Catalytic combustion of methane, methanol, and ethanol in microscale combustors with Pt/ZSM-5 packed beds

Experiments on combustion of methane, methanol, and ethanol in packed bed combustors were performed with the ZSM-5 zeolite supported nanometer-sized Pt as the catalyst. Methane combustion was investigated in the combustors in which the lengths of catalyst beds were 40, 20, and 10 mm, respectively. The stabilization and conversion rate of methane combustion were both the highest in the combustor with a 20-mm-sized catalyst bed, thus this combustor was chosen to implement the comparative studies on combustion of methanol and ethanol. Methanol showed a wider equivalence ratio (Φ) range of stable combustion, lower conversion rates, higher CO2 selectivity and higher energy release efficiencies compared to ethanol. As Φ increased from 0.8 to 1.4, the relative conversion rate of methanol increased whereas that of ethanol decreased. The mechanism of the combustion characteristics was interpreted from the aspects of fuel feature, adsorption on active sites and chemical reactions.