摘要
为寻找高活性催化剂,制备了5种甲基咪唑类硫酸氢盐离子液体([CnMIm]HSO4,n=0,2,4,6,8),测定了其酸性强度,研究了其酯化催化性能。结果表明:在这5种离子液体中,1-己基-3-甲基咪唑硫酸氢盐([C6MIm]HSO4)催化酯化反应效果最佳,其反应条件是:反应时间14 h,反应温度为90℃,n(甲醇):n(油酸)=2.5∶1,催化剂用量为酸重的8%,油酸甲酯的产率可达91%以上.产物易于纯化,离子液体重复使用了6次仍显示出良好的催化效果.在温和的实验条件下,[C6MIm]HSO4对油酸的酯化反应显示出良好的催化活性.
Five acidic ionic liquids with an hydrogen sulfate acid group were synthesized （[Cn MIm] HSO4 ,n=0,2,4,6,8）. Their acidity was studied. Their application in esterification utilizing oleic acid and methanol was explored. The experimental results showed 1-hexyl-3-methyl-Imidulium hydrogen sulphate（[C6MIm]HSO4） was the best catalyst of acidic ionic liquid in esterification. Under optimal esterification conditions ： n（methanol） ： n （ oleic acid） = 2. 5 ： 1, m （ oleic acid）：m〈[C6MIm]HSO4） = 1 ： 0.08, temperature 90 ℃ and time 14 h, mass fraction of fatty acid methyl ester could reach more than 91%. The ionic liquids were stable and could be reused. Methyl oleate was separated from raw material easily; even if ionic liquid was reused beyond 6 times,the conversion of esterification did not decrease.
出处
《武汉工程大学学报》
CAS
2009年第1期25-28,共4页
Journal of Wuhan Institute of Technology
基金
武汉市晨光计划(200750731280)资助项目
关键词
酸性离子液体
制备
催化性能
油酸
酯化反应
acid ionic liquids
synthesize
catalyze
oleic acid
esterification
