سال انتشار: ۱۳۸۷

محل انتشار: همایش بین المللی ژئولیت ایران

تعداد صفحات: ۶

نویسنده(ها):

a Teimouri – Chemical Engineering Department, Amirkabir University of Technology
a Najafi Chermahini – Department of Chemistry, Yasuj University, Yasuj
h.a Dabbagh – Department of Chemistry, Isfahan University of Technology, Isfahan

چکیده:

The formation of diazotizing reagent starts with protonation of nitrous acid under strongly acidic
conditions, and azo coupling carried out at low temperature in the presence of nucleophilic coupling
components [1]. These conventional acid–base catalyzed processes are effective for the near quantitative
formation of the desired products. But the main limitation of such synthetic processes is their environmental
incompatibility. The acidic and basic effluents from the laboratory and industry produce permanent damage
to the environment and disturb the ecological balance [2]. Clays have long been used as acidic catalysts and
existence of both Lewis and Bronsted acid sites [3]. Montmorillonite clay, enable to function as an effcient
solid acid catalyst in organic transformations with excellent product, regio- and stereo-selectivity [4].
Nowadays more and more heterogeneous Bronsted acids, e.g. zeolites are utilized, the excellent catalytic
abilities are due to the presence of Bronsted and Lewis acid centers in the zeolite structure [5]. Because of its
high protonic acidity and unique shape-selective behavior,