DESORPTION-DIFFUSION OF AMMONIA IN MOLECULAR-SIEVES .4. DECATIONATED ZSM5 ZEOLITE

被引：12

作者：

FORNI, L

VATTI, FP

ORTOLEVA, E

机构：

[1] Dipartimento di Chimica Fisica ed Elettrochimica, Universitá di Milano, Milano

来源：

ZEOLITES | 1992年 / 12卷 / 01期

关键词：

TEMPERATURE-PROGRAMMED DESORPTION OF AMMONIA FROM ZSM5;

D O I：

10.1016/0144-2449(92)90018-K

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 analysis of t.p.d.a. spectra from ZSM5 is reported, assuming various chemical or physical steps as rate-determing. After saturation, quite long isothermal desorption times (up to 50 h) were needed, before starting the temperature ramp, to obtain reproducible data. Intracrystalline diffusion was found to be the probable rate-determining step with apparent activation energy of ca. 13 kcal/mol. A comparison of the present results with the ones obtained with HNaY zeolites provided information on the most probable hindering phenomena characterizing the overall diffusive process.

引用

页码：101 / 106

页数：6

共 20 条

[1] APPLICATION OF FLASH-DESORPTION METHOD TO CATALYST STUDIES .1. ETHYLENE-ALUMINA SYSTEM [J].