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Title: Oxidative dehydrogenation of ethane over boron-containing chabazite
We report that boron -containing zeolite chabazite (B-CHA) catalyzes the oxidative dehydrogenation of ethane (ODHE) with high selectivity (>70 %) and excellent stability in the temperature range of 500-600 degrees C. ODHE rates, in fact, increase over time on stream. Ethane consumption rate has an apparent activation energy of 126 kJ mol(-1), with Langmuirian dependence on the oxygen partial pressure and first-order dependence on the ethane partial pressure. Investigation of the catalyst before and after reaction by one-dimensional B-11 magic angle spinning (1D B-11 MAS) nuclear magnetic resonance (NMR), two-dimensional B-11 multiple quantum MAS (2D B-11 MQMAS) NMR spectroscopy, and Fourier transform infrared (FTIR) spectroscopy identifies the B-OH group in defect trigonal boron (B(OSi)(OH)(2)) as the species initiating the ODHE reaction. This result could open a pathway to develop suitable catalysts for industrial ethylene production with lower greenhouse gas emissions than current non -oxidative dehydrogenation routes.  more » « less
Award ID(s):
2134471 1803246 1908982
PAR ID:
10556815
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Applied Catalysis A: General
Volume:
680
Issue:
C
ISSN:
0926-860X
Page Range / eLocation ID:
119740
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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