title: Direct, nonoxidative conversion of methane to ethylene, aromatics, and hydrogen.
abstract: The efficient use of natural gas will require catalysts that can activate the first C-H bond of methane while suppressing complete dehydrogenation and avoiding overoxidation. We report that single iron sites embedded in a silica matrix enable direct, nonoxidative conversion of methane, exclusively to ethylene and aromatics. The reaction is initiated by catalytic generation of methyl radicals, followed by a series of gas-phase reactions. The absence of adjacent iron sites prevents catalytic C-C coupling, further oligomerization, and hence, coke deposition. At 1363 kelvin, methane conversion reached a maximum at 48.1% and ethylene selectivity peaked at 48.4%, whereas the total hydrocarbon selectivity exceeded 99%, representing an atom-economical transformation process of methane. The lattice-confined single iron sites delivered stable performance, with no deactivation observed during a 60-hour test.
authors.affiliation: State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, People's Republic of China.
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Guo
authors.forename: Guangzong
authors.initials: G
authors.lastname: Fang
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.forename: Hao
authors.initials: H
authors.lastname: Ma
authors.forename: Hongjun
authors.initials: H
authors.lastname: Fan
authors.forename: Liang
authors.initials: L
authors.lastname: Yu
authors.forename: Chao
authors.initials: C
authors.lastname: Ma
authors.forename: Xing
authors.initials: X
authors.lastname: Wu
authors.forename: Dehui
authors.initials: D
authors.lastname: Deng
authors.forename: Mingming
authors.initials: M
authors.lastname: Wei
authors.forename: Dali
authors.initials: D
authors.lastname: Tan
authors.forename: Rui
authors.initials: R
authors.lastname: Si
authors.forename: Shuo
authors.initials: S
authors.lastname: Zhang
authors.forename: Jianqi
authors.initials: J
authors.lastname: Li
authors.forename: Litao
authors.initials: L
authors.lastname: Sun
authors.forename: Zichao
authors.initials: Z
authors.lastname: Tang
authors.forename: Xiulian
authors.initials: X
authors.lastname: Pan
authors.forename: Xinhe
authors.initials: X
authors.lastname: Bao