Development of a Passive Sampler for Detecting PFAS Using Polymer-Organosilica Hybrid Adsorbents

Name: Heather Hartmann
Majors: Chemistry, Spanish
Advisors: Dr. Paul Edmiston, Dr. Karl Feierabend
Per-and polyfluoroalkyl substances (PFASs) are environmental contaminants of emerging concern due to their persistence and evidence of adverse health impacts. Environmental monitoring to measure PFAS is of high need to assess water quality and to understand the fate and transport of PFAS. Passive samplers offer advantages in efficiency and cost compared to traditional grab sampling. Swellable organically modified silica modified with crosslinked polyethyleneimine (PEI-SOMS), a weak ion exchange polymer was used in the passive sampling devices. Copper (II) ions were bound to the resin and increase the valency to enhance adsorption of short chain PFAS. Experiments measuring adsorption capture versus time showed the responseto be an equilibrium uptake for all PFAS with short chain carboxylic acids coming to equilibrium after 6 days. Other compounds such as longer chain carboxylates and the sulfonic acids require longer to come to equilibrium (greater than 12 days). The sampling rate was linear for concentrations from 10-50,000 ng/L (3 days sampling time) with an open mesh design using copper PEI-SOMS. The samples showed a high uptake rate, about 5-10 times faster, compared to other passive samplers attributed to the open meshhousing and expanded pores of the adsorbent. I really enjoyed getting to learn more about passive sampling and more about chemistry techniques that I can use beyond Wooster. Future work can also be done to develop a device that homeowners can potentially use to detect PFAS in their own water.