Designing Next-Generation Water Treatment Trains for PFAS and Micropollutant Removal?
Radical exposure allocation in sequential O3/H2O2–UV/H2O2–GAC treatment trains: implications for transformation products and carbon lifetime
This project addresses a growing societal need for safe, affordable and sustainable water treatment and water reuse. Organic micropollutants, transformation products and persistent compounds such as PFAS increasingly challenge conventional water treatment and public confidence in water quality. Utilities must therefore meet stricter expectations for health protection while limiting energy use, chemical consumption, and costs. One of the solutions to this problem is the use of sequential advanced oxidation processes and activated carbon filtration, as it can target a broad range of micropollutants including PFAS. Linking upstream oxidation choices to downstream GAC/BAC performance is relevant because activated carbon lifetime is under pressure by new compounds such as PFAS and strongly affects resource use, operational expenses and environmental footprint. The project will deliver practical design rules for robust treatment trains that improve micropollutant removal while limiting by-product formation. Results will support utilities, technology providers and regulators. The candidate will gain expertise in advanced water treatment and build a network across leading academic and industrial partners.
Research challenges
Current AOP–GAC/BAC practice still lacks a quantitative bridge between radical exposure, transformation-product formation, micropollutant removal and carbon performance. Research has mainly optimized individual barriers for parent-compound removal, whereas utilities need train-level rules that account for matrix scavenging, radical and direct ozone reactions, and adsorption competition. A key gap is how the micropollutant abatement, by-product formation and GAC reactivation time depends on exposure of radicals (OH•) or ozone. This will be water matrix dependent (e.g. organic matter). In this project, we will explore how these exposures (OH• radical and ozone) affect organic micropollutant removal and by-product formation using lab-scale experiments, non-target analyses and models. In addition, the changes in organic matter content of the matrix will be investigated for the PFAS adsorption in a downstream GAC process. The project will generate new knowledge on the interaction between oxidation and adsorption processes. The candidate will gain expertise in advanced oxidation, adsorption, non-target analysis and modelling, while interacting with leading academic and industrial partners.
Your assignment
You will work in a collaborative environment involving ICRA, Wetsus, KWR and industrial partners including PWN, Trojan and Brown & Caldwell, ensuring strong exposure to real-world water treatment challenges. You will develop an exposure-based framework for designing sequential O3/H2O2–UV/H2O2–GAC treatment trains. The aim is to understand how the magnitude and allocation of hydroxyl radical and ozone exposure affect micropollutant removal, transformation-product formation, and downstream carbon lifetime. This will result in an exposure model. You will investigate two representative water matrices (surface water and/or waste water) and compare different dose-splitting strategies between ozone- and UV-based AOP steps at comparable micropollutant removal. You will quantify radical exposure using probe or internal compounds, UV fluence and ozone exposure metrics, and relate these to target micropollutant analysis and LC-HRMS non-target screening, providing training in advanced analytical techniques that are highly valued in environmental research and industry. You will then study how partially oxidized water affects GAC adsorption of and breakthrough of PFAS in batch and small-scale column experiments. Finally, you will translate the results into practical design and operational rules for partners.
Your profile
You will have a master’s degree in environmental engineering, chemical engineering, water technology, chemistry or a related field, with a strong interest in advanced water treatment. You will bring experience or clear affinity with laboratory experimentation, analytical chemistry, adsorption/oxidation processes, data analysis and modelling. You will be accurate, independent and collaborative, with good scientific writing skills and motivation to work with academic and industrial partners. Upon being selected, you will have opportunities to publish in leading peer-reviewed journals and present results at international conferences.
Keywords: Advanced oxidation processes; GAC filtration; PFAS removal; transformation products; radical exposure.
Professor/University group/Wetsus supervisor(s): University promotor and co-promotor: prof. dr. W. Gernjak (Girona University, ICRA); Wetsus supervisor(s): dr. ir. B.A. Wols (Wetsus / KWR)
Project partners: https://www.wetsus.nl/research-themes/advanced-water-treatment/
Only applications that are complete, in English, and submitted via the application webpage before the deadline will be considered eligible.
Guidelines for applicants: https://phdpositionswetsus.eu/guide-for-applicants
