Engineering Pfas Membrane Adsorbers

Water quality is a problem in many areas of the world and one particularly harmful type of pollutant is referred to as per-and polyfluoroalkyl substances or PFAS. PFAS are composed of a hydrophobic fluorinated carbon chain tail and a hydrophilic head group that is typically a carboxylic or sulfonic acid. PFAS have many properties that make them very useful as water and oil repellents, which made them widely used. However, this use went unregulated and now PFAS contaminate many water sources, and when ingested by people or animals, they can build up in their bodies and cause health problems. PFAS are difficult to get out of water, but one method is to use polymeric membrane adsorbers that will interact with PFAS molecules to remove them from the water. In this study, I used AGET-ATRP to attach an amine group to an ultrafiltration membrane so that the membrane was able to interact with the anionic charged head group of PFAS molecules. The surface of the membrane was tested for successful modification using ATR-FTIR spectroscopy. Dodecylbenzene Sulfonic Acid (DBSA) was used as a PFAS surrogate due to ease of quantification and was contacted with the membranes to measure absorbance during static adsorption tests. The concentration of the DBSA remaining after contact with the membrane adsorber was tested using UV-Vis spectrophotometry to make sure the membrane adsorbers are effective at removing the contaminant. Once the DBSA has been attached to the membrane adsorber, it is tested for regeneration and reusability by putting it in a basic solution so the DBSA can be released and collected. Reusability creates less waste and makes the process more economically favorable. The adsorption of PFAS helps to improve water safety and quality and improves public health by removing and containing a harmful water contaminant.