A study on the impact of design of robocasted hierarchical structured catalysts on mass and heat transport, applied to methanol-to-olefins conversion
19 February 2016
UAntwerp, Campus Drie Eiken, Promotiezaal Q0.02 - Universiteitsplein 1 - 2610 Antwerpen-Wilrijk
Organization / co-organization:
Faculty of Science
Vera Meynen & Lidia Protasova
PhD defence Jasper Lefevere - Faculty of Science
Present-day catalytic research focusses often on enhancing the economic and environmental properties of existing processes. In order to do so process intensification is implied, the energy-efficiency, activity, selectivity and stability of catalysts need to be improved. By replacing packed beds of catalyst pellets or powders by a structured catalyst, the performance of reactions that suffer from mass and heat transfer limitations can be significantly improved. However the architecture of the macroporous material will have an impact on the catalytic properties of the final catalyst.
In this work the use of 3D-printing for the manufacturing of new catalytic materials was investigated. The use of zeolite coated inert support materials as well as direct printing of a zeolite material was optimized for the use as catalyst in the methanol-to-olefins reaction (MTO). The goal of this work was to map the possible advantages and drawbacks of the use of such materials for catalysis and sorption.
The results discussed in this thesis imply that the high degree of freedom in the design and composition of the catalyst offers major improvements to the final catalytic properties. It was shown that catalysts with altered stacking of the layers of the material have improved stability and stability both in a coated and in a self-supporting catalyst system. The results of modeling confirms that the higher mixing efficiency and turbulence in the flow, with these kind of structures, lead to improved mass- and heat transfer properties. Furthermore, the impact of the binder(s) in the self-supporting catalyst structure was studied. By considering a binary combination of binders the mechanical strength as well as the catalytic properties of the final catalyst were improved.
Next to MTO, it was shown that other applications in both catalysis and sorption could benefit from this technology as the composition as well as the architecture of the active material could be optimized in function of the application.