Abstract: Methane in a feedstock gas having methane as its main component, is partially oxidized with oxygen, which selectively permeates from a first side to a second side of a oxygen selective permeation ceramic membrane. Air is contacted with the first side of the oxygen selective permeation ceramic membrane, and the feedstock gas containing methane is contacted with the second side of the oxygen selective permeation ceramic membrane. A first catalyst for partial oxidation of methane is disposed two-dimensionally on the second side of the oxygen selective permeation ceramic membrane, and a second catalyst for partial oxidation of methane is disposed three-dimensionally in the feedstock gas stream downstream from the first catalyst. Furthermore, steam is mixed into the feedstock gas stream at a ratio of 0.25 to 0.5 moles of steam based on the moles of carbon in the feedstock gas.

Abstract: Disclosed is a method for partial oxidation of methane wherein a methane partial oxidation catalyst based on Ni or on noble metal such as Ru that has low tendency of carbon precipitation, in such a quantity as deactivation of the catalyst due to oxidation does not occur, is disposed in a two-dimensional arrangement in the vicinity of the surface of the ceramic membrane where oxygen comes out thereof in the upstream of the gas flow that contains methane in the oxygen permeation membrane reactor, and the methane partial oxidation catalyst that has low tendency of carbon precipitation is disposed in a three-dimensional arrangement with respect to the ceramic membrane in the downstream of the gas flow that contains methane in the reactor, while supplying steam to the gas that contains methane and is fed to the reactor in a proportion of 0.25 to 0.5 to the carbon content in the gas.