Dual-layer hollow fiber membranes and methods of making and use

An asymmetric hollow fiber membrane for oxidative coupling of methane, comprising:

• an inner bore having an inner diameter;
• an inner porous layer surrounding the inner bore, the inner porous layer having an interconnected network of pores defined therein;
• and
• an outer separation layer surrounding the inner porous layer, the outer separation layer being substantially non-porous, wherein
• the inner porous layer comprises an oxidative coupling of methane (OCM) catalyst and the outer separation layer comprises a membrane for oxygen separation and transport through the outer separation layer,
• the inner porous layer has a thickness as measured from an outer circumferential edge of the inner bore to an interface between the inner porous layer and the outer separation layer,
• the outer separation layer has a thickness as measured from the interface to an outer circumferential edge of the hollow fiber membrane,
• the thickness of the inner porous layer is greater than the thickness of the outer separation layer,
• the outer separation layer has a thickness of about 5 μm to 100 μm,
• and the thickness of the inner porous layer, the thickness of the outer separation layer, and a porosity of the inner porous layer are each selected such that a rate of transport of oxygen through the outer separation layer equals a rate of methane activation at the inner porous layer when a methane containing source is flowed through the inner porous layer and an oxygen source is flowed through the outer separation layer at a temperature of about 700° C. to 900° C.