화학공학소재연구정보센터
Energy & Fuels, Vol.23, No.1, 86-93, 2009
Combustion of Methane in Lean Mixtures over Bulk Transition-Metal Oxides: Evaluation of the Activity and Self-Deactivation
Different bulk transition-metal oxides (NiO, CuO, Mn2O3, Cr2O3, and C0304) were prepared, by precipitation from nitrate precursors, and tested for the combustion of methane-air lean mixtures (1000-5000 ppmv of CH4). Catalyst performances were compared in terms of both intrinsic activity and resistance to self-deactivation. Methane combustion experiments were carried out at ambient pressure and a space velocity of 62 h(-1) [weight hourly space velocity (WHSV)]. The activity of the studied catalysts (determined by the recording of light-off curves in the interval of 250-600 degrees C decreases in the order: Co3O4 > Mn2O2 > Cr2O3 > CuO > NiO. However, deactivation studies, carried out both at constant temperature (620 degrees C) and in hysteresis experiments, reveal that Mn2O3 is the most stable catalyst.