University of Washington
Dr. Pinkard is a subject matter expert on reaction kinetics and reaction mechanisms in supercritical water, with 10+ peer-reviewed publications. He is a current postdoctoral fellow in the Novosselov Research Group at the University of Washington, leading efforts to develop a mechanistic and kinetic understanding of the degradation of PFAS in supercritical water, and heavily involved in the development of a field-deployable supercritical water reactor for destruction of hazardous wastes. Dr. Pinkard is also the co-founder and Chief Science Officer of Aquagga, which is working to deploy novel technologies for end-of-life PFAS destruction.
Destruction of Per- and Polyfluoroalkyl Substances (PFAS) in Supercritical Water
End-of-life disposal of PFAS with complete defluorination (cleaving all C-F bonds) is needed to eliminate the risk of subsequent environmental re-contamination, or future liability. Supercritical water oxidation (SCWO) is an effective and efficient process for waste destruction, and our previous research suggests that the SCWO process can be suitable for the destruction of PFAS-rich wet wastes, including AFFF and IXR regeneration brine. We will present experimental results from batch reactor experiments where PFOS is oxidized in supercritical water amended with H2O2 at temperatures from 400 to 500 °C and reaction times from 15 to 360 min. Ion-selective electrode (ISE) is used to quantify defluorination, while LC-MS/MS, and Q-TOF-MS are used to identify and quantify the intermediate liquid products. Potential engineering strategies to increase the defluorination rate will be discussed. Recent progress toward constructing a field-deployable, continuous SCWO reactor for waste destruction will also be presented.