K.C. Tam, E. Ojogbo
University of Waterloo,
Canada
Keywords: cellulose, PFAS
Summary:
Per- and polyfluoroalkyl substances (PFAS) are a class of synthetic chemicals widely used in industrial and consumer applications due to their unique properties, such as thermal and chemical stability and resistance to degradation. While these characteristics make PFAS valuable in manufacturing, they also contribute to their environmental persistence, earning them the label "forever chemicals." PFAS contamination in water sources has emerged as a global crisis, causing significant environmental and public health risks. Exposure to PFAS has been linked to adverse health effects, including cancer, endocrine disruption, and developmental issues in children. Addressing this widespread contamination is critical for environmental and health reasons. Short-chain PFAS (C4–C6) are especially challenging to adsorb due to their higher mobility in water, lower hydrophobicity, and reduced affinity for conventional adsorbents. Unlike their long-chain counterparts, short-chain PFAS exhibit weaker hydrophobic interactions, making them more challenging to adsorb using traditional materials like granular activated carbon. Consequently, innovative and sustainable solutions are required to remove both long- and short-chain PFAS from water. This research investigates the use of cellulose nanocrystals (CNCs) as a novel and sustainable adsorbent for PFAS remediation. CNCs, derived from renewable biomass, are biodegradable, eco-friendly materials with unique properties, including a high surface area, tunable surface chemistry, and excellent mechanical strength. These features make CNCs promising candidates for environmental applications, particularly for the adsorption of persistent contaminants such as PFAS. By modifying the surface of CNCs, we have developed a tailored adsorbent with affinity for both long- and short-chain PFAS molecules. In this study, the adsorption performance of the modified CNCs was systematically evaluated under varying conditions, including pH, ionic strength, and PFAS concentrations. Preliminary results demonstrate the adsorption of PFAS, highlighting the potential of CNCs for water treatment applications. The adsorption mechanism is hypothesized to involve a combination of electrostatic interactions, hydrophobic partitioning, and fluorous interactions. The broader implication of this research extends beyond the immediate benefits of PFAS removal. CNCs, as a renewable and biodegradable material, align environmental remediation strategies with sustainability goals. The reduced carbon footprint and inherent scalability of CNC production further reinforce its potential to address PFAS contamination on a global scale. Moreover, this study highlights the importance of addressing short-chain PFAS, which are increasingly used as substitutes for longer-chain variants but pose equivalent risks to human health and the environment. This presentation will provide an overview of the CNC-based adsorbent and kinetics of PFAS adsorption. These results represent a pivotal advancement in developing eco-friendly, scalable solutions for PFAS removal, addressing critical environmental and public health challenges associated with PFAS contaminants.