Ph.D. Moritz Weiß

  • KIT - Campus Süd
    Institute of Mechanical Engineering and Mechanics
    Applied Mechanics Group
    Gotthard-Franz-Straße 3, Geb. 50.31
    76131 Karlsruhe

Catalytic membrane reactors from capillary suspensions

Porous membranes are used as catalysts for selective extraction of single components, controlled dosing of a reactant, and to intensify the contact between reactants to increase the reaction rate. The manufacture of these catalytic membrane reactors faces several challenges including the preservation of a very high surface area while ensuring mechanical stability. Depending on the application, a specific pore size, permeability, or hierarchical structure may also be desired.

Capillary suspensions are three-phase systems with a small amount (< 5 vol%) of an immiscible secondary phase added to a suspension. The secondary phase creates a strong sample spanning network due to capillary forces, which changes the material strength from fluid-like or weakly elastic to strong gel behavior. The particle network connected through capillary bridges does not collapse during debinding or sintering, and thus can serve as precursor for sintered materials with high open porosity. This process will be adapted to use highly porous, catalytically active particles. The secondary fluid has to be wisely chosen and an innovative sintering strategy has to be developed in order to avoid reduction of the total surface area or damage the surface chemistry of active particles. The aim is to create chemically activated sintered bodies for catalysis. Therefore, the bodies are formed through a 3D printing or extrusion process to achieve hierarchically structured highly porous green bodies with complex shapes.

 

Publications

  1. Monica Schneier, Johannes Maurath, Steffen Fischer, Moritz Weiß, Norbert Willenbacher, Erin Koos
    Suppressing Crack Formation in Particulate Systems by Utilizing Capillary Forces
    ACS Applied Materials and Interfaces, 2017
    https://pubs.acs.org/doi/abs/10.1021/acsami.6b13624
  2. Irene Natalia, Nicole Zeiler, Moritz Weiß, Erin Koos
    Negative normal stress differences N1-N2 in a low concentration capillary suspension
    Soft Matter, 2018
    https://pubs.rsc.org/en/Content/ArticleLanding/2018/SM/C8SM00305J#!divAbstract
  3. Moritz Weiß, Johannes Maurath, Norbert Willenbacher, Erin Koos
    Shrinakge and dimensional accuracy of porous ceramics derived from capillary suspensions
    Journal of European Ceramic Society 2019
    https://www.sciencedirect.com/science/article/abs/pii/S0955221919300111

Presentations

  1. Johannes Maurath, Moritz Weiß, Benjamino R. Formisano, Christian Bonten, Erin Koos
    Extrusion of Porous Ceramics from Capillary Suspension (Poster)
    91. DKG Jahrestagung, March 07-09 2016, Freiberg, Germany
  2. Moritz Weiß, Erin Koos
    Tuning cermic microstructures using capillary suspensions with incorporated nanoparticles (Talk)
    91. 15th European Ceramic Society, July 09-13 2017, Budapest, Hungary