化工学报 ›› 2009, Vol. 60 ›› Issue (2): 345-350.

• 催化、动力学与反应器 • 上一篇    下一篇

酸性离子液体作催化剂的硝基苯加氢合成对氨基苯酚

崔咏梅;袁达;王延吉;赵新强   

  1. 河北工业大学绿色化工与高效节能河北省重点实验室
  • 出版日期:2009-02-05 发布日期:2009-02-05

Hydrogenation of nitrobenzene to p-aminophenol using acidic ionic liquid as catalyst

CUI Yongmei;YUAN Da; WANG Yanji;ZHAO Xinqiang   

  • Online:2009-02-05 Published:2009-02-05

摘要:

针对硝基苯催化加氢合成对氨基苯酚(PAP)的过程,提出了Pt/SiO2和新型季铵型Brφnsted酸性离子液体N,N,N-三甲基-N-磺丁基硫酸氢铵([HSO3-b-N(CH3)3]HSO4)构成的双功能催化体系。考察了离子液体浓度、Pt/SiO2用量及操作条件对对氨基苯酚收率和选择性的影响。并与硫酸体系进行了对比。在85℃、4 h、0.4 MPa条件下,硝基苯转化率96.6%,对氨基苯酚的选择性为81.4%,优于Pt/SiO2和硫酸溶液体系。可能的原因是,离子液体增加了硝基苯溶解度,并且抑制了中间产物苯基羟胺的深度加氢。反应后用减压过滤可分离出Pt/SiO2催化剂;滤液经由萃取、减压蒸馏和结晶析出PAP。结果证明,该双功能催化体系重复使用3次,PAP收率没有明显的下降。

关键词:

对氨基苯酚, 硝基苯, 酸性离子液体, Pt/SiO2

Abstract:

A bifunctional catalytic system, Pt/SiO2 and a novel Brφnsted acidic ionic liquid of quaternary ammonium type N,N,N-trimethyl-N-sulfobutyl hydrogen sulfate ([HSO3-b-N(CH3)3]HSO4) was studied for the synthesis of p-aminophenol through the hydrogenation of nitrobenzene.The effect of ionic liquid concentration, amount of Pt/SiO2 and reaction conditions on the p-aminophenol yield and selectivity was investigated, and was compared with the result obtained over H2SO4 and Pt/SiO2 catalytic system.Under the reaction conditions of 85℃,4 h and 0.4 MPa, nitrobenzene conversion was 96.6% and p-aminophenol selectivity was 81.4% over Pt/SiO2 and [HSO3-b-N(CH3)3]HSO4, superior to the results over Pt/SiO2 and H2SO4.The possible reasons were the enhancement of nitrobenzene solubility influenced by ionic liquid, and the restriction of deep hydrogenation for phenylhydroxylamine.Pt/SiO2 catalyst could be recovered by filtration in vacuum, and p-aminophenol could be obtained from the filtrate by extraction, vacuum distillation and crystallization in sequence.Moreover, the ionic liquid and Pt/SiO2 catalytic system could be used for three times without obvious decrease of p-aminophenol yield.

Key words:

对氨基苯酚, 硝基苯, 酸性离子液体, Pt/SiO2