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:
Closing the Loop on PFAS: Scalable BN-TiO2 Slurry Treatment for RO Concentrate Management
Abstract Submission:
Closing the Loop on PFAS: Scalable BN-TiO2 Slurry Treatment for RO Concentrate Management
Gunhak Oh, Matthew Sima, and Michael S. Wong | Rice University
Reverse osmosis (RO) is a leading technology for PFAS compliance, yet it creates a secondary liability: a PFAS-concentrated reject stream that is difficult to treat and expensive to dispose of. This study presents a scalable, post-RO treatment solution using Boron Nitride (BN)–Titanium Dioxide (TiO2) heteroaggregate slurries. Unlike complex hightemperature material synthesis, we utilized electrostatic heteroaggregation to engineer controlled interfacial contact between adsorption-active BN and photocatalytically active TiO2. This approach preserves surface functionality and is inherently scalable. We evaluated performance in high-ionic-strength matrices—simulating real-world RO concentrate—in both bench-scale settings and a 10 L pilot-scale photoreactor. Results indicate that optimizing the BN:TiO2 ratio significantly enhances PFAS removal beyond single-component controls, proving that interfacial engineering is more critical than surface area alone. Crucially, the heteroaggregates facilitated superior PFAS transformation and fluoride release compared to BN or TiO2 alone, effectively mitigating catalyst fouling. By validating a slurry-compatible process in a pilot environment, this work offers a practical engineering pathway for managing PFAS concentrates.
Reverse osmosis (RO) is a leading technology for PFAS compliance, yet it creates a secondary liability: a PFAS-concentrated reject stream that is difficult to treat and expensive to dispose of. This study presents a scalable, post-RO treatment solution using Boron Nitride (BN)–Titanium Dioxide (TiO2) heteroaggregate slurries. Unlike complex hightemperature material synthesis, we utilized electrostatic heteroaggregation to engineer controlled interfacial contact between adsorption-active BN and photocatalytically active TiO2. This approach preserves surface functionality and is inherently scalable. We evaluated performance in high-ionic-strength matrices—simulating real-world RO concentrate—in both bench-scale settings and a 10 L pilot-scale photoreactor. Results indicate that optimizing the BN:TiO2 ratio significantly enhances PFAS removal beyond single-component controls, proving that interfacial engineering is more critical than surface area alone. Crucially, the heteroaggregates facilitated superior PFAS transformation and fluoride release compared to BN or TiO2 alone, effectively mitigating catalyst fouling. By validating a slurry-compatible process in a pilot environment, this work offers a practical engineering pathway for managing PFAS concentrates.