Modelling the partial oxidation of methane to formaldehyde on silica catalyst

Abstract

The kinetics of the partial oxidation of methane to formaldehyde (MPO) on the silica catalyst at 650°C has been investigated using a flow recirculation batch reactor. The influence of methane and oxygen concentration on density of reduced sites of the catalyst under steady-state conditions has been evaluated by in situ oxygen uptake measurements (RTOC). The reaction order with respect to CH 4 and O 2 is 0.9 and 0.2, respectively, while the density of reduced sites depends upon the square-root of the P CH 4 / P O 2 ratio. A formal Langmuir–Hinshelwood (L–H) model, accounting for the dissociative activation of both CH 4 and O 2 molecules, is adopted to describe the reaction kinetics of the MPO on silica catalyst.