Name
Core-shell structure Mg6MnO8@Li/Na binary tungstates as redox catalysts for enhanced chemical looping oxidative dehydrogenation of ethane
Description

In this study, Mg6MnO8 modified with Li2WO4 and/or Na2WO4 were synthesized and used as oxygen carriers for the chemical looping oxidative dehydrogenation (CL-ODH) of ethane. The Mg6MnO8-LiNaW2 sample demonstrates observable performance, surpassing that of most previously reported promoter-modified composite metal oxides, achieving 77.7% ethane conversion, 86.5% ethylene selectivity, and 67.2% H2 conversion. TG analysis indicates that the Mg6MnO8-LiNaW2 effective lattice oxygen capacity is up to 3.5% and has excellent reactivity above 725°C. Morphology characterization unveils that Mg6MnO8-LiNaW2 has a core-shell structure with a loose and porous surface, which could alleviate agglomeration effectively during the cyclic process. XPS results reveal that the co-doping of Li-Na-W facilitate the diminution of surface OH-/CO32- and Mn4+ species, favoring the stabilization of the surface species during the cyclic process and enabling stable reaction performance in 20 redox experiments. DFT calculations indicate that the co-doping of Li-Na-W on the surface of Mg6MnO8 effectively decreases the electron loss from the oxygen carrier surface and promotes the formation of oxygen vacancy.

Location Name
Max Bell 251
Full Address
Banff Centre for Arts and Creativity
107 Tunnel Mountain Dr
Banff AB T1L 1H5
Canada
Session Type
Poster
Abstract ID
1115