阳离子交换树脂催化合成异丁酸正丁酯

以异丁酸和正丁醇为原料,阳离子交换树脂(NKC-9)为催化剂,合成了异丁酸正丁酯。考察了醇酸摩尔比、催化剂用量、反应时间等因素对反应的影响,并测定了动力学数据。通过实验得到了较佳制备工艺条件:n(正丁醇)∶n(异丁酸)=1.4∶1,NKC-9催化剂用量为异丁酸和正丁醇总质量的4%,反应温度≤125℃,反应时间2.0h,在该条件下,异丁酸的转化率达97.6%,催化剂重复使用5次后,异丁酸的转化率为96.4%。并建立了该酯化反应的表观动力学模型。

Synthesis and Kinetics of n-Butyl Isobutyrate with Cation Exchange Resin as Catalyst

The synthesis of n-butyl isobutyrate from isobutyric acid and n-butyl alcohol with the NKC-9 cation exchange resin as catalyst was investigated.The effect of reaction conditions,such as mole ratio of n-butyl alcohol to isobutyric acid,NKC-9 catalyst dosage and reaction time were also investigated.The kinetic data of this system were measured in a batch reactor.The optimum reaction conditions were found as:mole ratio,n(n-butyl alcohol):n(isobutyric acid)=1.4:1;NKC-9 cation exchange resin as catalyst dosage,4.0%(the mass of catalyst relative to the total mass of isobutyric acid and n-butyl alcohol);reaction temperature,≤125 ℃;reaction time,2.0 h.The conversion of isobutyric acid by the process achieves 97.6%,and the activity of catalyst can be maintained at 96.4% conversion after being used 5 times.At the same time,the apparent kinetic model of esterification was established.