Premium
Coke Formation in a Zeolite Crystal During the Methanol‐to‐Hydrocarbons Reaction as Studied with Atom Probe Tomography
Author(s) -
Schmidt Joel E.,
Poplawsky Jonathan D.,
Mazumder Baishakhi,
Attila Özgün,
Fu Donglong,
de Winter D. A. Matthijs,
Meirer Florian,
Bare Simon R.,
Weckhuysen Bert M.
Publication year - 2016
Publication title -
angewandte chemie
Language(s) - English
Resource type - Journals
eISSN - 1521-3757
pISSN - 0044-8249
DOI - 10.1002/ange.201606099
Subject(s) - coke , zeolite , methanol , atom probe , nanoscopic scale , catalysis , nanometre , agglomerate , carbon fibers , crystal (programming language) , crystal growth , chemistry , chemical engineering , materials science , nanotechnology , crystallography , organic chemistry , composite material , computer science , programming language , transmission electron microscopy , composite number , engineering
Understanding the formation of carbon deposits in zeolites is vital to developing new, superior materials for various applications, including oil and gas conversion processes. Herein, atom probe tomography (APT) has been used to spatially resolve the 3D compositional changes at the sub‐nm length scale in a single zeolite ZSM‐5 crystal, which has been partially deactivated by the methanol‐to‐hydrocarbons reaction using 13 C‐labeled methanol. The results reveal the formation of coke in agglomerates that span length scales from tens of nanometers to atomic clusters with a median size of 30–60 13 C atoms. These clusters correlate with local increases in Brønsted acid site density, demonstrating that the formation of the first deactivating coke precursor molecules occurs in nanoscopic regions enriched in aluminum. This nanoscale correlation underscores the importance of carefully engineering materials to suppress detrimental coke formation.