Topic background

In these times where accessibility to safe drinking and irrigation water is becoming increasingly important, (membrane)adsorption is a versatile technology for the selective removal of undesired components or the capturing of valuable resources for reuse to attack water scarcity. Currently there is an increasing strong concern about the presence of fluoride containing compounds in ground and surface water because of their persistence and associated health effects. PFAS present in water bodies and threatening the quality of our drinking water urgently has to be removed from the environment. A highly flexible approach for the selective capturing of components from aqueous streams are polymer membrane adsorbers: hierarchical porous structures, often post-modified to introduce dedicated functionalities that rely on e.g. electrostatic and hydrophobic interactions or affinity. As such, membrane adsorber technology offers a platform for the capturing of undesired components as well as the recovery of valuable resources for reuse and recycling.

Research challenges
Development of a selective membrane adsorber platform to capture selectively components such as PFAS requires: (1) The use of green and sustainable materials: green solvents, (biobased)polymers, functional organic and inorganic additives to enhance affinity and selective adsorption. (2) Control over functionality, specificity, stability and tuning of porosity, pore size and pore size distribution is critical to set the ultimate separation performance, the throughput, flow rates, concentrations, etc. (3) Assembling of developed structures into modules is a challenge, but essential such that ultimately also large-scale applications are within reach.

The proposed approach is centered around electrospinning: a very versatile technology offering the possibility to produce nanofibers together forming very open, highly porous, robust polymer structures with a low flow resistance. When functionalized such hierarchical porous structures are able to selectively bind specific components for e.g. direct capturing of unwanted components or recycle and reuse.

Your assignment
The aim of this research is the development of green platform for membrane development using electrospinning of polymers with intrinsic functionality or co-electrospinning of polymers and functional particles to prepare engineered porous hierarchical structures with tunable properties for specific separations.

You will explore different polymers and green solvents for electrospinning and you will develop porous membranes focussing on morphological (functionality, porosity, pore size) and performance (capacity, selectivity, adsorption-regeneration cyclability) characteristics. The functionalized electrospun mats will be stacked or wrapped into adsorption modules for performance evaluation. Target impurity is PFAS. Characterization methods like SEM, pore size and porosity characterization, BET, TOC, IC, ICP, HPLC, streaming potential, contact angle, permeation equipment, static and dynamic cyclic adsorption-regeneration will be used.

You will benefit both from the scientific knowledge from Wetsus and Eindhoven University of Technology as well as the expertise from the participating industrial theme members.

Supervisory team: Prof. dr. ir. Kitty Nijmeijer (Eindhoven University of Technology), Dr. Zandrie Borneman (Eindhoven University of Technology), Jan Post (Wetsus)

Project partners: Theme consortium around PFAS