PhD position Research into the thermal destruction efficiency of per- and polyfluoroalkyl substances (PFAS)

Per- and polyfluoroalkyl substances (PFAS), a broad family of  more than 10,000 synthetic compounds, have been produced since 1940 for their specific water and dirt-repellent properties and thermal inertia. Today, these synthetic compounds are ubiquitous in all kinds of consumer products and industrial processes. Due to careless management of these compounds and resulting waste streams, these chemicals end up in the environment and are ubiquitous today. Since various PFAS (e.g. PFOA, PFOS, PFNA, PFHxS) have been associated with health effects, limit values ??have been introduced for water, soil and food and there is increasing support for a complete ban of these chemicals [1]. Recent research has shown that the air is also an exposure route for humans as various waste streams containing PFAS are discharged directly towards the air. VITO developed sampling and analytical methods to quantify PFAS in air [2]. In addition, more and more research is being conducted into technologies for the storage and destruction of these chemicals as these “forever chemicals” are very difficult to break down[3],[4]. Thermal destruction, by pyrolysis or combustion, is a frequently used technique for the breakdown of PFAS-containing waste streams [4],[5], but the extent to which PFAS molecules are fully mineralized (converted from organic fluorine to inorganic fluorine) and the impacts from process parameters (temperature, residence time, mixing) and post-treatment techniques of the waste gases (active carbon, electrofilter, etc.) on the final PFAS emissions are not yet fully understood. This is due on the one hand to uncertainties in the characterization (sampling and analysis techniques) and on the other hand to recent insights that during this process so-called “products of incomplete combustion” or PICs are generated, residual products that are either PFAS themselves or can be recombined into PFAS (precursors). This doctoral research will therefore specifically focus on the mineralization efficiency of thermal destruction; in particular the impacts from process parameters (temperature, residence time, composition of the feed) on the pyrolysis and combustion efficiency of PFAS and after-treatment techniques of the waste gases (active carbon, electrofilter, etc.). The research will combine kinetic modeling based on quantum chemical calculations with experimental field measurements on full-scale installations and is part of an internationally rapidly developing research context of organic measurement methods (volatile, semi-volatile and particle-bound) and analytical techniques (LC-MS, GC-MS) and a relevant societal context, aiming at sustainable management of PFAS.

PhD supervision

The PhD fellowship is granted within the collaboration between the University of Ghent and VITO. The successful candidate will be supervised by Prof.  Kevin Van Geem (Univ. of Ghent) and co-promoted by Dr. Jelle Hofman and Prof. Stefan Voorspoels (VITO).

How to apply?
Applications should be submitted online and include a copy of your CV, diploma transcripts and a cover letter. 

More information about the application procedure is available on the VITO website. 

Overview of the jury’s scheduled in 2025 and deadlines: https://vito.be/en/jobs/phd/phd-jury

• Master in Chemistry, Pharmaceutical Sciences, Chemical Engineering or similar.

• Good oral and written communication skills in English.