SELECTIVITY IN THE LIQUID-PHASE BROMINATION OF AROMATICS CATALYZED BY ZEOLITES

被引：20

作者：

DELAVEGA, F ^{[1
]}

SASSON, Y ^{[1
]}

HUDDERSMAN, K ^{[1
]}

机构：

[1] CITY LEICESTER POLYTECH,SCH APPL PHYS SCI,LEICESTER LE1 9BH,ENGLAND

来源：

ZEOLITES | 1991年 / 11卷 / 06期

关键词：

ZEOLITE; CATALYTIC; BROMINATION; SELECTIVITY; P-BROMOTOLUENE; LIQUID PHASE;

D O I：

10.1016/S0144-2449(05)80014-4

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 liquid-phase bromination of aromatics catalyzed by zeolites has been studied. We have found that two parallel processes are responsible for the low selectivities obtained, although zeolites are used as catalysts: the reactions between bromine and toluene on the outer surface of the zeolite and the cation exchange by a proton from HBr formed. The reactions on the outer surface of the zeolite and inside the zeolite show different selectivities, the reaction on the outer surface being less selective. The cation exchange lowers the catalytic activity of the zeolite. Opposite to Lewis acid catalysis, the selectivity decreases with increasing conversion in zeolite-catalyzed brominations.

引用

页码：617 / 621

页数：5

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