DEVELOPMENT OF SECOND USE APPLICATIONS FOR IONOMER MATERIALS RECOVERED FROM HYDROGEN ECONOMY SYSTEMS

Perfluorosulfonic acid (PFSA) polymers are the primary membrane material used in the manufacturing of water electrolyzers and fuel cells for the hydrogen economy. The discarding of these materials, especially when they are combined with precious metals, presents an unwanted introduction of these materials into the environment. Thus, the opportunity being addressed by this SBIR proposal is the development of secondary-use applications for Perfluorosulfonic acid Polymer bearing manufacturing scrap generated by the use of such materials in the hydrogen economy equipment. We have already developed, in a previous DOE funded project, the ability to separate precious group metal (PGM) bearing PFSA scrap into PGM material largely free of PFSA , and PFSA material largely free of PGMs. This process involves the solubilizing of the polymer and then a physical separation step between the liquid PFSA containing phase and solid PGM containing phase. The first key task of this project is to quantify the degree of this separation that we can achieve between these two materials and compare it to a target to be defined here. The second key task of the project will be to develop new secondary-use applications for the recovered PFSA materials. Applications that are technically feasible, but are hampered by the high cost of the PFSA materials are the target applications. The applications and market partners for such will be carefully selected such that they meet the following criteria: not reliant on superior material properties that can only be achieved via virgin polymer and have a significant near-term demand so that processing costs will not dominate material product costs. Phase 1 work will center around measurement of the properties of new membranes made from manufacturing scrap. The fundamental properties such as mechanical strength and ionic conductivity will be studied with targets set close to those of virgin materials. At least one key application for the recovered material will be identified.