Zagazig University Digital Repository
Home
Thesis & Publications
All Contents
Publications
Thesis
Graduation Projects
Research Area
Research Area Reports
Search by Research Area
Universities Thesis
ACADEMIC Links
ACADEMIC RESEARCH
Zagazig University Authors
Africa Research Statistics
Google Scholar
Research Gate
Researcher ID
CrossRef
Effect of Li-2-doping on surface and catalytic properties of Co3O4-MoO3/Al2O3 system
Faculty
Science
Year:
2003
Type of Publication:
Article
Pages:
235-245
Authors:
Ghozza, AM, El-Shobaky, GA, Mohamed, GM
DOI:
10.1016/S0926-860X(02)00468-4
Journal:
APPLIED CATALYSIS A-GENERAL ELSEVIER SCIENCE BV
Volume:
241
Research Area:
Chemistry; Environmental Sciences \& Ecology
ISSN
ISI:000181260400019
Keywords :
Li2O-doping, oxidation of CO by O-2, CoAl2O4, CoMoO4
Abstract:
The effect of Li2O-doping on solid-solid interaction, surface and catalytic properties Of Co3O4-MoO3/Al2O3 system were investigated using XRD, XPS, nitrogen adsorption at -196degreesC and oxidation of CO by O-2 at 100-300degreesC. The nominal composition of the system was 0.2 Co3O4-0.05 MoO3/Al2O3 and the amount of dopant was varied between 0.14 and 0.57 wt.\% Li2O. The results revealed that Li2O-doping inhibited the formation of CoAl2O4 and CoMoO4 in the treated solids precalcined at 800degreesC and decreased the degree of crystallinity Of Co3O4. Also, Li2O-doping of the investigated system decreased the surface concentration of cobalt species and increased that of molybdenum species. The specific surface areas of the doped adsorbents precalcined at 600, 800 and 1000degreesC decreased progressively as a function of the amount of dopant added. The catalytic activities of pure and doped solids, in CO oxidation by O-2, decreased progressively by increasing the precalcination temperature in the range 600-1000degreesC. The doping process brought about a significant increase in the catalytic activities of the solids investigated due to an effective hindrance of formation of CoAl2O4 and CoMoO4 which exhibit catalytic activities smaller than that Of Co3O4. Lithia-doping of the investigated system did not modify the mechanism of the catalytic reaction but changed the concentration of catalytically active constituents without changing their energetic nature. (C) 2002 Elsevier Science B.V. All rights reserved.
Online
PDF
جامعة المنصورة
جامعة الاسكندرية
جامعة القاهرة
جامعة سوهاج
جامعة الفيوم
جامعة بنها
جامعة دمياط
جامعة بورسعيد
جامعة حلوان
جامعة السويس
شراقوة
جامعة المنيا
جامعة دمنهور
جامعة المنوفية
جامعة أسوان
جامعة جنوب الوادى
جامعة قناة السويس
جامعة عين شمس
جامعة أسيوط
جامعة كفر الشيخ
جامعة السادات
جامعة طنطا
جامعة بنى سويف