Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Analytical Chemistry

Catalyst Active Site Revealed

An Al–O–Mo linkage is the active species in a molybdenum-based zeolite catalyst that converts methane to benzene

by Mitch Jacoby
March 11, 2008

By coupling materials synthesis and catalytic-activity studies with a powerful NMR spectroscopy method, a team of researchers at Pacific Northwest National Laboratory, in Richland, Wash., and the Dalian Institute of Chemical Physics in China has identified the active species in a molybdenum-based zeolite (aluminosilicate) catalyst that converts methane to benzene. It is an aluminum-oxygen-molybdenum linkage (J. Am. Chem. Soc., DOI: 10.1021/ja7110916). The study could lead to efficient methods for transforming methane into more valuable and easily transported liquids, which in turn could provide the chemical industry with incentives to tap supplies of natural gas in remote areas.

To boost ordinarily weak Mo NMR signals, Heng Zheng, Xinhe Bao, and coworkers prepared a series of catalysts from a 95Mo-enriched precursor material, evaluated the materials' catalytic activities, and used an ultra high-field NMR method to probe the samples. On the basis of those measurements, the team concluded that during catalyst preparation molybdenum atoms migrate into the zeolite channels and anchor onto acidic aluminum sites, thereby forming Al???O???Mo linkages. These structures serve as catalytically active centers in the methane-conversion reactions.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.