摘要
采用浸渍法制备Cu/SiO2-Al2O3及添加CeO2助剂的催化剂,通过H2-TPR,XRD,NH3-TPD,TG-DTA等技术对催化剂进行表征。实验结果表明,对于丙三醇与苯胺气相合成3-甲基吲哚的反应,向Cu/SiO2-Al2O3催化剂中加入适量的CeO2助剂不仅能大幅提高催化剂的选择性,还能改善其稳定性;在CeO2负载量为0.35 mmol/g的Cu-CeO2/SiO2-Al2O3催化剂上,反应运行第5 h时,3-甲基吲哚收率达到46%;CeO2助剂能提高Cu粒子在载体表面的分散度,有效抑制反应过程中Cu粒子的烧结;CeO2助剂还能增加催化剂的弱酸中心数,降低中强酸的酸性,减少催化剂表面的积碳,但不改变积碳的结构。
Cu/SiO2-Al2O3 and Cu/SiO2-A1203 modified by CeO2 were prepared by wetness inpregnation. The catalysts were characterized by means of H2-TPR, XRD, NH3-TPD and TG- DTA, and used in the vapor-phase synthesis of 3-methylindole from glycerol and aniline. The results indicated that adding an appropriate amount of CeO2 promoter into Cu/SiO2-Al2O3 could not only increase the selectivity of the catalysts remarkably but also improve their stability in the synthesis. The yield of 3-methylindole reached 46% over Cu-CeO2/SiO2-Al2O3 with CeO2 loading 0.35 mmol/g after the reaction for 5 hours. The characterizations revealed that CeO2 could promote the dispersion of Cu particles on the support surface and efficiently inhibited the sintering of the copper particles during the reaction. Furthermore, the CeO2 promoter could increase the weak acid sites on the catalysts, weaken the acidity of the moderate-strong acid sites and inhibit the coke formation. The addition of CeO2 did not change the texture of the coke.
出处
《石油化工》
CAS
CSCD
北大核心
2014年第2期181-185,共5页
Petrochemical Technology
基金
国家自然科学基金项目(21173110)
