Oxygen molar balance, catalytic

We shall develop next a single-channel model that captures the key features of a catalytic combustor. The catalytic materials are deposited on the walls of a monolithic structure comprising a bundle of identical parallel tubes. The combustor includes a fuel distributor providing a uniform fuel/air composition and temperature over the cross section of the combustor. Natural gas, typically >98% methane, is the fuel of choice for gas turbines. Therefore, we will neglect reactions of minor components and treat the system as a methane combustion reactor. The fuel/air mixture is lean, typically 1/25 molar, which corresponds to an adiabatic temperature rise of about 950°C and to a maximum outlet temperature of 1300°C for typical compressor discharge temperatures ( 350°C). Oxygen is present in large stoichiometric excess and thus only methane mass balances are needed to solve this problem. 

Catalytic experiments were carried out at 0.1 MPa total pressure, with molar fraction (y) of CO, CH4 or C3H8 between 0.01 and 0.04, oxygen slightly above stoichiometric value, and Ar or He as balance gas. Reaction products were monitored by on-line analysis with a gas chromatograph and a quadrupole mass spectrometer. 

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