Grantee Research Project Results
Remediation of PFAS Contaminated Soils and Sediments
EPA Grant Number: SU840140Title: Remediation of PFAS Contaminated Soils and Sediments
Investigators: Meegoda, Jay N , Rodriguez-Freire, Lucia , Kewalrmani, Jitendra , Wang, Boran , Marsh, Richard , McGlew, Brian
Institution: New Jersey Institute of Technology
EPA Project Officer: Spatz, Kyle
Phase: I
Project Period: December 1, 2020 through November 30, 2021
Project Amount: $25,000
RFA: P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet (2020) RFA Text | Recipients Lists
Research Category: P3 Awards , P3 Challenge Area - Sustainable and Healthy Communities
Description:
Per- and Polyfluorinated Alkyl Substances (PFAS) are a large and complex class of anthropogenic compounds produced and distributed since the 1950s on the global market. The unique physicochemical properties of PFAS render them toxic, bio-accumulative, and persistent in the environment. PFAS have been detected in soils and sediments from exposure to impacted media, e.g., landfill leachate or biosolids, direct contaminated discharge, and contaminant transport from atmospheric deposition. Soils and sediments can act as secondary sources of PFAS for groundwater and surface water, leading to bioaccumulation in micro-invertebrates, other organisms in the aquatic food web, and ultimately humans. There are currently no proven technologies that can degrade the PFAS in the soil and sediments in a cost-effective, environmentally-friendly, and energy-efficient manner. The overall objective of this project is to explore the technical feasibility of using ultrasound to degrade perfluoroalkyl acids (PFAAs), specifically perfluorooctane sulfonate (PFOS) and perfluorooctane carboxylate (PFOA), in soils and sediments.
Approach:
In this project, a novel ultrasound delivery method is designed to generate acoustic cavitation that combines two different ultrasonic devices to produce an intense ultrasonic field: a horn (or probe) type low-frequency transducer and the submersible (or plate) type high-frequency transducer. The low-frequency horn transducer provides agitation in the system, stirring up solids, detaching contaminants from the surface of solids, and releasing them to the bulk solution. The high-frequency plate transducers induce acoustic cavitation in the system, which initiates the sonochemical degradation of pollutants through pyrolysis and radical reactions. In this study, the key parameters such as frequency, power intensity, and solvent ratio, that influence the sonolytic decomposition of PFAS, will be optimized to ensure maximum degradation and energy-efficiency. The analytical techniques of calorimetry method, potassium iodide (KI) dosimetry, Malvern Nano Zetasizer, and Malvern NanoSight ns300 and sono-chemiluminescence (SCL) will be used to determine the distribution of heat, radicals, and nano-bubbles (size and zeta potential). The extent of PFAS degradation will be quantified using an Agilent 6470 Triple Quadruple LC/MS, as well as a Shimadzu Total Carbon Analyzer, and a fluoride Ion Selective Electrode.
Expected Results:
This project is based on existing science for degradation of the persistent organic pollutants (POPs) in water using acoustic cavitation. The proposed is a novel concept where energy delivery is optimized and implemented for remediation of pollutants in soils and sediments. In Phase I of the project, the research team will build the bench-scale sonication reactor for investigating the feasibility of the proposed technique for the remediation of soil and sediments contaminated with PFAS, specifically PFOS and PFOA. The correlation of the sonolytic degradation of PFAS with sonochemical characteristics including reactive species generation and heat distribution will be observed using KI dosimetry and calorimetry. This alternative treatment approach is expected to provide an efficient and sustainable approach for the treatment of emerging contaminants from affected soil and sediments.
Publications and Presentations:
Publications have been submitted on this project: View all 1 publications for this projectJournal Articles:
Journal Articles have been submitted on this project: View all 1 journal articles for this projectSupplemental Keywords:
Emerging Contaminants, PFAS, PFOA, PFOS, Soil Remediation, Sediment Remediation, Sonication, Acoustic Cavitation, Sonochemical Degradation, PyrolysisProgress and Final Reports:
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.