Campus Units
Chemistry, Ames Laboratory
Document Type
Article
Publication Version
Published Version
Publication Date
9-2015
Journal or Book Title
ACS Catalysis
Volume
5
Issue
11
First Page
6426
Last Page
6435
DOI
10.1021/acscatal.5b01519
Abstract
Catalytic performance and the nature of surface adsorbates were investigated for high-surface-area ceria during the ethylbenzene oxidative dehydrogenation (ODH) reaction using CO2 as a soft oxidant. The high surface area ceria material was synthesized using a template-assisted method. The interactions among ethylbenzene, styrene, and CO2 on the surface of ceria and the role of CO2 for the ethylbenzene ODH reaction have been investigated in detail by using activity test, in situ diffuse reflectance infrared and Raman spectroscopy. CO2 as an oxidant not only favored the higher yield of styrene but also inhibited the deposition of coke during the ethylbenzene ODH reaction. Ethylbenzene ODH reaction over ceria followed a two-step pathway: ethylbenzene is first dehydrogenated to styrene with H2 formed simultaneously, and then CO2 reacts with H2 via the reverse water gas shift. The produced styrene can easily undergo polymerization to form polystyrene, which is a key intermediate for coke formation. In the absence of CO2, the produced polystyrene transforms into graphite-like coke at temperatures above 500 °C, which leads to catalyst deactivation. In the presence of CO2, the coke deposition can be effectively removed via oxidation with CO2.
Copyright Owner
American Chemical Society
Copyright Date
2015
Language
en
File Format
application/pdf
Recommended Citation
Zhang, Li; Nelson, Nicholas C.; Sadow, Aaron D.; Slowing, Igor I.; and Overbury, Steven H., "Role Of CO2 As a Soft Oxidant For Dehydrogenation of Ethylbenzene to Styrene over a High-Surface-Area Ceria Catalyst" (2015). Ames Laboratory Publications. 297.
https://lib.dr.iastate.edu/ameslab_pubs/297
Comments
Reprinted (adapted) with permission from ACS Catalysis 5 (2015): 6426, doi:10.1021/acscatal.5b01519. Copyright 2015 American Chemical Society.