Our research is focused on developing dense oxygen transport membranes (OTMs) that will utilize natural gas and renewable liquids to cost-effectively produce hydrogen by water splitting. In our approach, hydrogen is produced by water splitting on the steam side of the membrane while syngas, containing mainly H₂ and CO, is produced on the fuel side. The fuel establishes a large gradient in oxygen chemical potential across the OTM, which drives the removal of oxygen from the water splitting zone. The removal of oxygen shifts the water splitting equilibrium toward dissociation and enables the generation of significant amounts of hydrogen and oxygen at moderate temperatures.

As a first step in demonstrating our concept, we used OTMs to produce hydrogen via water splitting at moderate temperatures (500-900°C). A maximum hydrogen production rate of ≈17 cm³(STP)/min-cm² at 900°C was measured with a 25-μm-thick membrane. Using methane on the oxygen-permeate side of the membrane and steam on the other side, we showed that oxygen from water splitting can be used to reform carbonaceous fuels. In this process, hydrogen is produced on the steam side by water splitting and on the methane side by reaction between methane and pure oxygen transported by the OTM. Results of our experiments will be presented in this talk.

Work supported by U.S. Department of Energy (DOE), Energy Efficiency and Renewable Energy, Office of Hydrogen, Fuel Cells, and Infrastructure Technologies Program and Office of Fossil Energy, National Energy Technology Laboratory’s Hydrogen and Syngas Technology Program, under Contract DE-AC02-06CH11357.