PhD topic of project B1: Thermodynamic modeling of the recovery of phosphorus from wastewater 

Thermodynamic modeling is the foundation for developing processes to recover valuable substances from wastewater, and understanding the thermodynamic properties of the mixtures and their components is a prerequisite for designing new processes or optimizing existing ones. However, the thermodynamic modeling of complex multi-component mixtures, such as wastewater, is challenging. 

This project aims to develop thermodynamic models to describe complex mixtures containing both molecular substances and electrolytes as they occur in wastewater treatment processes. A particular focus will be on simulating processes for phosphorus recovery from wastewater via adsorption and crystallization. For this purpose, novel predictive thermodynamic models for electrolyte solutions will be developed by combining classical physical models with data-driven algorithms from machine learning to yield powerful hybrid models. Furthermore, the question of how to deal with uncertainties, e.g., regarding incomplete knowledge of the composition of the mixtures, will be addressed.

 
The most important scientific questions of this PhD will be:

• What are the relevant phase equilibria of different phosphorus compounds in wastewater?
• How can the influence of the composition, pH value, and temperature be modeled?
• How can physical and machine-learning models be combined into hybrid models?
• How can analytical fingerprints from different measurement methods be used to model wastewater despite poor specification?
• How can separation processes be simulated based on hybrid models and incomplete information?

 
Requirements for applicants:

• Excellent Master’s degree (M.Sc.) or equivalent in chemical engineering or related fields
• Strong background in engineering thermodynamics, in particular, in measuring and modeling thermodynamic properties of mixtures, desirable
• Proficient in the English language and willing to learn German (for non-German speaking persons)  

 
Please send your application for this PhD topic to: fabian.jirasek[at]rptu.de 

Application:

Please send by 31.01.2026 complete application documents:

• Letter of motivation that prioritizes one of the PhD topics of WERA
• Curriculum Vitae
• Copy of your degree certificate (Bachelor, Master or equivalent) with full academic transcripts

directly to the supervisors of PhD topics (contact see rptu.de/wera/team). You can contact the spokesperson Prof. Sergiy Antonyuk (sergiy.antonyuk[at]mv.rptu.de) for general questions about PhD Graduate School.

Prerequisite for the PhD position is an Master’s degree (or equivalent) in engineering, chemistry or physics.

About RPTU University Kaiserslautern-Landau: 

The RPTU University Kaiserslautern-Landau is the technical university of the federal state of Rhineland-Palatinate with over 20,000 students, more than 300 professors and around 160 degree programmes. As a place of top-level international research, it offers excellent working conditions and career opportunities. Those who study, research or work at RPTU experience a welcoming and globally-oriented environment and shape the future.

The PhD Graduate School GRK 2908 is supported financially by the German Research Foundation (DFG) with funds from the German states and the federal government of Germany.