Oxygen-and Hydrogen-Permeable Dense Ceramic Membranes

Significant research over the past 30 years has focused on dense mixed ionic-electronic conducting oxide membranes, which can selectively transport oxygen ions or protons. This chapter provides a concise review of the different structures, synthesis and experimental methods, transport properties, doping strategies to improve chemical and mechanical stability, gas permeation under different conditions, and the use of dense ceramic membranes for gas purification or in a catalyzed membrane reactor system. Gas permeation models for various cases and the effect of a reducing gas in the downstream gas on the permeation rate through membranes are emphasized. Current challenges and future directions for dense mixed conducting membrane research are briefly discussed.