Life Cycle Assessment of PFAS Removal from Landfill Leachate at the Laboratory Scale

Per- and polyfluoroalkyl substances (PFAS) are a group of emerging organic contaminants receiving rising attention due to the threat they may pose to human health and their strong persistence in the environment, determined by their widespread use in the market as additives, reactants, or coverings. Since the most common end-of-life of products is landfill, countless case studies have confirmed the presence of PFAS in leachates. This work aims to evaluate and compare the environmental impacts of four different PFAS removal techniques from landfill leachate through a life cycle assessment performed on laboratory tests. Global warming, particulate matter formation, and human toxicity were examined and discussed in detail, since they represent most of the final single-score impact. The toxicity contribution of the residual PFAS in the matrix was investigated, resulting almost negligible. The results highlight activated carbon, sludge disposal, and sulfuric acid as major environmental hotspots for all categories. The clariflocculation followed by activated carbon adsorption results in the least impactful technique with promising PFAS removal efficiencies, between 44.3% and 82.2% depending on carbon dosage. Very precise correlations in the trends of the impact categories and the use of different functional units were also analysed.