Influence of Preparation Conditions of Mixed-valence Con+/ZSM-5 Zeolites on Their Adsorption and Catalytic Properties in CO Oxidation

• Published in: Adsorption science & technology Vol. 20; no. 4; pp. 371 - 379
• Main Authors: Oleksenko, Ludmila P., Yatsimirsky, Vitaly K., Lutsenko, Larisa V.
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.05.2002; Multi Science
• Subjects: Catalysis; Catalytic reactions; Chemistry; Exact sciences and technology; General and physical chemistry; Solid-liquid interface; Surface physical chemistry; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Liquid solid interface; Catalytic reaction; Liquid solid adsorption; Cobalt ion; Zeolite; Experimental study; Thermal stability; Molecular sieve; Heterogeneous catalysis; Oxidation; Carbon monoxide; Ion exchange; Mixed valence; Catalyst activity; Modified material
• ISSN: 0263-6174; 2048-4038
• DOI: 10.1260/02636170260295551

The adsorption properties, thermal stability and catalytic activity in CO oxidation of Co2+, Co3+-containing ZSM-5 zeolite systems with different metal loadings were studied. Treatment in H2 caused an increase in the activity of Co2+/ZSM-5 and Co2+–Co3+/ZSM-5 systems, but the activity of the Co3+/ZSM-5 system remained unchanged, demonstrating the very low reducibility of the [Co(NH3)6]3+ ion when embedded in the zeolite framework. The catalytic activity changed in the order: Co3+/ZSM-5 < Co2+–Co3+/ZSM-5 < Co2+/ZSM-5. A correlation was established between the temperature necessary for the total decomposition of the cobalt salts introduced into the zeolite, the acidity, the coordination state of the Co ions and the catalytic activity of the cobalt-containing zeolites.