Innovative PFAS Treatment Proves Less Is More

By Kevin Westerling,
@KevinOnWater

Per- and polyfluoroalkyl substances (PFAS), persistent throughout the environment and subject to recently finalized U.S. EPA regulation, can now be captured and neutralized in a single, integrated system that adds to the growing set of remedies for these so-called “forever chemicals”.

The treatment system, which was developed by chemical engineers at the University of British Columbia (UBC), incorporates elements familiar to PFAS removal — activated carbon and ultraviolet (UV) light — but features a patented UV catalyst that is much more energy-efficient, requiring only minimal light. It also works on contaminants beyond PFAS and can be easily implemented in all sorts of locales and treatment schemes.

For more detail on how the system works and its ultimate potential, I consulted researchers Dr. Raphaell Moreira and Dr. Johan Foster, who led the study, for the following Q&A.

Activated carbon filtration is well-known to be effective for PFAS removal, but the UBC system adds a special catalyst to enhance treatment. Can you describe the catalyst and how it improves removal?

RM: Our technology utilizes a novel catalyst composed of a biomass-derived carbon support impregnated with a photoactive metal oxide. This dual functionality enables both adsorption and photodegradation of PFAS, offering superior removal efficiency compared to traditional methods. Our use of a biomass-derived carbon support contributes to a more sustainable approach to PFAS removal.

Can the technology be brought to scale to help utilities meet PFAS removal mandates?

RM: The technology can be easily scaled up to meet the growing demand for PFAS removal. It's also applicable to various settings, including industrial wastewater treatment, drinking water purification, and remediation of contaminated sites.

Is it effective for other contaminants? Which ones?

RM: While primarily designed for PFAS, the catalyst may also be effective for other organic contaminants that can be adsorbed and photodegraded.

Where else might it be applied for PFAS removal?

JF: The technology can be applied beyond traditional drinking water treatment facilities. It is suitable for use in industrial wastewater treatment, remediation of contaminated groundwater, and clean-up efforts at environmental spill sites. Additionally, it can be integrated into decentralized systems for point-of-use applications, offering flexibility for various locations including remote areas, military bases, and industrial facilities with specific PFAS concerns.

How is it installed/implemented in a treatment plant?

JF: The catalyst-based system can be incorporated into existing treatment infrastructure with relative ease. It can be integrated as an additional filtration step or as a replacement for conventional activated carbon filters. The system involves housing the catalyst material in fixed-bed reactors (or other types), depending on the specific plant setup. The modular design ensures scalability and adaptability, making it feasible to upgrade or retrofit current systems without significant disruption.

What are the cost and O&M implications?

JF: The use of a biomass-derived carbon support provides cost advantages by reducing reliance on traditional activated carbon. The catalyst's dual functionality of adsorption and photodegradation means fewer resources are needed for replacement and disposal, lowering overall operating expenses. Maintenance is simplified, as the catalyst does not require frequent regeneration, and the UV systems used for photodegradation are designed for energy efficiency. Overall, this results in lower lifecycle costs compared to standard PFAS treatment options, making it economically viable for large-scale deployment.

For more information, see the press release announcing the UBC system and research paper published in Nature Communications Engineering.

See also Water Online’s Guide to PFAS Treatment in Drinking Water.