skip to main content

DOE PAGESDOE PAGES

Title: Theoretical insights into the selective oxidation of methane to methanol in copper-exchanged mordenite

Selective oxidation of methane to methanol is one of the most difficult chemical processes to perform. A potential group of catalysts to achieve CH 4 partial oxidation are Cu-exchanged zeolites mimicking the active structure of the enzyme methane monooxygenase. However, the details of this conversion, including the structure of the active site, are still under debate. In this contribution, periodic density functional theory (DFT) methods were employed to explore the molecular features of the selective oxidation of methane to methanol catalyzed by Cu-exchanged mordenite (Cu-MOR). We focused on two types of previously suggested active species, CuOCu and CuOOCu. Our calculations indicate that the formation of CuOCu is more feasible than that of CuOOCu. In addition, a much lower C–H dissociation barrier is located on the former active site, indicating that C–H bond activation is easily achieved with CuOCu. We calculated the energy barriers of all elementary steps for the entire process, including catalyst activation, CH 4 activation, and CH 3OH desorption. Finally, our calculations are in agreement with experimental observations and present the first theoretical study examining the entire process of selective oxidation of methane to methanol.
Authors:
 [1] ;  [2] ;  [3] ;  [2] ;  [2]
  1. SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States); Tianjin Univ., Tianjin (People's Republic of China)
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States)
  3. SLAC National Accelerator Lab., Menlo Park, CA (United States); Stanford Univ., Stanford, CA (United States); Univ. Autonoma de Barcelona, Barcelona (Spain)
Publication Date:
Grant/Contract Number:
AC02-76SF00515
Type:
Accepted Manuscript
Journal Name:
ACS Catalysis
Additional Journal Information:
Journal Volume: 6; Journal Issue: 6; Journal ID: ISSN 2155-5435
Publisher:
American Chemical Society (ACS)
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; copper; density functional theory; methane activation; methanol; mordenite; zeolite
OSTI Identifier:
1349409