Summary Contamination of water bodies with residual PFAS (per- and polyfluoroalkyl substances), aka “forever chemicals” have become a pervasive and widespread problem throughout the USA and worldwide despite ongoing regulations and policies to reduce and eliminate their prevalent use in manufacturing of many products. These fluorocarbon structured chemicals are known to collect in fish, animal tissues, and are increasingly being detected in blood serum samples of humans, with determined links to health degradation issues in growth and development, reproduction, thyroid function, liver damage, disruptions of immune system, and links to increased rates in cancer. Water supplies in 66 regions across the USA serving 6 million people had at least one or more PFAS-type contamination level at or above the EPA’s safety limits. We seek to propose and demonstrate a new phase-change rotary distillation-purification system and method that should completely remove these chemicals from drinking water supplies, using a technology that is highly efficient and scalable in size, from portable up to industrial systems. The technology utilizes energy recovery and operates at low-power and low-specific energy, and has a cost-effective pathway for large-scale commercialization in homes and scalable to industrial wastewater purification requirements. Earlier versions of this technology have been NASA-validated, however, we advanced certain key heat transfer mechanisms that achieve a 10x increase above reported boiler-condenser heat transfer coefficients for known and commercially available phase-change distillation technologies. Previous testing demonstrated a 10-fold increase in heat transfer efficiency through testing with Sandia National Labs and Cedars Sinai Medical Center, using inexpensive components with instrumented earlier bench-model testing. References show that phase-change purification by traditional distillation (high-power, with no energy recovery) removes all PFAS contaminations in water samples, but these technologies are immensely cost-prohibitive with no pathway for cost-effective application uses or commercialization. Specific aims propose testing several new key technology features beyond previous testing, which should demonstrate a cost-effective pathway for commercialization. These technology features include testing with and without PFAS contaminations the efficacy of a new rotary liquid-vapor seal that is exceedingly low-cost, near unlimited life, and very low frictional drag; self-cleaning features that would automatically maintain long operation with high- performance; and testing a conceptually new centrifugal pump that theoretically is capable of removing the fresh and waste water streams from sub-atmospheric pressure operation to above atmospheric pressures at very low power.

Narrative The goal of this proposal is to demonstrate the successful PFAS removal by a new rotary distillation approach utilizing energy recovery with very high thermodynamic efficiencies. Solving key technical and scientific barriers plaguing previous distillation methods will offer widespread commercialization and public adoption.