(219g) Evaluating Green Novel Deep Eutectic Solvents for Pfas Removal from Water; COSMO Simulation with Experimental Validation

In recent years, perfluoroalkyl substances (PFAS), also known as forever chemicals have been identified as global pollutants. Due to their unique chemical properties, such as high solubility in water and extreme persistence in the environment, PFAS have raised concerns about their potential human toxicity. As a result, there is a growing need to understand the fate, transport, and remediation of these chemicals in the environment as conventional water treatment methods, such as coagulation/flocculation, filtration, and chlorination are ineffective in removing them. Consequently, it is crucial to develop an efficient method that can remove PFAS effectively. This study used a computational approach to systematically screen over one hundred novel and environmentally friendly deep eutectic solvents (DES) using the Conductor-like Screening Model for Real Solvents (COSMO-RS) to investigate the removal mechanisms of two specific PFAS compounds, perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), from water. DES are a mixture of two compounds (a hydrogen bond donor or HBD and a hydrogen bond acceptor or HBA) that conjugate through hydrogen bonding, resulting in a deep depression of the melting point of the mixture and an increase in solvent properties. The DES-based separation was evaluated by predicting various thermodynamic properties, such as sigma profiles, sigma potentials, logarithmic activity coefficient (ln(γ)), and excess enthalpy (H_E) of absorption. The predicted thermodynamic properties are further validated with experimental results. In addition, an environmental health and safety assessment was performed on the DES components to evaluate their toxicity and impact on the ecosystem. Overall, tetra-alkyl ammonium bromide-based DES showed higher separation efficiency due to their affinity for PFOS and PFOA.