Presentation Title

Treatment of AFFF Contaminated Water Using Hydrated Electron

Faculty Mentor

Jinyong Liu

Start Date

17-11-2018 10:00 AM

End Date

17-11-2018 10:15 AM

Location

C304

Session

Oral 2

Type of Presentation

Oral Talk

Subject Area

engineering_computer_science

Abstract

Per- and polyfluoroalkyl substances (PFAS) are a family of man-made toxic chemicals that fluorochemical manufacturing companies have been producing and releasing into main water systems. Infamous fluorochemicals such as perfluorooctanoic acid and perfluorooctane sulfonic acid, as well as emerging replacement chemicals such as GenX, have been used in a wide scope of application for decades polluting waters globally. One such PFAS application is aqueous film-forming foam (AFFF), a commonly-used fire suppressant that is comprised of fluorocarbons, among other materials. This investigation aims to treat AFFF-contaminated waters by cleaving (or breaking) the extremely stable C-F bond through use of a hydrated electron. Results from our work prove encouraging, although is challenged by the complexity of the AFFF mixture. Controlled experiments on pure PFAS solutions were executed to understand the extent of C-F bond cleavage (“defluorination”) as well as underlying reaction mechanisms (i.e., H/F exchange). Furthermore, investigation into the treatment system utilizing the AFFF as a baseline measure, we studied a series of system operation parameters, as well as system pH which has led to insights on how to efficiently destroy “real-world” contaminated water systems. Results from these studies have led to direct implications for treatment of PFAS-contaminated waters.

Keywords: Advanced Water Treatment, AFFF, Perfluorinated Compounds, Hydrated Electron, Water Contaminants, fluorocarbons, defluorination, Advanced Reduction Processes

Summary of research results to be presented

  • Increasing pH leads to an increase in overall fluoride release.
  • Increasing concentration of hydrated electron source leads to faster rate of defluorination over reaction-time.
  • Treatment of AFFF reaches a plateau for defluorination regardless of pH or hydrated electron concentrations.
  • Hydrated electron is effective in a wide-range of AFFF concentrations.

This document is currently not available here.

Share

COinS
 
Nov 17th, 10:00 AM Nov 17th, 10:15 AM

Treatment of AFFF Contaminated Water Using Hydrated Electron

C304

Per- and polyfluoroalkyl substances (PFAS) are a family of man-made toxic chemicals that fluorochemical manufacturing companies have been producing and releasing into main water systems. Infamous fluorochemicals such as perfluorooctanoic acid and perfluorooctane sulfonic acid, as well as emerging replacement chemicals such as GenX, have been used in a wide scope of application for decades polluting waters globally. One such PFAS application is aqueous film-forming foam (AFFF), a commonly-used fire suppressant that is comprised of fluorocarbons, among other materials. This investigation aims to treat AFFF-contaminated waters by cleaving (or breaking) the extremely stable C-F bond through use of a hydrated electron. Results from our work prove encouraging, although is challenged by the complexity of the AFFF mixture. Controlled experiments on pure PFAS solutions were executed to understand the extent of C-F bond cleavage (“defluorination”) as well as underlying reaction mechanisms (i.e., H/F exchange). Furthermore, investigation into the treatment system utilizing the AFFF as a baseline measure, we studied a series of system operation parameters, as well as system pH which has led to insights on how to efficiently destroy “real-world” contaminated water systems. Results from these studies have led to direct implications for treatment of PFAS-contaminated waters.

Keywords: Advanced Water Treatment, AFFF, Perfluorinated Compounds, Hydrated Electron, Water Contaminants, fluorocarbons, defluorination, Advanced Reduction Processes