Testing of polymer membranes for the selective permeability of hydrogen

Selective gas barriers are of prime importance in thin polymer membranes. The focus of this work was to find a polymer membrane that allows the transport of H₂ and acts as a barrier to CO₂ and chlorinated organics. Membrane screening has included the following testing: single gas permeability measurements, mixed gas separations, and polymer physical characterization. Single gas permeability measurements were made using the time-lag method for five gases (H₂, O₂, N₂, CO₂, and CH₄). Permeability coefficients and selectivities for the gas pair H₂/CO₂ are presented. Mixed gas separations were performed to measure actual separation factors for H₂/CCl₄ and to determine the effects on hydrogen permeability caused by exposing polymers to chlorinated hydrocarbons. The results of basic polymer characterization, such as polymer density and glass transitions, are addressed.