title: Alkaline treatment of iron-containing MFI zeolites. Influence on mesoporosity development and iron speciation.
abstract: The effects of alkaline treatment on the mesoporosity development and iron speciation in Fe-MFI zeolites have been investigated. To this end, a variety of samples derived from different synthetic routes and having distinct Si/Al ratios and Fe content were treated in NaOH solutions and characterized by N2 adsorption, SEM, TEM, UV/vis spectroscopy, and EPR. The alkaline treatment induces a significant intracrystalline mesoporosity development by framework silicon extraction and promotes disintegration of oligomeric iron species. Iron in framework positions has shown to provoke mesopore formation, whereas nonframework iron species suppresses silicon leaching and lowers the extent of extra porosity.
authors.affiliation: DelftChemTech, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands. j.c.groen@tudelft.nl
authors.forename: Johan C
authors.initials: JC
authors.lastname: Groen
authors.forename: Lluís
authors.initials: L
authors.lastname: Maldonado
authors.forename: Elise
authors.initials: E
authors.lastname: Berrier
authors.forename: Angelika
authors.initials: A
authors.lastname: Brückner
authors.forename: Jacob A
authors.initials: JA
authors.lastname: Moulijn
authors.forename: Javier
authors.initials: J
authors.lastname: Pérez-Ramírez