Proton-conducting ceramic membrane hydrogen production

The efficiency of this cell depends on the electrode materials and their ability to produce hydrogen at low potentials, on the performance of the membrane, and on the electrolytic solution. Various relatively inexpensive electrode materials have been developed, and hydrogen production has been achieved at potentials as low as 0.5 V with ceramic carbon electrodes (Ranganathan and Easton, 2010). Additionally, several membranes have been investigated to identify those with lower copper diffusion rates but similar proton conductivities (Naterer et al., 2014 Ranganathan and Easton, 2010). Depending on these aspects and hence the current density, efficiencies ranging from 15% to 95% have been achieved (Hall et al., 2014). 

Abstract Dense ceramic membrane reactors are made from composite oxides, usually having perovskite or fluorite structure with appreciable mixed ionic (oxygen ion and/or proton) and electronic conductivity. They combine the oxygen or hydrogen separation process with the catalytic reactions into a single step at elevated temperatures (>700°C), leading to significantly improved yields, simplified production processes and reduced capital costs. This chapter mainly describes the principles of various types of dense ceramic membrane reactors, and the fabrication of the membranes and membrane reactors. 

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