Summary

Per- and polyfluorinated alkyl substances (PFAS) comprise a class of thousands of toxic compounds that have been found in drinking water sources in 34 US states and in the blood of 97% of people tested. Exposure to PFAS has been linked to immune toxicity, cancer, high cholesterol, and several other health effects. Over 57,000 sites across the US are estimated to have PFAS pollution, and the total remediation market is estimated at $160 billion. Adsorption technologies are widely used for removing PFAS from water sources, but these produce secondary waste in the form of PFAS-laden spent sorbent media or complex regenerate solutions. Disposal or incineration of this secondary waste is costly and becoming highly regulated or even banned in some states. Enspired Solutions is commercializing a patented PFAS destruction technology called micelle-accelerated photoactivated reductive defluorination (PRD). The company is developing a micelle-accelerated PRD reactor to degrade PFAS on spent ion exchange (IX) resin and regenerate the resin for further PFAS removal. The commercial system is the size of two large refrigerators, fully automated and modular to accommodate site-specific flow rates of 1,000 to 1,000,000 gallons per day of water contaminated with ng/L to µg/L concentrations of PFAS. Treatment cost estimates are competitive with PFAS capture and disposal. The proprietary chemical formulation traps PFAS in solution inside a micelle, where an electron donor generates a hydrated electron upon exposure to ultraviolet (UV) light. The hydrated electron breaks the carbon-fluorine bonds of PFAS molecules, degrading them to environmentally benign by-products. Compared to other PFAS destruction technologies, micelle-accelerated PRD is more efficient, safer, and requires a smaller footprint. When paired with suspended spent IX resin, the positively charged resin surface can localize PFAS and the electron donor for selective PFAS destruction. Any PFAS that desorbs from the resin will be captured in a micelle in solution and similarly degraded. Bench scale micelle-accelerated PRD reactions will be performed on suspensions of IX resin loaded with PFAS from a synthetic solution. Defluorination of PFAS will be monitored in real-time as a function of UV dose and confirmed with individual PFAS compound analysis. Reaction conditions will be optimized to achieve ≥ 99% (two orders of magnitude) PFAS destruction. The reusability of the resins after micelle-accelerated PRD will be tested by measuring the adsorption capacity after regeneration, targeting 60 – 80% capacity retention after each regeneration cycle. In Phase II, testing will include a range of real PFAS-laden wastewater samples, which will have complex matrices and a broader range of PFAS compounds. Testing will also expand to other media used for PFAS adsorption (ionomers, biochar, modified cornstarch, etc.) and larger sample volumes. This system will provide a complete, on-site PFAS capture plus destruction solution that will eliminate secondary waste generation and put an end to the spread of PFAS.