Chapter 18: Engineering Aspects of MIEC Hollow Fiber Membranes for Oxygen Production

Mixed ionic-electronic conducting (MIEC) hollow fibre membranes have attracted considerable interests in the last decade due to their advantages over other configurations in oxygen production such as high surface area/volume ratio, facile high-temperature sealing and reduced resistance to oxygen permeation. In order to meet the practical application requirements, i.e., sufficient oxygen permeability, sustainable mechanical integrity and high structural/chemical stability, the macro- and micro-structures of the MIEC hollow fibre membranes have to be tailored by carefully controlling the spinning and sintering conditions or by the post surface modifications. In oxygen production, the vacuum operation is one of the suitable modes for itshigh energy-efficiency and low requirements for the system materials. The membrane area and the operating temperature should be optimized so that the oxygen recovery is limited within 20 − 40%. In order to commercialize the MIEC hollow fibre membranes for oxygen production, some challenges have to be faced especially including the decrease of membrane costs, the assembly of hollow fibres into modules and the high-temperature sealing in the system fabrication.