The removal of short‐chain and long‐chain perfluoroalkyl acids and sulfonates via granular activated carbons: A comparative column study

Abstract Per‐ and polyfluoroalkyl substances (PFAS) are contaminants of emerging concern. Granular activated carbon (GAC) is an adsorbent currently in use in removing long‐chain PFAS from water. However, there are few studies that examine short‐chain PFAS removal with GAC. The present Rapid Small‐Scale Column Test study compares the removal of a suite of both long‐ and short‐chain PFAS from groundwater. The results show that re‐agglomerated, bituminous coal‐based GACs, whether virgin or reactivated, are capable of effectively removing long‐ and short‐chain PFAS with four or more perfluorinated carbons. It was also observed that perfluorobutanoic acid, a perfluorinated carboxylic acid with just three perfluorinated carbons, reached breakthrough far more quickly than all other PFAS in this study. Coconut‐based and pool reactivated carbons, respectively, lasted 9 to 18% as long, and 43 to 57% as long, as the coal‐based carbons studied prior to breakthrough of the PFAS. The results indicate that properly selected GACs (reagglomerated bituminous coal‐based, virgin or reactivated), are a viable treatment option for PFAS contamination in water for all but the shortest perfluorinated carboxylic acids.