Mesoporous Co3O4 catalysts for VOC elimination: Oxidation of 2-propanol

• Published in: Applied catalysis. A, General Vol. 590; no. C; p. 117366
• Main Authors: Dissanayake, Shanka, Wasalathanthri, Niluka, Shirazi Amin, Alireza, He, Junkai, Poges, Shannon, Rathnayake, Dinithi, Suib, Steven L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 25-01-2020; Elsevier Science SA; Elsevier
• Subjects: 2-propanol; Carbon dioxide; Carbonyls; Catalysis; Catalysts; Cobalt oxides; Low temperature; Mesoporous Co3O4; Micelles; Oxidation; Substrates; VOCs oxidation; VOCs oxidation; Mesoporous Co3O4; 2-propanol; Catalysis
• ISSN: 0926-860X; 1873-3875
• DOI: 10.1016/j.apcata.2019.117366

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•Mesoporous Co3O4 showed high activity for elimination of 2-propanol at low temperature.•Better low temperature reducibility, large pore volumes, higher Co3+/ Co2+ amounts, and higher number of surface-active oxygen species are crucial for higher activity.•Reaction involves formation of carbonyl and carbonate species on the surface of the catalyst before complete oxidation to CO2 and H2O.•Long term durability and maintaining activity in the presence of water and carbon dioxide make these catalysts attractive.•The developed catalytic protocol sheds light on non-precious metal catalysts for VOC elimination.
Mesoporous cobalt oxides were prepared by an inverse micelle method and calcined at different temperatures. These materials exhibited superior activity for oxidation of 2-propanol as the model substrate for VOC elimination. Highest active Co3O4-350 material showed a maximum turnover frequency of 25.8 h−1 at 160 °C at a weight hourly space velocity of 60 L g-1 h−1. The apparent activation energies of mesoporous cobalt oxides ranged from 69.7 kJ/mol to 115.6 kJ/mol. In situ Diffuse Reflectance Infrared spectroscopy (DRIFTS) revealed that the reaction involves formation of carbonyl and carbonate species on the surface of the catalyst before complete oxidation to CO2 and H2O. The activities of the materials were correlated to better low temperature reducibility, large pore volumes, higher Co3+/ Co2+ ratios, and higher number of surface-active oxygen species.