The Chair of “Resource Recovery from Wastewater” at RPTU Kaiserslautern-Landau is looking for a Ph.D. student to address a central challenge in phosphorus recovery from sewage sludge at wastewater treatment plants (WWTP): the interference of iron ions with struvite precipitation. Current methods to handle this through metal complexation with citric acid, which is costly and technically unstable. Your project focuses on the selective adsorptive removal/recovery of iron from acidified sewage sludge using zeolites. This process is intended to provide an iron-poor phosphate stream for struvite precipitation and represent a transfer of technology from mining wastewater treatment to phosphate-rich sludge matrices. You will be responsible for the scientific development of the project, which is structured in laboratory scale fundamentals and upscaling to pilot applications using fixed-bed reactors. Furthermore, Project D3 will broaden the scope of WERA beyond phosphorus to include a holistic view of recovering resources like metals, nitrogen, potassium, and water. In WERA you will work closely with other sub-projects, utilizing material expertise for zeolite characterization, process engineering inputs, modelling data, etc.
The most relevant scientific questions of your Ph.D. will be:
- How can the iron removal be optimized under acidic conditions to maximize Fe-binding while maintaining a high throughput of valuable nutrients (phosphate, ammonium, potassium)?
- How do matrix conditions (type and concentration of interfering ions) and the oxidation state of iron (Fe2+ vs. Fe3+) influence adsorption efficiency?
- How stable are the adsorbent materials over long-term operation, and what is the maximum number of loading and regeneration cycles achievable without significant performance loss?
Our requirement profile:
- Excellent M.Sc. in Engineering (Environmental, Process, Chemical), Natural Sciences or equivalent.
- Strong interest in wastewater treatment and adsorption.
- Willingness to work hands-on at both lab and pilot scales.
- Proficient English; German is desirable.
Please send your application (letter of motivation, CV, copies of Bachelor’s/Master’s certificates with complete lists of grades, any other relevant evidence) for this PhD topic to Asst. Prof. Dr. Carlo Morandi: carlo.morandi[at]rptu.de
