Authors: Pavel Čičmanec Roman Bulánek Karel Frolich
Publish Date: 2011/01/08
Volume: 105, Issue: 3, Pages: 837-844
Abstract
The existence of the new type of the adsorption complexes of carbon monoxide where CO molecule interacts simultaneously with both copper and potassium cation formed on socalled heterogeneous dual adsorption sites was detected by the FTIR spectroscopy and temperature programmed desorption technique TPD in the Cu K–FER zeolite samples The timeresolved IR spectroscopy and TPD experiments also proved their lower stability in the comparison with the classical monodentate adsorption complexes The TPD curves of these materials exhibited low temperature desorption peak which was ascribed to these sites The energetic parameters ie energy and entropy of adsorption as well as distribution of all present Cu+ sites were obtained by the fitting of TPD data to the phenomenological model Obtained results suggest that the heterogeneous dual sites are special form of the adsorption sites localized on the wall of channels destabilized due to significantly higher change of the entropy of adsorption Direct microcalorimetric measurement proved energetic equality of single and heterogeneous dual sites together with the validity of the adsorption energy values obtained from TPD
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