title: Large Ferrierite Crystals as Models for Catalyst Deactivation during Skeletal Isomerisation of Oleic Acid: Evidence for Pore Mouth Catalysis.
abstract: Large zeolite crystals of ferrierite have been used to study the deactivation, at the single particle level, of the alkyl isomerisation catalysis of oleic acid and elaidic acid by a combination of visible micro-spectroscopy and fluorescence microscopy (both polarised wide-field and confocal modes). The large crystals did show the desired activity, albeit only traces of the isomerisation product were obtained and low conversions were achieved compared to commercial ferrierite powders. This limited activity is in line with their lower external non-basal surface area, supporting the hypothesis of pore mouth catalysis. Further evidence for the latter comes from visible micro-spectroscopy, which shows that the accumulation of aromatic species is limited to the crystal edges, while fluorescence microscopy strongly suggests the presence of polyenylic carbocations. Light polarisation associated with the spatial resolution of fluorescence microscopy reveals that these carbonaceous deposits are aligned only in the larger 10-MR channels of ferrierite at all crystal edges. The reaction is hence further limited to these specific pore mouths.
authors.affiliation: Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (The Netherlands).|Croda Nederland B.V., Buurtje 1, 2800 BE Gouda (The Netherlands).
authors.forename: Sophie C C
authors.initials: SC
authors.lastname: Wiedemann
authors.affiliation: Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (The Netherlands).
authors.forename: Zoran
authors.initials: Z
authors.lastname: Ristanović
authors.affiliation: Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (The Netherlands).
authors.forename: Gareth T
authors.initials: GT
authors.lastname: Whiting
authors.affiliation: Institute of Chemical Technology, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany).
authors.forename: V R
authors.initials: VR
authors.lastname: Reddy Marthala
authors.affiliation: Department of Interface Physics, University of Leipzig, Linnéstrasse 5, 04103 Leipzig (Germany).
authors.forename: Jörg
authors.initials: J
authors.lastname: Kärger
authors.affiliation: Institute of Chemical Technology, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany).
authors.forename: Jens
authors.initials: J
authors.lastname: Weitkamp
authors.affiliation: Croda Nederland B.V., Buurtje 1, 2800 BE Gouda (The Netherlands).
authors.forename: Bas
authors.initials: B
authors.lastname: Wels
authors.affiliation: Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht (The Netherlands).
authors.forename: Pieter C A
authors.initials: PC
authors.lastname: Bruijnincx
authors.affiliation: Inorganic Chemistry and Catalysis, 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
mesh_terms: D002384:Catalysis; D007536:Isomerism; D008856:Microscopy, Fluorescence; D009055:Mouth / Q000737:chemistry*; D019301:Oleic Acid / Q000138:chemical synthesis / Q000737:chemistry*; D017641:Zeolites / Q000737:chemistry*
chemical_list: D017641:Zeolites; D019301:Oleic Acid
keywords: ferrierite; isomerisation; micro-spectroscopy; pore mouth catalysis; zeolites