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Fluctuating Storage of the Active Phase in a Mn-Na2 WO4 /SiO2 Catalyst for the Oxidative Coupling of Methane.

ABSTRACT: Structural dynamics of a Mn-Na2 WO4 /SiO2 catalyst were detected directly under reaction conditions during the oxidative coupling of methane via in situ XRD and operando Raman spectroscopy. A new concept of fluctuating storage and release of an active phase in heterogeneous catalysis is proposed that involves the transient generation of active sodium oxide species via a reversible reaction of Na2 WO4 with Mn7 SiO12 . The process is enabled by phase transitions and melting at the high reaction temperatures that are typically applied.

SUBMITTER: Werny MJ

PROVIDER: S-EPMC7496389 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Fluctuating Storage of the Active Phase in a Mn-Na2 WO4 /SiO2 Catalyst for the Oxidative Coupling of Methane.

Werny Maximilian J MJ Wang Yuanqing Y Girgsdies Frank F Schlögl Robert R Trunschke Annette A

Angewandte Chemie (International ed. in English) 20200617 35

Structural dynamics of a Mn-Na2 WO4 /SiO2 catalyst were detected directly under reaction conditions during the oxidative coupling of methane via in situ XRD and operando Raman spectroscopy. A new concept of fluctuating storage and release of an active phase in heterogeneous catalysis is proposed that involves the transient generation of active sodium oxide species via a reversible reaction of Na2 WO4 with Mn7 SiO12 . Th ...[more]

PMID: 32364281

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