Lauren Turner is PhD student in Civil Engineering at Queen's University co-supervised by Dr. Bernard H. Kuper and Kela P. Weber. Her research focus is the remediation of Per-and Polyfluoroalkyl substances (PFAS) in solid media. Her current work is investigating the remediation of soils via ball milling. Lauren obtained her B.A.Sc (Eng) in Geological Engineering at Queen's University.
Mechanochemical Destruction of Per- and Polyfluoroalkyl Substances (PFAS) via Ball Milling
Per- and polyfluoroalkyl substances (PFAS) are manmade, fluorinated organic chemicals which have been identified as persistent organic pollutants (POPs). PFAS have surface active properties that have made them suitable for applications in oil and water resistant products, as well as fire-fighting foam for fuel-based fires. No feasible, on-site remediation strategies exist to treat PFAS impacted soils. Mechanochemical destruction via a planetary ball mill evaluated the destruction of PFOS and PFOA amended sand using a 23 factorial design which evaluated the effect of sand mass, KOH as a co-milling reagent and water saturation. Milling experiments achieved destruction of up to 98% PFOS and 99% PFOA in dry amended sand without the addition of a co-milling reagent. Saturation was determined to be a significant hindrance on the mechanochemical destruction of PFOS and PFOA. A maximum of 89% of fluoride was recovered from sand with KOH as a co-milling reagent. Milling experiments were conducted on soils from a Canadian firefighting training area. Ball milling of firefighting foam impacted soils demonstrated that PFOS concentrations can be reduced by up to 96% in real site soils.