Removal of PFAS and pharmaceuticals from municipal wastewater using a novel β-cyclodextrin adsorbent over distinct
Emma F Shapiro1, Zhi-Wei Lin2, Edwin Saavedra Cifuentes1
1Department of Civil and Environmental Engineering, Northwestern University, Evanston, IL, 60208, USA.
Abstract:
Conventional adsorbents applied in wastewater treatment are ineffective at removing trace organic contaminants (TrOCs), including per and poly-fluoroalkyl substances (PFAS) and pharmaceuticals. Cross-linked β-cyclodextrin (β-CD) polymer adsorbents have demonstrated efficient removal of TrOCs and exhibit rapid kinetics and high adsorption capacity in wastewater. We evaluate the removal of a mixture of contaminants from wastewater by a styrene functionalized β-CD adsorbent (StyDex) through rapid small-scale column tests (RSSCTs). We found the kinetics observed in batch adsorption tests are maintained in RSSCTs. However, batch sorption kinetic constants did not match column breakthrough kinetics, due to an inability to describe complex flow-through behaviors. We correlated both batch kinetic constants and treatable bed volumes with hydrophobicity of target compounds, where PFOA and PFHxS had the highest affinity for StyDex in batch tests and the latest breakthroughs in RSSCTs. Breakthrough curves of five of the seven TrOCs were not affected by change in contact time. Conversely, decreasing the contact time led to earlier breakthrough of contaminants with the highest sorption affinity to StyDex: longer chained and sulfonated PFAS compounds. These effects were isolated in two-component competitive sorption experiments between PFOA and PFBA, and we observed the same preferential sorption of hydrophobic compounds identified in the multi-component mixture. Additionally, competitive adsorption-desorption increased with increasing contact times. We discuss how these findings are crucial for scale-up and large-scale testing of novel sorbents.
More Related Videos
05:46Identification of Pharmaceuticals in The Aquatic Environment Using HPLC-ESI-Q-TOF-MS and Elimination of Erythromycin Through Photo-Induced Degradation
Published on: August 1, 2018
09:04Identifying Per- and Polyfluorinated Chemical Species with a Combined Targeted and Non-Targeted-Screening High-Resolution Mass Spectrometry Workflow
Published on: April 18, 2019
Related Concept Videos
Bioremediation
Factors Affecting Solubility
Extracorporeal Removal of Drugs: Hemoperfusion and Hemofiltration
Microbial Bioremediation of Uranium
Microbial Bioremediation of Pesticides
Bioplastics
