Methane coupling reaction in an oxy-steam stream through an OH radical pathway by using supported alkali metal catalysts

Handle URI:
http://hdl.handle.net/10754/563453
Title:
Methane coupling reaction in an oxy-steam stream through an OH radical pathway by using supported alkali metal catalysts
Authors:
Liang, Yin; Li, Zhikao; Nourdine, Mohamed; Shahid, Salman; Takanabe, Kazuhiro ( 0000-0001-5374-9451 )
Abstract:
A universal reaction mechanism involved in the oxidative coupling of methane (OCM) is demonstrated under oxy-steam conditions using alkali-metal-based catalysts. Rigorous kinetic measurements indicated a reaction mechanism that is consistent with OH radical formation from a H 2O-O2 reaction followed by C-H activation in CH 4 with an OH radical. Thus, the presence of water enhances both the CH4 conversion rate and the C2 selectivity. This OH radical pathway that is selective for the OCM was observed for the catalyst without Mn, which suggests clearly that Mn is not the essential component in a selective OCM catalyst. The experiments with different catalyst compositions revealed that the OH.-mediated pathway proceeded in the presence of catalysts with different alkali metals (Na, K) and different oxo anions (W, Mo). This difference in catalytic activity for OH radical generation accounts for the different OCM selectivities. As a result, a high C2 yield is achievable by using Na2WO4/SiO2, which catalyzes the OH.-mediated pathway selectively. Make it methane: A universal reaction mechanism involved in the oxidative coupling of methane is demonstrated under oxy-stream conditions by using alkali-metal-based catalysts. Rigorous kinetic measurements indicated a reaction mechanism that is consistent with OH radical formation from an H2O-O2 reaction, followed by C-H activation in CH4 with an OH radical. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
KAUST Department:
KAUST Catalysis Center (KCC); Physical Sciences and Engineering (PSE) Division; Chemical Science Program; Catalysis for Energy Conversion (CatEC)
Publisher:
Wiley-Blackwell
Journal:
ChemCatChem
Issue Date:
24-Mar-2014
DOI:
10.1002/cctc.201400018
Type:
Article
ISSN:
18673880
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division; Chemical Science Program; KAUST Catalysis Center (KCC)

Full metadata record

DC FieldValue Language
dc.contributor.authorLiang, Yinen
dc.contributor.authorLi, Zhikaoen
dc.contributor.authorNourdine, Mohameden
dc.contributor.authorShahid, Salmanen
dc.contributor.authorTakanabe, Kazuhiroen
dc.date.accessioned2015-08-03T11:51:53Zen
dc.date.available2015-08-03T11:51:53Zen
dc.date.issued2014-03-24en
dc.identifier.issn18673880en
dc.identifier.doi10.1002/cctc.201400018en
dc.identifier.urihttp://hdl.handle.net/10754/563453en
dc.description.abstractA universal reaction mechanism involved in the oxidative coupling of methane (OCM) is demonstrated under oxy-steam conditions using alkali-metal-based catalysts. Rigorous kinetic measurements indicated a reaction mechanism that is consistent with OH radical formation from a H 2O-O2 reaction followed by C-H activation in CH 4 with an OH radical. Thus, the presence of water enhances both the CH4 conversion rate and the C2 selectivity. This OH radical pathway that is selective for the OCM was observed for the catalyst without Mn, which suggests clearly that Mn is not the essential component in a selective OCM catalyst. The experiments with different catalyst compositions revealed that the OH.-mediated pathway proceeded in the presence of catalysts with different alkali metals (Na, K) and different oxo anions (W, Mo). This difference in catalytic activity for OH radical generation accounts for the different OCM selectivities. As a result, a high C2 yield is achievable by using Na2WO4/SiO2, which catalyzes the OH.-mediated pathway selectively. Make it methane: A universal reaction mechanism involved in the oxidative coupling of methane is demonstrated under oxy-stream conditions by using alkali-metal-based catalysts. Rigorous kinetic measurements indicated a reaction mechanism that is consistent with OH radical formation from an H2O-O2 reaction, followed by C-H activation in CH4 with an OH radical. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.en
dc.publisherWiley-Blackwellen
dc.subjectalkali metalsen
dc.subjectkineticsen
dc.subjectoxidative couplingen
dc.subjectradicalsen
dc.subjectreaction mechanismsen
dc.subjectsupported catalystsen
dc.titleMethane coupling reaction in an oxy-steam stream through an OH radical pathway by using supported alkali metal catalystsen
dc.typeArticleen
dc.contributor.departmentKAUST Catalysis Center (KCC)en
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.contributor.departmentChemical Science Programen
dc.contributor.departmentCatalysis for Energy Conversion (CatEC)en
dc.identifier.journalChemCatChemen
dc.contributor.institutionDepartment of Chemical Engineering, Universiti Teknologi Petronas, Tronoh, Perak, Malaysiaen
dc.contributor.institutionDepartment of Chemical Engineering, Indian Institute of Technology Kharagpur, 721302, Kharagpur West-Bengal, Indiaen
kaust.authorTakanabe, Kazuhiroen
kaust.authorLiang, Yinen
kaust.authorLi, Zhikaoen
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