2024 AIChE Annual Meeting

(186a) Towards the Complete Mineralization of PFOA with a Pilot-Scale UV-Light, Boron-Nitride—Based Recirculating Reactor Unit

Authors

Juan Donoso - Presenter, Rice University
Guo Chen, Tokyo Institute of Technology
Kimberly N. Heck, Rice University
Mohamed Ateia, US Environmental Protection Agency
Michael Wong, Rice University
Heterogeneous photocatalysis is a potential PFAS destruction approach, as it requires few chemical additives and is relatively energy efficient. However, low-activity materials, byproduct formation, and difficulty treating large water volumes limit wide-scale adoption. In this study, we demonstrate the multi-liter degradation of perfluorooctanoic acid (PFOA) using boron nitride (BN) as a slurry under UV illumination and recirculating flow with a commercial UV flow reactor. With BN, the UV flow reactor destroyed PFOA to near completion after 6 h, quantified as >99% defluorination (total fluorine content converted into fluoride ions). With P25 TiO2 for comparison, the UV flow reactor showed 40% defluorination after 6 h. Without any photocatalyst, the UV flow reactor showed 34% defluorination. Additionally, BN is only minorly inhibited by cosolute anions in tap water. We discuss the important operational parameters and their impact on PFOA defluorination extent. These results show a viable path towards real-world application of heterogeneous photocatalysis to manage PFAS contamination.