Catalysts and Mechanisms
Within the research area „Catalysts and Mechanism“ for the synthesis of hydrocarbons from hydrogen and CO and/or CO2, the institute is targeting different research questions starting from catalyst level up to the consideration of entire process chains. In particular, catalysts for the Fischer-Tropsch-Synthesis as well as for the methanol resp. direct DME Synthesis are studied in operando/in situ using synchrotron light sources in cooperation with the Institute for Chemical Technology and Polymer Chemistry (ITCP) in order extract valuable suggestions for catalyst improvements from the results obtained. This also includes the arrangement of several catalysts in a reactor according to the principle of process integration.
In-situ XANES measurements during the reduction of a homemade Co-catalyst
In the case of the Fischer-Tropsch process line, combinations of RWGS and Fischer-Tropsch catalysts as well as combinations of FT and hydrocracking catalysts as powders and also as coatings are investigated. In the area of methanation, catalysts from type FeNi3 are investigated together with the KIT's ITCP. These investigations are accompanied by research within the framework of the Kopernikus project Power-to-X.
In case of the DME-synthesis, the thermodynamics of the upstream methanol synthesis is the limiting factor. To overcome this limitation, the single-stage DME synthesis in microstructured reactors is a promising concept: the rational combination of the both catalysts in one reactor allows to shift the MeOH synthesis equilibrium by its direct dehydration to DME which eventually leads to an enhanced COx-conversion and as a consequence to an enhanced process efficiency.
The focal point of the investigations is on the targeted synthesis of spherical and planar multifunctional catalyst systems. The preparative work covers the synthesis of nanoscopic methanol catalyst (e.g. Cu/ZnO/Al2O3) via flame spray pyrolysis as well as the transfer to a suitable spherical and planar form via spray drying (spherical) and ink-jet/screen printing (planar), respectively. Using theoretical models of the catalyst systems, simulation studies unravel relevant properties of the catalysts providing specific suggestions for the catalyst preparation. By implementing and validating these suggestion, the feedback-loop can be closed and both, models and synthesis can be further optimized.
The direct synthesis of DME from CO/H2-mixtures using different configurations of bifunctional catalysts is investigated within the frame of the DFG priority program 1570.The direct conversion of carbon dioxide/H2-mixtures to DME using rationally designed planar catalyst coatings in microstructured reactors is within the scope of a project funded by the Vector Stiftung.
Publications (since 2013)
T. L. Sheppard, S. W. T. Price, F. Benzi, S. Baier, M. Klumpp, R. Dittmeyer, W. Schwieger, J.-D. Grunwaldt, In situ Multimodal 3D Chemical Imaging of a Hierarchically-Structured Core@Shell Catalyst at Work, Journal of the American Chemical Society, 139, 2017, 7855-7863, 10.1021/jacs.7b02177
Wenjin Ding, Giulia Baracchini, Michael Klumpp, Wilhelm Schwieger, Roland Dittmeyer, Adsorption Device Based on a Langatate Crystal Microbalance for High Temperature High Pressure Gas Adsorption in Zeolite H-ZSM-5 Journal of Visualized Experiments 114 (2016), 10.3791/54413
Wenjin Ding, Michael Klumpp, Hui Li, Ulrich Schygulla, Peter Pfeifer, Wilhelm Schwieger, Katja Haas-Santo, and Roland Dittmeyer Investigation of High-Temperature and High-Pressure Gas Adsorption in Zeolite H-ZSM-5 via the Langatate Crystal Microbalance: CO2, H2O, Methanol, and Dimethyl Ether, The Journal of Physical Chemistry C, 2015, 119 (41), 23478-23485, 10.1021/acs.jpcc.5b06591
Wenjin Ding, Michael Klumpp, Seungcheol Lee, Stephanie Reuß, Shaeel A. Al-Thabaiti, Peter Pfeifer, Wilhelm Schwieger, Roland Dittmeyer, Simulation of One-Stage Dimethyl Ether Synthesis over a Core-Shell Catalyst, Chemie Ingenieur Technik, 87(6), 2015, 702-712, 10.1002/cite.201400157
Seungcheol Lee, Katja Schneider, Julia Schumann, Aswani K. Mogalicherla, Peter Pfeifer, Roland Dittmeyer, Effect of metal precursor on Cu/ZnO/Al 2 O 3 synthesized by flame spray pyrolysis for direct DME production Chemical Engineering Science, 138, 2015, 194-202, 10.1016/j.ces.2015.08.021
Wenjin Ding, Hui Li, Peter Pfeifer, Roland Dittmeyer, Crystallite-pore network model of transport and reaction of multicomponent gas mixtures in polycrystalline microporous media, Chemical Engineering Journal, Volume 254, 2014, 545-558, 10.1016/j.cej.2014.05.081
Aswani K. Mogalicherla, Seungcheol Lee, Peter Pfeifer, Roland Dittmeyer, Drop-on-demand inkjet printing of alumina nanoparticles in rectangular microchannels, Microfluid Nanofluid, 16, 2014, 655-666, 10.1007/s10404-013-1260-3
Seungcheol Lee, Tim Boeltken, Aswani K. Mogalicherla, Uta Gerhards, Peter Pfeifer, Roland Dittmeyer, Inkjet printing of porous nanoparticle-based catalyst layers in microchannel reactors,Applied Catalysis A: General, 467, 2013, 69-75, 10.1016/j.apcata.2013.07.002