Membrane processes play a vital role in water treatment. Today they are widely used in drinking water treatment, seawater desalination and the food industry among other applications. Although they allow for more energy- and resource-efficient operation than conventional large-scale industrial processes, producing polymer membranes still presents challenges for a sustainable industry. This is due to the usage of polymers from petroleum sources and of toxic organic solvents such as NMP or DMF, which are harmful to the environment and humans.

In our working group, we are addressing this problem by producing membranes using the environmentally friendly SIPS (salt-induced phase separation) process, which utilizes water as a solvent. To do this, we use polyelectrolytes, i.e. polymers whose repeating units contain electrolytes. If two oppositely charged polyelectrolytes are dissolved in an aqueous solution with a high concentration of an added salt, a viscous mass is formed from which membranes can be fabricated.

The aim of the project is to further develop the SIPS process by replacing oil-based starting materials with bio-based polyelectrolytes, such as chitosan or lignosulfonates. This work will focus on screening different polyelectrolyte combinations to find a suitable solution for membrane fabrication. The scope of the work package can be adjusted according to the respective work (MA, BA, internship...). The work can be carried out in either in German or English and the start time can be chosen flexibly.

Tasks:

• Preparation of polyelectrolyte solutions

• Polymer analyses (e.g. viscosity)

• Flatsheet membrane fabrication

• Membrane characterization (e.g. PWP, MWCO, zeta-Potential)

Your Profile:

• Enrolled in Chemistry, Water Science, Process Engineering, or similar subjects
• Interested in membrane fabrication
• Good communication skills

Supervisor(s):

• Rik Mittelstedt, M.Sc.

Are you interested in this topic and do you want to play an active role in the fabrication of new sustainable membranes? Then don’t hesitate to write me an e-mail (rik.mittelstedt[at]uni-due.de) or come visit me in my office.