Benjamin Bursik from the Institute of Technical Thermodynamics and Thermal Process Engineering of the University of Stuttgart is a SFB 1313 doctoral researcher (research project A01) and a member of the SFB 1313 Integrated Research Training Group "Interface-Driven Multi-Field Processes in Porous Media". He visited the University of Campinas (UNICAMP), Brazil, from January to April 2025.
Research Report
From January to April 2025, I had the opportunity to conduct a research stay at the University of Campinas (UNICAMP), Brazil, hosted by Prof. Luís Franco. My research focused on improving process models for CO₂ adsorption in porous media. Adsorption processes are important in technologies such as carbon capture and storage as well as direct air capture, which play a crucial role in reducing greenhouse gas emissions and combating climate change.
Traditional process models for CO₂ adsorption often rely on macroscopic assumptions and extensive experimental data, which limits their predictivity. The goal of this project was to integrate molecular-level information into these process models to make process models more accurate and predictive. To achieve this, we combined process models with molecular thermodynamic models such as the SAFT-VR-Mie equations of state, as well as classical density functional theory (DFT). These molecular models allow us to describe adsorption isotherms and transport properties in confined systems and reduce the need for experimental data.
During my stay, I first implemented a simplified equilibrium process model and systematically evaluated how well different molecular models predict adsorption behavior. Beyond these equilibrium studies, we worked on more advanced models by implementing a dynamic, one-dimensional model for a temperature swing adsorption process. We focused on CALF-20, a particularly promising metal organic framework for CO₂ adsorption. In particular, we included adsorption isotherms from the confined version of SAFT-VR-Mie and DFT. By comparing results to experimental data from literature for a CO₂+N₂ mixture, we found that the molecular model achieves similar accuracy with significantly less experimental information. These developments lay the foundation for future work, where we plan to study the influence of water on the adsorption process, which presents a significant challenge to state-of-the-art models.
Beyond the scientific work, my stay in Campinas was personally enriching and unforgettable. The extremely welcoming atmosphere in Prof. Luís Franco’s group made it easy to collaborate, exchange ideas, and to make new friends. Outside the lab, I had the chance to explore Brazilian culture, which includes playing football, Brazilian barbecues, and, of course, carnival. A special thank you goes to Nikolas de Souza, André Gonçalves, Arthur Weidmann, Felipe Coelho and Estefânia Canzian, whose support and friendship truly exceeded all my expectations. I am deeply grateful to Prof. Franco and his entire group for their hospitality, inspiring discussions, and for making my time in Brazil a memorable and rewarding experience.
