Al-MCM-48分子筛对苯酚与乙酸异丙酯异丙基化反应的催化性能(英文)  

Catalytic Performance of Al-MCM-48 Molecular Sieves for Isopropylation of Phenol with Isopropyl Acetate

作　　者：Kandan VENKATACHALAM Pitchai VISUVAMITHIRAN Balachandran SUNDARAVEL Muthiapillai PALANICHAMY Velayutham MURUGESAN 

机构地区：[1]Department of Chemistry, Anna University

出　　处：《催化学报》2012年第3期478-486,共9页

基　　金：the financial support from the Department of Science and Technology (Sanction No. SR/S1/PC-10/2009, Dated 28.10.2009);University Grants Commission (UGC), New Delhi for providing funds under special assistance - DRS programme and Department of Science and Technology, New Delhi, under FIST programme for equipment facilities in the Department

摘　　要：Al-MCM-48 molecular sieves (Si/Al molar ratios = 25, 50, 75, and 100) were synthesized hydrothermally using cetyltrimethyl-ammonium bromide as the structure directing template. The orderly arrangement of mesopores was evident from the low angle X-ray diffraction patterns and transmission electron microscopy images. The catalytic performance of the materials was evaluated in the vapor phase isopropylation of phenol with isopropyl acetate. Phenol conversion decreased with the increase in the Si/Al ratio of the catalysts. The major reaction product was 4-isopropyl phenol with 78% selectivity. The delocalization of phenolic oxygen electron pair over the aromatic ring promoted para-selective alkylation. Such delocalization could be aided by the hydrophilic surface of the molecular sieves. Although an ester was used as the alkylating agent, phenyl isopropyl ether was not formed in the reaction.Al-MCM-48 molecular sieves （Si/Al molar ratios = 25, 50, 75, and 100） were synthesized hydrothermally using cetyltrimethyl-ammonium bromide as the structure directing template. The orderly arrangement of mesopores was evident from the low angle X-ray diffraction patterns and transmission electron microscopy images. The catalytic performance of the materials was evaluated in the vapor phase isopropylation of phenol with isopropyl acetate. Phenol conversion decreased with the increase in the Si/Al ratio of the catalysts. The major reaction product was 4-isopropyl phenol with 78% selectivity. The delocalization of phenolic oxygen electron pair over the aromatic ring promoted para-selective alkylation. Such delocalization could be aided by the hydrophilic surface of the molecular sieves. Although an ester was used as the alkylating agent, phenyl isopropyl ether was not formed in the reaction.

关 键 词：MCM-48分子筛 异丙基苯酚 醋酸异丙酯 催化性能 十六烷基三甲基溴化铵 透射电子显微镜 反应产物 水热法合成 

分 类 号：O643.32[理学—物理化学]