(110a) PFAS Destruction and Renewable Hydrocarbon Production

Per- and poly-fluoroalkylated substances (PFAS) are a group of compounds known for their persistence in the environment and documented impacts on human health, including various cancers. Despite regulations by the US Environmental Protection Agency to control their presence in drinking water, PFAS continue to contaminate water sources, soils, and waste streams due to their prior widespread use in products such as fire retardants, coatings for cooking utensils, and adhesives. These compounds are often referred to as "forever chemicals."

Our research investigates the behavior of four specific PFAS compounds (perfluorooctanoic acid, perfluoroheptanoic acid, heptadecafluorooctanesulfonic acid tetraethylammonium salt, and perfluorohexanesulfonic acid) within the hydrothermal liquefaction (HTL) and hydrotreatment processes. These processes aim to convert wet carbon sources, such as wastewater treatment sludge and invasive algal biomass, into renewable hydrocarbons for transportation application while mitigating landfilling needs.

This presentation will detail the observed degradation and concentration changes of the PFAS compounds in the various intermediate and product streams resulting from the HTL and hydrotreatment processes. Additionally, we will discuss current challenges in PFAS analysis.