2026 Student Poster Presentation Competition
WQRF and Pentair Water Solutions are hosting current undergraduate and postgraduate students interested in drinking water to participate in a competitive call for posters. Posters will be displayed at the annual Water Quality Association's (WQA) Convention + Expo in Miami, Florida, on April 29 and 30, 2026.
Abstract Submission:
Upcycling Soybean Hulls into Activated Carbon for Effective Removal of PFAS in Water Treatment
Abstract Submission:
Upcycling Soybean Hulls into Activated Carbon for Effective Removal of PFAS in Water Treatment
Faisal Ahmed and Mahmut S. Ersan | University of North Dakota, Department of Civil Engineering
Per- and polyfluoroalkyl substances (PFAS) are persistent chemicals increasingly detected in drinking-water sources and have triggered stricter regulatory limits, creating an urgent need for affordable treatment options suitable for point-of-use (POU) and point-of-entry (POE) applications. Activated carbon is widely used for PFAS control, yet performance gaps remain for short-chain PFAS and costs can be limiting for broad implementation. The objective of this study is to upcycle soybean hulls into high-performance activated carbon and quantitatively compare pristine and magnetically enabled soybean-hull carbons against a commercial carbon for removing short- and long-chain PFAS relevant to drinking-water treatment. Pristine soybean hull activated carbon (SHAC) was synthesized using chemical activation routes (ZnCl₂ and KOH assisted) and compared with a magnetically enabled composite (M-SHAC) produced via Fe₃O₄ co-precipitation to enable rapid separation and potential operational advantages. Sorbents were characterized using BET surface area and pore distribution analysis, FTIR for functional groups, pH at point of zero charge (pHₚzc), SEM/EDS for morphology and elemental composition, and TGA for thermal stability. Batch adsorption tests evaluated six PFAS (PFBA, PFBS, PFHxA, PFHxS, PFOA, PFOS) at an initial concentration of 1 mg/L across increasing carbon doses (0.5-20 mg). SHAC demonstrated the strongest overall performance, achieving near-complete removal of almost all PFASs at low dose (e.g., 98% PFOA removal at 0.5 mg) and substantial uptake of short-chain PFBA (69% at 0.5 mg and 83-87% at 10-20 mg), which is attributed to its exceptionally high surface area (1,175 m² g⁻¹), larger total pore volume (0.54 cm³ g⁻¹), and higher pHpzc (10.5) relative to commercial F400 (1,005 m² g⁻¹, 0.49 cm³ g⁻¹, pHpzc = 9.5). M-SHAC showed selective uptake, with excellent removal of long-chain PFAS at ≥10 mg while enabling magnetic recovery, but lower affinity for short-chain PFAS due to reduced microporosity after Fe₃O₄ loading. In contrast, F400 showed the weakest performance for short-chain PFAS even at higher doses. Ongoing work will add adsorption kinetics/isotherms and validation in realistic matrices (surface water and wastewater) to support POU/POE deployment.
Per- and polyfluoroalkyl substances (PFAS) are persistent chemicals increasingly detected in drinking-water sources and have triggered stricter regulatory limits, creating an urgent need for affordable treatment options suitable for point-of-use (POU) and point-of-entry (POE) applications. Activated carbon is widely used for PFAS control, yet performance gaps remain for short-chain PFAS and costs can be limiting for broad implementation. The objective of this study is to upcycle soybean hulls into high-performance activated carbon and quantitatively compare pristine and magnetically enabled soybean-hull carbons against a commercial carbon for removing short- and long-chain PFAS relevant to drinking-water treatment. Pristine soybean hull activated carbon (SHAC) was synthesized using chemical activation routes (ZnCl₂ and KOH assisted) and compared with a magnetically enabled composite (M-SHAC) produced via Fe₃O₄ co-precipitation to enable rapid separation and potential operational advantages. Sorbents were characterized using BET surface area and pore distribution analysis, FTIR for functional groups, pH at point of zero charge (pHₚzc), SEM/EDS for morphology and elemental composition, and TGA for thermal stability. Batch adsorption tests evaluated six PFAS (PFBA, PFBS, PFHxA, PFHxS, PFOA, PFOS) at an initial concentration of 1 mg/L across increasing carbon doses (0.5-20 mg). SHAC demonstrated the strongest overall performance, achieving near-complete removal of almost all PFASs at low dose (e.g., 98% PFOA removal at 0.5 mg) and substantial uptake of short-chain PFBA (69% at 0.5 mg and 83-87% at 10-20 mg), which is attributed to its exceptionally high surface area (1,175 m² g⁻¹), larger total pore volume (0.54 cm³ g⁻¹), and higher pHpzc (10.5) relative to commercial F400 (1,005 m² g⁻¹, 0.49 cm³ g⁻¹, pHpzc = 9.5). M-SHAC showed selective uptake, with excellent removal of long-chain PFAS at ≥10 mg while enabling magnetic recovery, but lower affinity for short-chain PFAS due to reduced microporosity after Fe₃O₄ loading. In contrast, F400 showed the weakest performance for short-chain PFAS even at higher doses. Ongoing work will add adsorption kinetics/isotherms and validation in realistic matrices (surface water and wastewater) to support POU/POE deployment.