PFASelect: Selective PFAS removal from aqueous media through novel and regenerable ion exchange materials

Perfluorinated and polyfluorinated alkyl substances (PFAS), also known as “forever chemicals”, are classified as (very) persistent with some being toxic and in addition either bioaccumulative or (very) mobile. The classifications as PBT, PMT or vPvM therefore pose a far-reaching risk to humans and ecosystems. Moreover, concentrations of these substances above the health guideline value are currently detected in 14.3% of blood samples from young people in Europe. The aim of the EU according to the Green Deal is therefore to reduce the exposure of humans and ecosystems, e.g. through the Chemicals Strategy for Sustainability, the Regulation on Persistent Organic Pollutants, the REACH Regulation, the Drinking Water Directive and the new editions of environmental quality standards and Groundwater Directive. The transboundary nature of environmental problems and water bodies such as the river Inn makes cross-border cooperation indispensable.

In particular, the entry into the environment via contaminated process and waste water as well as uptake via contaminated groundwater and drinking water must be avoided. Current treatment and remediation processes, such as adsorption on activated carbon, are inefficient for certain PFAS (especially short-chain ones) and problematic if competing substances such as dissolved organic substances and anions (e.g. chloride, sulphate) are present. Furthermore, activated carbon can only be regenerated to a limited extent, which makes it a disposable fossil product.The development of highly efficient, highly selective and regenerable ion exchange materials based on perfluoroalkyl chains represents a promising solution. In a novel approach, a macroporous, amino-modified alkyl-based polymer is to be grafted with fluoroalkylated substances based on imidazole (“grafting-to”). The aim is to use a dual deposition mechanism that synergistically couples electrostatic and fluorophilic interactions. A comparison with commercially available materials (activated carbon, ion exchangers) will be carried out. Characterization and process engineering process development and simulation are to be carried out. The high-performance resins are to be regenerated by elution and oxidation using non-thermal plasma. High-performance PFAS analysis will be established. Hydraulically optimized granulates will be produced and the most promising materials will be scaled up in pilot tests. Pilot sites on both sides of the program area (i.e., Bavaria/Germany and Tyrol/Austria) will be selected and pilot plants will be developed, built and operated. The success of the project should help to raise awareness of the PFAS problem among experts and the public and present available solutions.