Harnessing redox electro-sorbents and reactive separations for efficient PFAS remediation in water systems

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants with profound health and ecological implications. Redox-polymer materials have emerged as promising solutions for PFAS remediation, offering tailored electrochemical approaches to tackle the challenges posed by these persistent micropollutants. In this study, we present innovative strategies utilizing redox-polymer materials for efficient PFAS removal and destruction. Our investigation begins with the selective electrochemical separation and mineralization of PFAS, particularly GenX, using a redox-copolymer composed of poly(4-methacryloyloxy-2,2,6,6-tetramethylpiperidin-1-oxyl-co-4-methacryloyloxy-2,2,6,6-tetramethylpiperidine) (PTMA-co-PTMPMA). The copolymer's amine functional groups enhance affinity towards anionic PFAS, while redox-active nitroxide radicals enable controlled adsorption and desorption under electrochemical conditions. Optimized electrochemical parameters yield enhanced kinetics and substantial uptake capacities (>475 mg/g). Further exploration focuses on evaluating PTMA-co-PTMPMA for targeted electrochemical removal of PFAS contaminants, emphasizing regeneration capabilities and transitioning to continuous flow cell configurations. The study elucidates electrochemical mechanisms governing PFAS capture and release across diverse pH and water matrices, showcasing the copolymer's efficacy under varying environmental conditions. Additionally, we investigate redox-active metallopolymers to enhance electrochemical reversibility and electrosorption uptake in PFAS remediation. Synthesized metallopolymers with tailored redox potentials demonstrate superior PFAS capture and regeneration efficiencies, highlighting structure-property relationships impacting electron density and contaminant affinity. Innovative PFAS remediation techniques are then showcased, including up-concentration and utilization of PTMA-containing polymers as adsorbents. Integration of advanced oxidative processes with boron-doped diamond (BDD) electrodes achieves complete defluorination post-up-concentration, demonstrating energy-efficient solutions for comprehensive PFAS treatment. Through these investigations, this thesis underscores the efficacy and versatility of redox-polymer materials in addressing complex PFAS contamination scenarios. These findings contribute significant insights towards advancing sustainable and efficient PFAS remediation strategies crucial for safeguarding public health and environmental integrity.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Baldaguez Medina, Paola A.

Contributors dc:contributor

• Su, Xiao
• Yang, Hong
• Sankaran, R. Mohan
• Kong, Hyun Joon

• Pfas
• Electrosorption
• Redox-polymers

Statement dc:rights

• Copyright 2024 Paola Baldaguez Medina

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/125522

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F125522