Mechanochemical Degradation of PFAS by Piezoelectricity in Natural Crystals from Contaminated Subsurface = 천연 결정의 압전현상에 의한 과불화화합물 오염지반의 기계·화학적 분해

다국어 초록 (Multilingual Abstract)

This study investigates the mechanochemical degradation behavior of PFOS- and PFOA-contaminated soils using natural piezoelectric tourmaline (feruvite). During high-energy milling, structural damage and surface defect formation in tourmaline promote electron generation and transfer, thereby facilitating C–F bond cleavage and the mineralization and immobilization of released fluorine. FT-IR, ¹⁹F NMR, and XPS analyses consistently demonstrate molecular-scale decomposition of PFAS and the formation of sulfate and metal–fluoride species at both molecular and surface levels. The results provide scientific evidence supporting the feasibility of a sustainable PFAS remediation approach based on natural minerals.

국문 초록 (Abstract)

본 연구는 압전성을 갖는 천연 투어말린(feruvite)을 이용하여 PFOS 및 PFOA로 오염된 토양의 기계화학적 분해 거동을 규명하였다. 고에너지 분쇄 과정에서 투어말린의 결정 구조 손상과 표면 결함 형성이 전자 생성 및 전달을 유도하여 C–F 결합 절단과 불소의 무기화·고정화를 촉진함을 확인하였다. FT-IR, ¹⁹F NMR, XPS 분석을 통해 PFAS의 분자 구조 붕괴와 함께 황산염 및 금속-불화물 형성 등 화학적 분해가 분자·표면 수준에서 일관되게 관찰되었다. 본 연구는 천연 광물을 활용한 지속가능한 PFAS 오염토 처리 기술의 과학적 근거를 제시한다.

목차 (Table of Contents)

• CHAPTER 1. INTRODUCTION
• 1.1 Preface
• 1.2 Statement
•   1.2.1 Motivation and Aim
•   1.2.2 Scope and Scale
•   1.2.3 Problem and Approach
• CHAPTER 2. LITERATURE REVIEW
• 2.1 Contextual Study
•   2.1.1 Historical and Social Background
•   2.1.2 Environmental and Social Background
•   2.1.3 Industrial Background
•   2.1.4 Policy Background
•   2.1.5 Technical Background
• 2.2 Conceptional Study
•   2.2.1 PFAS
•   2.2.2 Piezoelectric Materials
• 2.3 Theoretical Study
•   2.3.1 Electron Generation from Piezoelectric Minerals
•   2.3.2 Lattice Defects
• 2.4 Parametric Study
•   2.4.1 Parametric Basis
•   2.4.2 Parametric Optimization
•   2.4.3 Implications
• 2.5 Previous Research
•   2.5.1 Case Studies
•   2.5.2 Research Trends
•   2.5.3 Research Gaps
• CHAPTER 3. METHODOLOGY
• 3.1 Objectives
• 3.2 Materials
•   3.2.1 Chemicals
•   3.2.2 Contaminated Soil
• 3.3 Equipment and Instruments
•   3.3.1 LC–MS/MS
•   3.3.2 XPS
• 3.4 Experimental Procedure
•   3.4.1 Post-processing
•   3.4.2 QA/QC
• CHAPTER 4. RESULTS
• 4.1 Solid PFAS Treatment
•   4.1.1 Results
• 4.2 Contaminated Soil Treatment
•   4.2.1 Results
•   4.2.2 Discussion
• 4.3 Analysis
•   4.3.1 XPS
•   4.3.2 FT-IR
•   4.3.3 NMR
• 4.4 Mass Balance
• CHAPTER 5. CONCLUSIONS AND FUTURE WORK
• Bibliography