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Title: Oxidative dehydrogenation of propane over transition metal sulfides using sulfur as an alternative oxidant
The use of alternative oxidants for the oxidative dehydrogenation of propane (ODHP) is a promising strategy to suppress the facile overoxidation to CO x that occurs with O 2 . Gaseous disulfur (S 2 ) represents a thermodynamically “softer” oxidant that has been underexplored and yet offers a potential route to more selective propylene formation. Here we describe a system for sulfur-ODHP (SODHP). We demonstrate that various metal sulfide catalysts generate unique reaction product distributions, and that propylene selectivities as high as 86% can be achieved at 450–550 °C. For a group of 6 metal sulfide catalysts, apparent activation energies for propylene formation range from 72–134 kJ mol −1 and parallel the corresponding catalyst XPS sulfur binding energies, indicating that M–S bond strength plays a key role in SODHP activity. Kinetic data over a sulfided ZrO 2 catalyst indicate a rate law which is first-order in propane and zero-order in sulfur, suggesting that SODHP may occur via a mechanism analogous to the Mars van Krevelen cycle of traditional ODHP. The present results should motivate further studies of SODHP as a route to the selective and efficient oxidative production of propylene.  more » « less
Award ID(s):
1647722
PAR ID:
10217755
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Catalysis Science & Technology
Volume:
10
Issue:
20
ISSN:
2044-4753
Page Range / eLocation ID:
6840 to 6848
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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