Characterizing Permeation of Hydrogen Across Palladium-Silver Membranes

The increased interest in commercial fusion for energy generation has coincided with a renewed interest in palladium-silver permeators to separate hydrogen isotopes from inert carrier gas streams. To meet this need, Tritium Solutions, Inc. and Torion Plasma Corporation have collaborated to design, manufacture, and characterize high-throughput tritium-compatible flow-through permeators for commercial use. In this work, we present models to describe and predict the performance of these devices, as well as best practices to achieve optimal performance. These principles are applied to the spaghetti-tube permeator, a prototype unit named for its geometry produced by Torion Plasma Corporation. The throughput-pressure relationship and permeability are measured in the context of dead-ended permeation of pure hydrogen. The permeation of hydrogen-helium mixtures in flow-through configurations is performed, and the reduction in the permeation rates with increasing helium content is demonstrated.