Collect. Czech. Chem. Commun. 1980, 45, 9-16

Behaviour of CoNaA zeolites in interaction with water

Blanka Wichterlová, Ludmila Kubelková and Pavel Jírů

J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, 121 38 Prague 2


The influence of dehydration and adsorption of water on the coordination of cations, the state of adsorbed water, and stretching vibrations of CoNaA and NaA zeolites was investigated by means of electronic and infrared spectroscopy. Complexes of Co2+ change their symmetry from octahedral through tetrahedral to planar trigonal. The role of ligands play both skeletal oxygens and molecular water. The formation of OH groups either on skeleton or on Co2+ ions was not found; the existence of these groups was assumed in the literature to explain the catalytic activity of CoNaA zeolites in the isomerization of butenes.