Abstract
In the present work, a detailed UV-Raman characterization of a set of protonic MFI zeolites with variable Si/Al ratio is presented. A new vibrational feature was detected: interestingly, such peak is present only when samples are carefully activated. Moreover, its intensity is quantitatively related to the Al content of the framework through a direct law. On these bases, the origin of the vibrational mode can be attributed to the Bronsted acid site. The assignment was further supported by means of exchange experiments (with deuterium, sodium and ammonium), demonstrating the relevant contribution of the Bronsted proton in this peculiar vibration. Finally, by applying a steaming-like treatment (known to be able to induce dealumination), the observed decrease in the mode intensity was related to the leaching of Al atoms out of the framework, i.e., to the destruction of a fraction of the former Bronsted sites population. In this regard, the monitoring by UV-Raman of such signal could represent an useful marke...
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.
