Control and intensification of chemical reactions due to periodically operating distributors

• Applicants: Professor Dr.-Ing. Christof Hamel; Professor Dr.-Ing. Andreas Seidel-Morgenstern
• Subject Area: Chemical and Thermal Process Engineering
• Term: from 2017 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 382737264

Aim of the project is to increase the yield of desired olefins by means of reactant dosing in membrane distributors. In a periodically operating distributor the oxidative and thermal dehydrogenation of the industrial relevant model system propane should be investigated. With a view to exploiting maximum synergy effects a mass and energy coupling in one integrated reactor will be realized and evaluated.The disadvantage of catalyst deactivation in the thermal dehydrogenation is intended to be compensated by a periodically operation exploiting the apparatus/catalyst in each phase of the process. Thus, a controlled transmembrane oxygen flow, changing temporally with catalyst activity, has to be estimated based on suitable models. Control of temperature and velocity of reaction fronts will be efficiently adjusted by distributed dosing.Based on transient computational studies (1D/2D) optimal dosing profiles were identified by characterising and evaluating the complex temperature and velocity fields. Furthermore, the deactivation/regeneration of the catalyst by using thermogravimetry and a segmented fixed-bed reactor in a laboratory scale was quantified and mathematically described. Detailed 2D models implementing various approaches for heat transfer were applied to study the influence of particle diameter and porosity distribution by dosing concepts in membrane reactors in order to evaluated the planned reactor scale up.The temporal development of the project was influenced by unforeseeable factors (Preamble) e.g. the Corona shutdown of the mechanical workshop and the pilot plant hall. Thus, the important experimental based working packages 4-5 are not in progress yet. These APs aim in particular at the planned realization of the developed periodically operated distributors not only in a disintegrated (decoupled temperature effects) but also in a fully integrated way with material and energetic coupling in pilot scale They play an essential role for the successful overall conclusion of the project in the form of the experimental validation of the promising simulation results obtained so far on a pilot scale. Up to now, during the successful course of the project, 9 contributions to national and international conferences (1 poster price) and a first paper „Analysis of Membrane Reactors for Integrated Coupling of Oxidative and Thermal Dehydrogenation of Propane” (2 further publications in preparation) could be published.

• DFG Programme: Research Grants