摘要
以阳离子交换树脂(NKC-9)为催化剂,乳酸和乙醇为原料,采用0.4nm分子筛吸附脱水技术合成乳酸乙酯。考察了n(乙醇)∶n(乳酸)、NKC-9用量和反应时间等因素对反应的影响,确定最佳酯化反应工艺条件为:n(乙醇)∶n(乳酸)=1.2∶1、w(NKC-9)=5%(以乙醇和乳酸总质量计),回流温度,反应时间4.0h;在该条件下乳酸的转化率达到97.9%。催化剂重复使用4次后,乳酸的转化率仍可达到90%以上。研究了反应动力学,确定反应级数为二级,表观活化能为52.94kJ/mol。
Synthesis of ethyl lactate from lactic acid and ethanol catalyzed by cation exchange resin（NKC-9）was studied under adsorption dehydration with 0.4nm molecular sieve.The effects of different reaction conditions such as n（ethanol）∶n（lactic acid）,amount of NKC-9and reaction time were studied.The results showed that the optimum esterfication process conditions were as follows：n（ethanol）∶n（lactic acid）=1.2∶1[w（NKC-9）=5%]（total weight of ethanol and lactic acid）,under reflux conditon and reaction time of 4.0h.Under the above conditions,the conversion rate of lactic acid was up to 97.9%.The conversion rate of lactic acid was still over 90%,after the catalyst being used for 4times.The results showed that the synthesis of ethyl lactate was a second-order reaction,and the apparent activation energy was 52.94kJ/mol.
出处
《化学世界》
CAS
CSCD
2016年第10期631-634,共4页
Chemical World
关键词
乳酸乙酯
分子筛
吸附脱水
动力学
ethyl lactate
molecular sieve
absorption dehydration
kinetics
