Influence of Ion Pairing on Sulfate Radical Mediated PFAS Oxidation

* Honorable Mention *

PROJECT NUMBER: 30

AUTHOR: Allison Vanderfeen, Chemical and Biological Engineering | MENTOR: Shubham Vyas, Chemistry

ABSTRACT

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Perfluoroalkyl substances (PFASs) are used in numerous consumer products due to their inert nature and unique chemical properties. They are environmentally persistent, and their widespread use has led to contamination of biome globally. Chemical oxidation by activated persulfate is being explored as a method to remediate perfluorocarboxylic acids (PFCAs), a prevalent subclass of PFASs. The active species in this technology is sulfate radical, which oxidizes the carboxylate group of these compounds. Ion-pairing between PFCAs and the counter cations including sodium and potassium is hypothesized to influence oxidation kinetics. This research tested this hypothesis. In particular, we compared if ion pairs affect oxidation kinetics based purely on the change in electrostatics or whether they are more intimately involved in the mechanism. Density functional theory was used to investigate parameters of electron transfer kinetics.

VISUAL PRESENTATION

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AUTHOR BIOGRAPHY

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Allison is a senior graduating in May with a degree in Chemical Engineering and a minor in Biomedical Engineering. She has conducted research for the chemistry department two years in a row, first with Professor Stephen Boyes on the Release of Nile Red via pH Responsive Nanoparticles, and second with Professor Shubham Vyas on the Influence of Ion Pairing on Sulfate Radical Mediated PFAS Oxidation. During her time at Mines, Allison has enjoyed conducting undergraduate research, and she hopes to continue to pursue research in her career path.

Sponsored by Phillips 66