Project title: Efficient removal of Nano-Plastics from water through enhanced coagulation
Topic background – The contamination of rivers, lakes and oceans by plastics is a well known and highly visible type of pollution. But even more problematic is that, over time and due to mechanical wear, these plastics can eventually degrade to extremely small particles. The resulting Nano-Plastics, in the size range of 1-1000 nm, behave as stable colloids allowing them to easily spread throughout the water system. Moreover, their small size allows their uptake and accumulation in aquatic life, but eventually also poses a risk to human health. New technologies are urgently required to address the problem of Nano-plastics and to effectively remove them from water.
Research challenges – The main challenge in removing Nano-Plastics stems from their small and varied size. Where the larger sized Nano-Plastics can still be removed through flocculation, the smallest Nano-Plastics would require technologies such as adsorption or membrane technology. While combining various technologies is a possibility, it would add significant extra costs to existing water treatment processes. It would be much more efficient to achieve an enhanced coagulation of the smallest Nano-Plastics, to bring them into a size range where easy removal becomes possible.
Objectives and methodology – In this project we will develop enhanced coagulation approaches to aggregate especially the smallest fraction of Nano-Plastics, thereby allowing their effective removal through standard flocculation and floatation approaches. Additives based on charged polymers and/or particles will be selected and/or developed to maximize the destabilization of Nano-Plastics, while these additives should themselves be bio-degradable and completely non-toxic. The approaches will initially be studied under well-defined lab scale conditions, but when successful they will be further tested at larger scales and with more complex mixtures of Nano-Plastics in typical surface or waste water conditions. In collaboration with the involved companies we will then translate obtained insights and technologies into the most efficient ways to integrate Nano-Plastic removal into established water treatment processes.
Students requirements: We are looking for a highly motivated candidate with a background (MSc) in colloid and interface science, physical chemistry, water technology or chemical engineering. The candidate will require a high level of independence and will need to be able to work from an interdisciplinary perspective.
Keywords Nano-Plastics, Water Treatment, Polyelectrolytes, Flocculation
Academic supervisors: Prof. Dr. Wiebe M. de Vos (University of Twente, Membrane Surface Science, Membrane Science and Technology Cluster) and Dr. Saskia Lindhoud (University of Twente, Molecular NanoFabrication, Department of Molecules and Materials)
Wetsus supervisor: Dr. Martijn Wagterveld
Only applications that are complete, in English, and submitted via the application webpage before the deadline, 9 May 2022 15:00 CEST, will be considered eligible.
Guidelines for applicants: https://phdpositionswetsus.eu/guide-for-applicants/.
The call is closed. Please be informed that we no longer accept applications for the current call. We thank you for your interest.