亚临界CO_2中邻甲酚羧基化合成邻甲基水杨酸.pdf

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2012年第31卷第5期
CHEMICAL INDUSTRY AND ENGINEERING PROGRESS
1137
研究开发
超/亚临界CO2中邻甲酚羧基化合成邻甲基水杨酸
张平,徐明仙2,俞景译,林春绵
(江工业大学生物与环境工程学院,浙江杭州310014:2杭州职业技术学院临江学院,浙江杭州310018)
摘要:在超/亚临界CO2中合成邻甲基水杨酸,对探索其绿色合成和CO2的资源化利用有重要意义。本实验以
邻甲酚为原料,考察了无水K2CO3、无水Na2CO3等催化剂的活性,选取催化效果最好的无水K2CO在超/亚临
界CO2中一步法直接催化合成邻甲基水杨酸。在反应时间1~6h、催化剂相对投加量mg,co/ /nocresol为0.05
1.25、反应温度130~270℃、反应压力4~14MPa的条件下对邻甲酚在超/亚临界CO2中的羧基化反应进行
了研究。结果表明:邻甲酚的转化率与产物收率随反应时间的廷长均出现先增加的趋勢,不同的是转化率最
后趋于稳定,产物收率则略有减少;邻甲酚的转化率与产物收率随催化剂相对投加量的增加先快速増加然后趋
缓,随反应温度、反应压力的増加先增加后减少。较佳的实验条件为:反应时间3h、催化剂相对投加量0.5、
反应温度190℃、反应压力8MPa,此时,邻甲酚转化率可达19.7%,邻甲基水杨酸收率可达17.5%。此外,提
出了超/亚临界CO2中邻甲酚羧基化反应可能存在的机理。
关键词:超/亚临界CO2;邻甲盼;邻甲基水杨酸;一步法合成;无水K2CO3
中图分类号:TQ460.3
文献标志码:A
文章编号:1000-6613(2012)05-1137~06
Experimental study on the synthesis of 3-methyl salicylic acid from carboxylated
o-cresol in supercritical or subcritical carbon dioxide
ZHANG Ping XU Mingxian, YU Jingyi, LN Chunmian
(College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014
thejiang, China; Hangzhou Vocational and Technical College, Hangzhou 310018, Zhejiang, China)
Abstract: The synthesis of 3-methyl salicylic acid in supercritical or subcritical carbon dioxide has
important meaning for the green synthesis of 3-methyl salicylic acid and resourcization of carbon
dioxide. After comparing the catalytic activity of anhydrous potash, anhydrous sodium carbonate and
so on, anhydrous potash was chosen as the best catalyst to synthesize 3-methyl salicylic acid directl
from o-cresol by one-pot method in supercritical or subcritical carbon dioxide. At the condition of
reaction time from 1-6 hours, catalyst relative dosage( ,cono-crel)from.05-1. 25, reaction
temperature from 130-270 C and reaction pressure from 4-10MPA, o-cresol's carboxylic reaction
was studied in supercritical or subcritical carbon dioxide. The result showed that the conversion
O-cresol and the yield of 3-methyl salicylic acid both increased at first with the increase of time, and
then the conversion became stable, but the yield decreased slightly in the end. The conversion and the
yield increased rapidly at first and then increased slowly with the increase of catalysts relatively
dosage. The conversion and the yield increased rapidly at first but then decreased with the increase of
reaction pressure or reaction temperature. The conversion is about 19. 7% and the yield is about 17. 5%
收稿日期:20111-24;修改稿日期;2012-01-12
第一作者:张平(1986-),男,硕土研究生。联系人:林春绵,教
基金项目:浙江省自然科学基金(Y110158)及浙江省教育厅项目授。E-mailIcm@lu.edu.cn。
(Y200805324)。