Microscopic particle interactions in surface filtration processes (MicSurF)

• Applicant: Professor Dr.-Ing. John Linkhorst
• Subject Area: Chemical and Thermal Process Engineering
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 514031987

In surface filtration processes the filtrated particles accumulate on the membrane surface, increase the hydraulic resistance, and reduce the overall process performance. The conventional pressure-flux analysis lacks of insights into the cake morphology and the impact of particle characteristics on the cake. In this project we will study the influence of particle properties on the filter cake morphology and the hydrodynamic filtration resistance using microfluidic in-situ visualization techniques. First, 3D-particles with desired 3D-shape, size-distribution, porosity, and softness are fabricated using microfluidic stop flow lithography and continuous two-photon polymerization. Second, these particles are filtered with membrane-mimicking microfluidic cell and the filter cake will be analyzed using in-situ high resolution confocal microscopy. A precise module design with well controlled system parameters will allow visualization and analysis of single particles and their interactions. Third, based on the microscopic observations, we will validate the microscopic phenomena in a lab scale filtration cell and analyze their influence on relevant process conditions, such as cake built up and cake removal. The investigation of filter-cakes in the lab scale filtration cell lacks in resolution during visualization, but comprises real process conditions with realistic cross-flow flow fields and commercial membranes. This project will give a fundamental micro-scale understanding of filter cakes in surface filtration processes. It will bridge the gap between microscopic particle properties and empirical membrane performance. The results will contribute to improve accuracy of mathematical filtration models which are based on physical properties of the filtration system.

• DFG Programme: Research Grants