PFAS treatment with granular activated carbon and ion exchange resin: Comparing chain length, empty bed contact time, and cost. (December 2021)

• Record Type: Journal Article
• Authors: Murray, Conner C.; Marshall, Robert E.; Liu, Charlie J.; Vatankhah, Hooman; Bellona, Christopher L.
• Is Part Of: Journal of water process engineering. Volume 44(2021)
• Publication Date: 2021-12
• Subjects: PFAS -- Adsorption -- Activated carbon -- Ion exchange -- Cost analysis; Water-supply engineering -- Periodicals; Saline water conversion -- Periodicals; Seawater -- Distillation -- Periodicals; Sanitary engineering -- Periodicals; Sewage -- Purification -- Periodicals; 627
• DOI: 10.1016/j.jwpe.2021.102342
• Languages: English
• ISSNs: 2214-7144

Abstract

Abstract: Per- and polyfluoroalkyl substances (PFASs) are among the most recalcitrant chemicals ever manufactured and are associated with substantial global environmental challenges. PFAS removal performance of granular activated carbon (GAC) and ion exchange resin (IX) was evaluated and compared using a segmented column system with full scale media under continuous flow conditions. Results from the PFAS breakthrough analysis established via column operation under different empty bed contact times (EBCTs) was used to characterize the mass transfer zone (MTZ) of multiple PFASs and evaluate optimum EBCTs for GAC and IX treatment. The height of the MTZ corresponded to PFAS chain length and functional group, where the poorly removed short chain perfluoro-carboxylic acids exhibited the longest MTZ. Elongated PFAS MTZs justified longer EBCTs required for treatment of short chain PFAAs compared to long chain PFAAs for GAC and IX. In addition, a cost sensitivity analysis was employed to demonstrate how unit media cost, changeout frequency, and treatment goal feasibility dictated annual operation and maintenance (O&M) costs associated with GAC and IX installations. IX was found to the most cost-effective adsorbent for the removal of long and short chain PFASs compared to GAC. Results from the cost analysis indicated that adsorbent selection was the most critical factor dictating treatment cost with marginal impact from unit media cost or expected changeout frequency. Graphical abstract: Unlabelled Image Highlights: IX outperformed GAC for removal of short and long chain PFAS. Columns in series reflect GAC and IX adsorption of PFAS as impacted by EBCT. Treatment cost impacted by treatment goal, unit price and changeout frequency