TY - JOUR
T1 - Vapor phase ethanol carbonylation over Rh supported on zeolite 13X
AU - Yacob, Sara
AU - Kilos, Beata A.
AU - Barton, David G.
AU - Notestein, Justin M.
N1 - Funding Information:
The Dow Chemical Company supported this work. This XPS work was performed in the Keck-II facility of NU ANCE Center at Northwestern University. The NU ANCE Center is supported by the International Institute for Nanotechnology, MRSEC ( NSF DMR-1121262 ), the Keck Foundation , the State of Illinois , and Northwestern University . The CleanCat Core facility acknowledges funding from the Department of Energy ( DE-FG02-03ER15457 ) used for the purchase of the Altamira AMI-200. This EXAFS and in situ XANES work was performed at the DuPont-Northwestern-Dow Collaborative Access Team (DND-CAT) located at Sector 5 of the Advanced Photon Source (APS). DND-CAT is supported by Northwestern University , E.I. DuPont de Nemours & Co. , and The Dow Chemical Company . This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.
Publisher Copyright:
© 2016 Elsevier B.V. All rights reserved.
PY - 2016/6/25
Y1 - 2016/6/25
N2 - While methanol carbonylation has been extensively studied, higher alcohol carbonylation has received relatively little attention, even though, for example, ethanol carbonylation could be a useful route for the production of propionates. Here we use Rh/Na13X to investigate the vapor phase carbonylation of ethanol with an ethyl iodide co-feed. In the base case, the catalyst is ∼40% selective to propionates, with the remainder forming ethylene and diethyl ether. Deposition of additional alkali can increase selectivities to ∼60%. Isotopic labeling of ethyl iodide demonstrates reversible formation of ethyl iodide from ethanol, and that preferential incorporation of ethyl iodide initiates the Rh-catalyzed carbonylation cycle. XPS and in situ X-ray absorption spectroscopy are consistent an active anionic RhI iodide species at a zeolite exchange site. This proposed structure and the attendant catalytic reaction network are directly analogous to those of classic solution-phase Rh catalysts and other supported Rh catalysts. However, important differences are noted in the reaction orders and apparent activation barrier, which suggest that the rate of ethyl iodide formation is overall rate limiting under these conditions and for this catalyst.
AB - While methanol carbonylation has been extensively studied, higher alcohol carbonylation has received relatively little attention, even though, for example, ethanol carbonylation could be a useful route for the production of propionates. Here we use Rh/Na13X to investigate the vapor phase carbonylation of ethanol with an ethyl iodide co-feed. In the base case, the catalyst is ∼40% selective to propionates, with the remainder forming ethylene and diethyl ether. Deposition of additional alkali can increase selectivities to ∼60%. Isotopic labeling of ethyl iodide demonstrates reversible formation of ethyl iodide from ethanol, and that preferential incorporation of ethyl iodide initiates the Rh-catalyzed carbonylation cycle. XPS and in situ X-ray absorption spectroscopy are consistent an active anionic RhI iodide species at a zeolite exchange site. This proposed structure and the attendant catalytic reaction network are directly analogous to those of classic solution-phase Rh catalysts and other supported Rh catalysts. However, important differences are noted in the reaction orders and apparent activation barrier, which suggest that the rate of ethyl iodide formation is overall rate limiting under these conditions and for this catalyst.
KW - Carbonylation
KW - Ethanol
KW - Ethyl iodide
KW - Rhodium
KW - Zeolite 13X
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U2 - 10.1016/j.apcata.2016.04.006
DO - 10.1016/j.apcata.2016.04.006
M3 - Article
AN - SCOPUS:84964253124
VL - 520
SP - 122
EP - 131
JO - Applied Catalysis A: General
JF - Applied Catalysis A: General
SN - 0926-860X
ER -