With the increasing demand for alternative fuels the storage of natural gas (NG) in adsorbents like metal organic frameworks (MOFs) will become more important. In order to use MOFs as storage media in fuel delivery systems, the optimization of mass and energy transfer of the system is crucial. For rapid NG filling of a tank, molecules need to reach the adsorption sites within a reasonable time while the heat of adsorption should be dissipated to the environment. In this article, mass transfer in shaped bodies of MOFs was determined by permeability measurements and pulsed field gradient (PFG) NMR spectroscopy. The heat dissipation was also experimentally measured and both data sets were used to set up a theoretical density function theory model to predict the behavior of MOFs for NG storage.

Deactivation of catalytic processes such as direct oxidation of hydrogen sulfide by coking through hydrocarbon combustion has always been a topic of concern. Using n-hexane as a model compound, we develop a kinetic model that predicts its coking rate on the basis of data obtained from a thermobalance. Considering two different processes in the coke reaction, active site coverage and coke growth, and applying a probabilistic model, we obtain an apparent activation energy of 34 and 126 kJ/mol, respectively. Thus, we estimate pore-plugging effects using two network models: a bundle of parallel cylindrical pores using a probabilistic model and a microporous network distributed in a Bethe lattice. Both models describe experimental data. Moreover, they confirm that the TiO 2 catalyst used first deactivates through active sites coverage and second through pore obstruction. As such, the model may be used for estimating deactivation of reactions taking place simultaneously on the catalyst.

Der Quellcode eines solchen Open SourceProzesssimulators muss ein schon vorhandenes Programm sein, da Neuentwicklungen nicht finanzierbar sind. Die Codes der kommerziellen Anbieter scheiden aus, anderweitig sind aber Entwicklungen verfügbar. Die Open Source-Prozesssimulation bietet eine Chance, eine nachhaltige und dynamische Weiterentwicklung der verfahrenstechnischen Simulationswerkzeuge zu erreichen, wie sie von einzelnen aus eigener Kraft nicht zu leisten wäre.

A model is proposed to investigate the deactivation through coke formation by accounting for active surface coverage and pore blockage under nonisothermal conditions in a two-dimensional pore network. The system is governed by the Thiele modulus, the Prater number, and the activation energies of the reactions involved. Two simple reactive paths are considered for the simulations, showing that the activity's prediction can differ strongly from the isothermal case both over time and with its coke content.