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The 3 - Methylindole is an important nitrogen-containing heterocyclic compounds , often used as intermediates in organic synthesis has attracted increasing attention in biology, medicine and other fields . 3 - methyl- indole synthesis method have many reports , but considering the environment, cost and other factors , we choose to aniline and glycerin as the raw material step vapor phase catalytic synthesis of 3 - methylindole . This paper reports joined zinc , sodium , potassium the Promoter on Cu/SiO2-Al2O3 catalyst performance impact and depth characterization by XRD, H2-TPR, NH3-TPD and TG and other means of adding additives copper-based catalyst the relationship between the structure and performance . By inspection of the impregnation sequence , indicating that the addition of zinc , sodium , potassium aids and were used after the first ZnO Cu , Na20 and Cu , at the same time , after the first K20 Cu impregnation sequence helps to enhance the initial activity of the catalyst , the yield reached 46.9 % , 46.3% , 44.4% . Can be seen by XRD, TPR and TPD results to Cu/SiO2-Al2O3 catalyst added to the additives of the zinc , sodium or potassium , the strong interaction between the copper and the carrier , the number of weak acid catalyst , is conducive to the desired product Synthesis of 3 - methylindole . Seen by TG and XRD after the reaction , zinc , sodium or potassium additive added can not improve the stability of the catalyst . Add additives , resulting in the increased amount of catalyst coke , no significant improvement in copper particle sintering phenomenon . GC-MS test results show that N - methyl aniline , N-ethyl aniline , indole three substances as aniline and glycerol vapor phase catalytic synthesis of 3 - methylindole major byproduct .
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