H2S‐Mediated Thermal and Photochemical Methane Activation. Issue 17 (22nd October 2013)

• Record Type: Journal Article
• Authors: Baltrusaitis, Jonas; de Graaf, Coen; Broer, Ria; Patterson, Eric V.
• Is Part Of: Chemphyschem. Volume 14:Issue 17(2013)
• Page Start: 3960
• Page End: 3970
• Publication Date: 2013-10-22
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201300828
• Languages: English
• ISSNs: 1439-4235

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Sustainable, low‐temperature methods for natural gas activation are critical in addressing current and foreseeable energy and hydrocarbon feedstock needs. Large portions of natural gas resources are still too expensive to process due to their high content of hydrogen sulfide gas (H<sub>2</sub>S) mixed with methane, deemed altogether as sub‐quality or "sour" gas. We propose a unique method of activation to form a mixture of sulfur‐containing hydrocarbon intermediates, CH<sub>3</sub>SH and CH<sub>3</sub>SCH<sub>3</sub>, and an energy carrier such as H<sub>2</sub>. For this purpose, we investigated the H<sub>2</sub>S‐mediated methane activation to form a reactive CH<sub>3</sub>SH species by means of direct photolysis of sub‐quality natural gas. Photoexcitation of hydrogen sulfide in the CH<sub>4</sub>+H<sub>2</sub>S complex resulted in a barrierless relaxation by a conical intersection to form a ground‐state CH<sub>3</sub>SH+H<sub>2</sub> complex. The resulting CH<sub>3</sub>SH could further be coupled over acidic catalysts to form higher hydrocarbons, and the resulting H<sub>2</sub> used as a fuel. This process is very different from conventional thermal or radical‐based processes and can be driven photolytically at low temperatures, with enhanced control over the conditions currently used in industrial oxidative natural gas activation. Finally, the proposed process is CO<sub>2</sub> neutral, as opposed to the current industrial steam methane reforming (SMR).</p> </abstract>