对氨基苯酚的工艺研究

Study on synthesis of p-aminophenol

研究硝基苯催化加氢制备对氨基苯酚的工艺条件,对影响因素进行了探讨。结果表明,最佳制备工艺条件为:硝基苯20 mL,硫酸浓度15%,氢气压力为20 cm水柱,温度85℃,十二烷基三甲基溴化铵用量为0.1 g,搅拌速率1 500 r/m in,2.5%Pt/C催化剂0.5 g,反应时间为5 h。在此条件下,硝基苯转化率最高达39.8%,对氨基苯酚选择性最高达99%,产品质量达到日本JISK4144—1986标准要求。

The synthesis process of p-aminophenol from catalytic hydrogenation of the nitrobenzene is studied,and the factors for effecting synthesis process are discussed. The best synthesis process condition is determined. In the condition that the volume of nitrobenzene is 20 mL, the reaction temperature is 85 ℃, the concentration of sulphuric acid is 15% ,the concentration of Pt/C is 2.5% and the amount is 0.5 g, the stirring rate is 1 500 r/min,the amount of dodecyl trimethyl ammonium bromidesis 0.1 g and the reaction time is 5 h. The highest rate of conversion of nitrobenzene is 39.8% and the highest selectivity of PAP is 99%. The quality of p-aminophenol reach the standards of JISK4144--1986 in Japan.