Discerning the Location and Nature of Coke Deposition from Surface to Bulk of Spent Zeolite Catalysts.

ABSTRACT: The formation of carbonaceous deposits (coke) in zeolite pores during catalysis leads to temporary deactivation of catalyst, necessitating regeneration steps, affecting throughput, and resulting in partial permanent loss of catalytic efficiency. Yet, even to date, the coke molecule distribution is quite challenging to study with high spatial resolution from surface to bulk of the catalyst particles at a single particle level. To address this challenge we investigated the coke molecules in HZSM-5 catalyst after ethanol conversion treatment by a combination of C K-edge X-ray absorption spectroscopy (XAS), ¹³C Cross polarization-magic angle spinning nuclear magnetic resonance (CP-MAS NMR) spectroscopy, and atom probe tomography (APT). XAS and NMR highlighted the aromatic character

SUBMITTER: Devaraj A 

PROVIDER: S-EPMC5120296 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature