title: Visualizing Dealumination of a Single Zeolite Domain in a Real-Life Catalytic Cracking Particle.
abstract: Fluid catalytic cracking (FCC) catalysts play a central role in the chemical conversion of crude oil fractions. Using scanning transmission X-ray microscopy (STXM) we investigate the chemistry of one fresh and two industrially deactivated (ECAT) FCC catalysts at the single zeolite domain level. Spectro-microscopic data at the Fe L3 , La M5 , and Al K X-ray absorption edges reveal differing levels of deposited Fe on the ECAT catalysts corresponding with an overall loss in tetrahedral Al within the zeolite domains. Using La as a localization marker, we have developed a novel methodology to map the changing Al distribution of single zeolite domains within real-life FCC catalysts. It was found that significant changes in the zeolite domain size distributions as well as the loss of Al from the zeolite framework occur. Furthermore, inter- and intraparticle heterogeneities in the dealumination process were observed, revealing the complex interplay between metal-mediated pore accessibility loss and zeolite dealumination.
authors.affiliation: Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands.
authors.forename: Sam
authors.initials: S
authors.lastname: Kalirai
authors.affiliation: Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands.
authors.forename: Pasi P
authors.initials: PP
authors.lastname: Paalanen
authors.affiliation: Canadian Light Source Inc., University of Saskatchewan, 44 Innovation Blvd., Saskatoon, SK, S7N 2V3, Canada.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.affiliation: Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands.
authors.forename: Florian
authors.initials: F
authors.lastname: Meirer
authors.affiliation: Inorganic Chemistry and Catalysis group, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands. b.m.weckhuysen@uu.nl.
authors.forename: Bert M
authors.initials: BM
authors.lastname: Weckhuysen
keywords: X-ray microscopy; dealumination; fluid catalytic cracking; heterogeneous catalysis; zeolites