Aromatization mechanism of coupling reaction of light alkanes with CO over acidic zeolites: Cyclopentenones as key intermediates

被引：27

作者：

Wei, Changcheng ^{[1
,2
]}

Li, Jinzhe ^{[1
]}

Yang, Kuo ^{[1
]}

Yu, Qijun ^{[1
]}

Zeng, Shu ^{[1
,2
]}

Liu, Zhongmin ^{[1
,2
]}

机构：

[1] Chinese Acad Sci, Dalian Inst Chem Phys, Natl Engn Lab Methanol Olefins, Dalian Natl Lab Clean Energy, Dalian 116023, Peoples R China

[2] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

来源：

CHEM CATALYSIS | 2021年 / 1卷 / 06期

基金：

中国国家自然科学基金;

关键词：

FRIEDEL-CRAFTS ACYLATION; CARBON-MONOXIDE; CARBENIUM IONS; CATALYTIC-ACTIVITY; SULFATED ZIRCONIA; CARBOXYLIC-ACIDS; NMR OBSERVATION; N-HEXANE; H-BETA; CARBONYLATION;

D O I：

10.1016/j.checat.2021.09.004

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The aromatization of light alkanes (C-4-C-6) is an important value-added reaction. However, the yield of aromatics is always limited by the simultaneous generation of small alkanes (CH4 and C2H6) due to H/C balance. Herein, we demonstrate that the introduction of CO into light alkanes over zeolites significantly enhanced aromatic selectivity and an aromatics selectivity of 85% was achieved in the case of cyclopentane and CO coupling reaction over H-ZSM-5. Methyl-substituted cyclopentenones were observed and considered as the most important intermediates for aromatics formation. Multiple characterizations revealed the coupling mechanism: (1) CO inserts into carbenium ions to form acylium cations, (2) acylium cations react with olefins to generate unsaturated ketones, (3) unsaturated ketones cyclize to methylsubstituted cyclopentenones, (4) methyl-substituted cyclopentenones convert to monocytic aromatics. Methyl-substituted indanones were also discovered causing the generation of binuclear aromatics, such as naphthalene. Nano-sized ZSM-5 and TEOS modifications were applied to enhance the BTX selectivity.

引用

页码：1273 / 1290

页数：18

共 65 条

[1] Catalytic dehydroaromatization of n-alkanes by pincer-ligated iridium complexes [J].