Abstract
The surface active Fe-sites in HZSM-5 with low content of iron (<1000ppm) activated by steaming and high temperature (up to 1323K) calcination in inert lead to the formation of surface oxygen (O)ad species from N2O and were characterized quantitatively by transient response method. Only a part of (O)ad deposited on zeolite by decomposing N2O was active in CO oxidation at 523K. A binuclear Fe-center is suggested as an active center, featuring a “diamond core” structure, similar to that of the monooxygenase enzyme. The active O-atoms were assigned to the paired terminal oxygen atoms each bound to one Fe-site in the binuclear [Fe2O2H]+-cluster.Zeolite pre-saturated by water vapor at 473–523K generates (O)ad species from N2O completely inactive in the CO oxidation. The total amount of the oxygen, (O)ad, deposited on the pre-saturated by water zeolite corresponds to a half of stoichiometric amount of the surface Fe-atoms and suggests that water blocks a half of the binuclear [Fe2O2H]+-center, the remaining acting as a single Fe-site.
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.
