A method for partially oxidizing methane by providing a reactor, said method comprising: providing a first chamber having an entrance inlet in which said first chamber comprises a channel with a length longer than 600mm forming a passageway for a first reactant gas in the form of methane; providing a second chamber forming a passageway for a second reactant gas in the form of oxygen; the first reactant gas in the form of methane is prevented from mixing with the second reactant gas in the form of oxygen by a metal sealing cylinder that surrounds the end of the porous catalytic membrane; providing a porous catalytic membrane separating the first and second chambers, said membrane being capable of allowing the second reactant gas to permeate from the second chamber through to the first chamber to react with the first reactant gas in a reaction zone of the apparatus wherein the oxygen and methane gas (212, 211) contact in the porous catalytic membrane with the bulk flow of gas from the centre of the porous catalytic membrane to the reaction chamber; the first reactant gas in the form of methane is fed into a nozzle entering the distribution chamber; the first reactant gas is at a temperature below 600°C with the distribution chamber being protected by the refractory material; the first reactant gas then passes through the plate and the refractory material in the distribution chamber and then through an orifice in the first chamber; wherein the first reactant gas in the form of oxygen is fed via a manifold into each individual catalytic membrane through a sealing cap which allows insertion of the porous catalytic membrane into the reactor and also forms a pressure seal against the plate; said partial oxidation for methane by said oxygen occurring wherein a turbulence inducing device is included in the methane stream at the entrance to the first chamber, wherein the turbulence device is a swirl device which imparts turbulence in the form of both rotational and linear velocity to the methane gas stream, with the following gas having a Reynolds number greater than 4,000 which is fed into a chamber bounded by a sheath and catalytic membrane wherein there is a gap between the sheath and catalytic membrane which is adapted to allow turbulent flow to develop; said reaction being adiabatic; said porous catalytic membrane is substantially cylindrical and is rhodium based; and producing syngas in ratios of 1.8:1 H 2 /CO to 6:1; and wherein the syngas produced remains outside the porous catalytic membrane and exits the shell of the reactor. providing a first chamber having an entrance inlet in which said first chamber comprises a channel with a length longer than 600mm forming a passageway for a first reactant gas in the form of methane; providing a second chamber forming a passageway for a second reactant gas in the form of oxygen; the first reactant gas in the form of methane is prevented from mixing with the second reactant gas in the form of oxygen by a metal sealing cylinder that surrounds the end of the porous catalytic membrane; providing a porous catalytic membrane separating the first and second chambers, said membrane being capable of allowing the second reactant gas to permeate from the second chamber through to the first chamber to react with the first reactant gas in a reaction zone of the apparatus wherein the oxygen and methane gas (212, 211) contact in the porous catalytic membrane with the bulk flow of gas from the centre of the porous catalytic membrane to the reaction chamber; the first reactant gas in the form of methane is fed into a nozzle entering the distribution chamber; the first reactant gas is at a temperature below 600°C with the distribution chamber being protected by the refractory material; the first reactant gas then passes through the plate and the refractory material in the distribution chamber and then through an orifice in the first chamber; wherein the first reactant gas in the form of oxygen is fed via a manifold into each individual catalytic membrane through a sealing cap which allows insertion of the porous catalytic membrane into the reactor and also forms a pressure seal against the plate; said partial oxidation for methane by said oxygen occurring wherein a turbulence inducing device is included in the methane stream at the entrance to the first chamber, wherein the turbulence device is a swirl device which imparts turbulence in the form of both rotational and linear velocity to the methane gas stream, with the following gas having a Reynolds number greater than 4,000 which is fed into a chamber bounded by a sheath and catalytic membrane wherein there is a gap between the sheath and catalytic membrane which is adapted to allow turbulent flow to develop; said reaction being adiabatic; said porous catalytic membrane is substantially cylindrical and is rhodium based; and producing syngas in ratios of 1.8:1 H 2 /CO to 6:1; and wherein the syngas produced remains outside the porous catalytic membrane and exits the shell of the reactor.