Date of Award

2024-08-01

Degree Name

Doctor of Philosophy

Department

Chemistry

Advisor(s)

Dino Villagrán

Abstract

Poly- and per-fluoroalkyl substances (PFAS) are a class of artificially made chemicals whose carbon chains are fully or partially fluorinated. Due to their persistent and pervasive distribution and their adverse effects on human health, the removal of PFAS from the environment has been the focus of current research. This project explores the use of engineered nanomaterials for the effective removal of PFAS through various adsorption and catalytic degradation methods. First, a comprehensive review of recent studies highlights the significant potential of various nanomaterials, including carbon-based, non-metal, single-metal, and multi-metal nanomaterials, for PFAS remediation. These materials are evaluated for their performance, mechanisms, and conditions in water treatment applications, emphasizing the opportunities for further development in this field. Subsequently, nano-MgAl2O4 modified carbon nanotubes (CNTs) were synthesized and used for the removal of perfluorooctanoic acid (PFOA) from drinking water and brackish groundwater, achieving over 99% removal within 3 hours under mild alkaline conditions (pH 7.5-9.0). Additionally, hexagonal boron nitride (h-BN), an electrochemically active semiconductor, was modified with UiO-66 (UiO-66@BN) to enhance proximal adsorption to catalytic sites, facilitating a "trap-and-zap" mechanism. This modification resulted in the removal of 99.5% of PFOA and 70% defluorination at an environmentally relevant concentration of 100 μg/L within 3 hours at pH 4.5, with an electrical energy per order (EE/O) of 6.1 kWh/m3, demonstrating its potential as an electrode for PFOA electrochemical oxidation. Overall, this project underscores the potential of nanomaterials in the remediation of PFAS from the environment, providing insights into their mechanisms of action, performance, and the challenges that need to be addressed.

Language

en

Provenance

Received from ProQuest

File Size

133 p.

File Format

application/pdf

Rights Holder

Sheng Yin

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