Perfluorobutanesulfonic Acid (PFBS)

PFBS is a synthetic, short-chain PFAS with a fully fluorinated four-carbon chain attached to a sulfonic acid group. In water, it occurs predominantly as the negatively charged perfluorobutanesulfonate ion. It is environmentally persistent and can be difficult to remove using conventional treatment. Granular activated carbon generally captures PFBS less effectively than longer-chain PFAS such as PFOS, making it an important target for more selective water treatment materials.