? Nonthermal Plasma-enhanced Catalytic Methanation of CO over Ru/TiO2/Al2O3

Abstract

Catalytic methanation of carbon monoxide (CO) was investigated in a nonthermal plasma (NTP) reactor packed with Ru/TiO2/Al2O3 catalyst pellets. With the NTP alone, no conversion of CO was observed over the entire temperature range of 240 300 ◦C, but the combination of plasma and catalyst was found to greatly improve the catalytic conversion of CO, particularly in the lower temperature region below 280 ◦C. Higher CO conversion efficiencies were obtained at higher applied voltages because of increased NTP action in the catalytic reactions. The increase in the voltage resulted in a decrease in the activation energy for methanation. Reaction products, including CH4 and CO2, were identified by using a Fourier transform infrared (FTIR) spectrometer. The increases in the applied voltage and in the temperature tended to slightly bring down the selectivity toward CH4, it being more than 0.93 under all experimental conditions explored.