磺酸铜催化柠檬酸和2-乙基己醇的酯化反应，考察了反应温度、催化剂用量、醇酸摩尔比等对反应的影响。结果表明，甲基磺酸铜催化合成柠檬酸三（2-乙基己基）酯的最佳反应条件为：n（2-乙基己醇）：n（柠檬酸）=1．08：0．3，催化剂用量0．30％（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-乙基己基）酯收率在98％以上；反应结束后，催化剂通过简单的相分离，即可重复使用，重复使用5次，其催化活性元明显下降，产品收率仍可达到90％以上。

Copper methanesulfonate was synthesized and was 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 yield can be over 98% under the optimum conditions that molar ratio of 2-ethylhexanol to citric acid is 1.08 ： 0.3 ;amount of catalyst is 0.30% （ molar percentage of citric acid） and reaction temperature is 120 - 130 ℃ ,reaction pressure is 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%.