Pilot Study Evaluates PFAS Treatment Technologies At WEST Center

A research team at the WEST Center has launched a pilot study aimed at advancing new techniques for removing and destroying per- and polyfluoroalkyl substances (PFAS) in wastewater. This is an especially urgent effort as existing physicochemical processes in wastewater treatment plants are not designed to sustainably remove and destroy PFAS to the new, and increasingly strict, regulatory standards.

The project, which began in September 2025, focuses on developing an innovative and cost-effective PFAS treatment technique that can separate and destroy PFAS from wastewater. The approach being tested utilizes a two‑stage process combining: 1) foam fractionation to separate PFAS from wastewater; and 2) electrooxidation (EO) to destroy the concentrated contaminants. Researchers are targeting the wastewater centrate side stream (Figure 1) in their study. Centrate was selected for treatment due to its higher concentration of PFAS, high concentration of polymer additives that are already present to help support foam formation, and lower stream flow.

The study is being conducted in partnership with Pima County, with principal investigators (PIs) Dr. Vicky Karanikola from the University of Arizona, and Jeff Prevatt of the Pima County Regional Wastewater Reclamation Department (RWRD). Ovivo Technologies, a global provider of water and wastewater treatment systems, is supplying the pilot‑scale foam fractionator and electrooxidation units.

Two‑Phase Pilot Project
brThe project will unfold in two major phases.
Phase 1 focuses on pilot‑scale testing foam fractionation technology to treat various centrate matrices. This phase utilizes commercially-available equipment from Ovivo Technologies that takes advantage of PFAS’s affinity to partition to foam. PFAS are surfactants with a unique dual nature: they have a hydrophilic ("water-loving") head and a hydrophobic ("water-fearing") tail. This structure causes them to naturally concentrate at air-water interfaces, such as on the surface of bubbles (i.e. foam).

During this stage of the project, the team will evaluate PFAS removal in multiple types of centrate—including surrogate baseline samples and samples from a range of dewatering processes such as screw press, centrifuge (Tres Rios), and belt filter systems. Several municipalities have also committed to providing centrate samples, allowing researchers to test the process across diverse wastewater profiles. Additionally, operational parameters such as pH, polymer selection, and removal efficiency will also be optimized for the different types of centrate.

PFAS analyses will be performed onsite at WEST Center using Liquid Chromatography-Tandem Mass Spectrometry (LC/MS‑MS), following EPA Method 1633.

Phase 2 will expand the pilot to integrate both foam fractionation and electrooxidation (EO). Researchers will investigate the destruction efficiency of EO on concentrated PFAS and, importantly, study the nature of the resulting byproducts—seeking to determine whether the products formed after EO are inert and to what extent.

Research Team and Support
Pilot testing is being conducted in the WEST Center High Bay with efforts led by research scientist Dr. Jack Welchert, along with Pima County intern and University of Arizona environmental engineering student, Hannah Melius. The project is funded by the Water and Environmental Technology (WET) Center.