Ithaca College

Max Klemes will present
Understanding and Designing Cyclodextrin Adsorbents for Water Purification

Tuesday, October 8th 12:10 pm in CNS 333
Pizza and Beverages Provided

Students are also invited to meet informally with the speaker at 4pm in the CNS 3rd floor Atrium.

Organic micropollutants (MPs) are small organic molecules that contaminate water from anthropogenic sources. Many MPs, including per- and polyfluorinated alkyl substances (PFASs), have come under increased scrutiny because of their environmental persistence, difficult remediation, and association with various health problems. Recently, our group reported a β- cyclodextrin polymer crosslinked by tetrafluoroterephthalonitrile (TFN-CDP), that rapidly removes hundreds of MPs from water, resists fouling by natural organic matter, and can be regenerated. A study of the binding of 83 MPs under environmentally relevant concentrations revealed that TFN-CDP rapidly removes many cationic and neutral MPs, but removal of anionic MPs was relatively low. This selectivity for cations was attributed to anionic phenolate groups introduced onto the crosslinkers during the polymerization. The inability of TFN-CDP to bind anionic MPs, including anionic PFASs, is a major limitation to its broad utility and technological promise. To address this shortcoming, we reduced the nitrile groups in TFN-CDP to primary amines, which reverses its affinity towards charged MPs, with especially high affinity towards anionic PFASs. This reduced-CDP has superior PFAS removal performance at environmentally relevant concentrations when compared to the commercial benchmark granular activated carbon. These findings demonstrate the scope and tunability of cyclodextrin-based adsorbents and the promise of novel adsorbents constructed from molecular receptors.

Individuals with disabilities requiring accommodations should contact Paula Larsen at plarsen@ithaca.edu or (607) 274-3238. We ask that requests for accommodations be made as soon as possible.