Composite, High-Temperature Seals for Gas Separation Membrane Devices

76066S Ceramic membranes with ion-specific conducting properties can provide gases with purity unmatched by other gas separation methods. However, in order to realize the full potential of these membrane devices, high temperature seal materials are required to isolate the ultrahigh purity product gas from the inlet gas mixture. This project will develop a composite seal material that combines the thermal and physical characteristics of a rigid crystalline phase with the wetting and process compatibility of a vitreous phase. In Phase I, the composite seal was used to demonstrate a leak-tight joint between metal and ceramic couples. Thermal cycle capability was also demonstrated. In Phase II, additional compositions will be evaluated to obtain seal materials with a range of physical and thermal properties. The sealing efficiency will be demonstrated in a short stack assembly of prototype membrane devices. Commercial Applications and Other Benefits as described by the awardee: The new seal material should be applicable to various types of high temperature membrane devices for use in ultrahigh purity oxygen and hydrogen separations, steam electrolyzers, chemical synthesis reactors, and solid oxide fuel cells.