Modelling the partial oxidation of methane to formaldehyde on silica catalyst

The kinetics of the partial oxidation of methane to formaldehyde (MPO) on t he silica catalyst at 650 degrees C has been investigated using a flow reci rculation batch reactor. The influence of methane and oxygen concentration on density of reduced sites of the catalyst under steady-state conditions h as been evaluated by in situ oxygen uptake measurements (RTOC). The reactio n order with respect to CH4 and O-2 is 0.9 and 0.2, respectively, while the density of reduced sites depends upon the square-root of the PCH4/PO2 rati o. A formal Langmuir-Hinshelwood (L-H) model, accounting for the dissociati ve activation of both CH4 and O-2 molecules, is adopted to describe the rea ction kinetics of the MPO on silica catalyst. (C) 2000 Elsevier Science B.V . All rights reserved.