Abstract
Temperature step infrared spectroscopy is used to monitor vibrations associated with water molecules and zeolite framework during thermal dehydration and rehydration of HY and NaY. Temperature-dependent HY and NaY infrared spectrum intensity and wavenumber trends for O-H stretching vibrations, H-O-H bending vibrations, and zeolite framework vibrations are compared. Changes in hydroxyl stretching and water bending vibration bands confirm that HY has a stronger hydrogen bonding network. The intensity of a band at 3700 cm−1 in NaY spectra varies with temperature and can be correlated with Na+ migration and zeolite water content. Spectral subtractions reveal complex intensity variations in the framework vibration band wavenumber region. Spectrum differences indicate the presence of at least four overlapping contributions in this wavenumber region. The intensities and wavenumbers of these constituents vary with temperature differently for HY and NaY. For both zeolites, infrared spectrum changes detected during thermal dehydration were mostly reversed when water re-adsorbed to the sample after cooling.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
