醇胺法一步合成吲哚联产3-甲基吲哚工艺研究

Research on one-step synthesis of indole with co-production of 3-methylindole by alkanolamine method

制备了催化剂AKS6,以苯胺、乙二醇、丙二醇等为原料在固定床反应器中进行了气相合成吲哚联产3-甲基吲哚的单因素试验和正交试验,试验结果表明:反应温度是主要的影响因素,最优的反应条件为苯胺和乙二醇物料物质量比7∶1,苯胺和1,2-丙二醇物质的量比7∶1,反应温度320℃,空速0.4 h-1,体系压力0.7 MPa,氢气流速50 mL/min,水流速0.15 mL/min。在优化条件下进行了500 h稳定性试验研究,优化试验结果表明:该催化剂活性较好,吲哚收率稳定在75%,3-甲基吲哚收率维持在45%左右,具有较好的工业化应用前景。

The catalyst AKS6 is prepared.The single factor and orthogonal experiments of gas-phase synthesis of indole and 3-methylindole using aniline,ethylene glycol and propylene glycol as raw materials in a fixed bed are carried out.The results show the reaction temperature is the main influencing factor,and the optimizing conditions are obtained:the molar ratio of aniline to ethylene glycol is 7∶1,the molar ratio of aniline to 1,2-propanediol is 7∶1,the reaction temperature is 320℃,the space velocity is 0.4 h-1,the system pressure is 0.7 MPa,the flow rate of hydrogen is 50 mL/min,and the flow rate of water is 0.15 mL/min.Under this conditions,the stability experiment is carried out for 500 h.The results show that the catalyst has good activity,the yield of indole is stable at 75%,and the yield of 3-methylindole is maintained at about 45%,which has a good prospect of industrial application.