Microstructured reactors modeling

Cao, C., Wang, Y., and Rozmiarek, R.T. Heterogeneous reactor model for steam reforming of methane in a microchannel reactor with microstructured catalysts. Catalysis Today, 2005,110 (1—2), 92. 

Zanfir, M., Gavriilidis, A., Zapf, R., Hessel, V., Carbon dioxide absorption in a falling film microstructured reactor Experiments and modeling, Ind. Eng. Chem. Res. 44(6) (2005) 1742-1751. 

In this chapter, fluid-fluid flow patterns and mass transfer in microstructured devices are discussed. The first part is a brief discussion of conventionai fluid-fluid reactors with their advantages and disadvantages. Further, the ciassi-flcation of fluid-fluid microstructured reactors is presented. In order to obtain generic understanding of hydrodynamics, mass transfer, and chemical reaction, dimensionless parameters and design criteria are proposed. The conventional mass transfer models such as penetration and film theory as well as empirical correlations are then discussed. Finally, literature data on mass transfer efficiency at different flow regimes and proposed empirical correlations as well as important hydrodynamic design parameters are presented. 

Kashid, M.N., Renken, A., and Kiwi-Minsker, L. (2010) CFD modelling of liquid-liquid multiphase microstructured reactor slug flow generation. 

Figure 8.8 Mass transfer in dispersed phase microstructured reactors where gas solute diffuses through liquid toward solid surface, (a) Schematic representation, (b) Resistance model.

The supply of the production unit plays only a minor role within this impact category, and the supply of the peripheral equipment has almost no effect. The results of the GWP on the laboratory scale highlight the fact that the transfer of the model reaction from batch to continuous mode in a microstructured reactor leads to significant reductions in greenhouse gases. Therefore, the lifetime of the microscale set-up plays a subordinate role. Similar results were obtained for the majority of impact categories considered. 

Volume 1 covers fluid dynamics, modelling, mixing of one-phase and dispersed two-phase systems, heat and mass transfer. One chapter is concerned about purification and separation focusing on extraction, membrane technology, and capillary electrochromatography. This is rounded off by a description on microstructured reactors and their engineering/design for various applications. 

The amount of iodide formed given by [I3-] + [I2] is a measure for the quality of mixing. Based on the reaction kinetics and the characteristic reaction time 1 2. Commenge and Falk [14] calculated the formation of iodine as a function of the mixing time in microstructured reactors. For the theoretical predictions, the authors used the relatively simple interaction by exchange with the mean (I EM) model described by ViHermaux [10]. The results obtained for different experimental... 

The idea of using microstructured reactors for preparative oxidations with ozone was firstly picked up by Wada et ol. [33]. Ozonolysis reactions of triethyl phosphite (Figure 6.30a), octylamine (Figure 6.30b), and 1-decene with subsequent reductive treatment (Figure 6.30c) served as model reactions, which were all conducted in ethyl acetate as solvent. 

Yang, B., Yuschak, T, Mazanec, T, Tonkovich, A. L., and Perry, S. Multi-scale modeling of microstructured reactors for the oxidative dehydrogenation of ethane to ethylene. Chem. Eng. J. 135, S147-S152 (2008). 

T. D. Burchell. A Microstructurally Based Fracture Model for Nuclear Graphites. In Proc. IAEA Specialist s Meeting on Status of Graphite Development for Gas Cooled Reactors, Toki-Mura, Japan, Sept 1991, IAEA TECDOC No. 690, Pub. IAEA, Vienna, 1993, pp. 49 58. 

This division is very useful during model development and implementation. Differentiated emphasis should be placed on these modeling scales depending on the model objectives. For instance, detailed polymerization kinetics is important if the precise prediction of polyolefin microstructure is required. On the other hand, apparent kinetics suffices if the model s objective is to follow the evolution of particle fragmentation or to describe reactor residence time effects on polymerization. These ideas are detailed in the following sections. 

Olefin polymerization reactors will now be modeled using a bottom-up approach, from microscale to macroscale. In this section polymerization kinetic models will be introduced to describe polymerization rates and polymer microstructures, ignoring any phenomena that may take place in the mesoscale and macroscale. These models depend on the concentration of reagents and temperatures at the active site. As explained in the previous... 

Reaction modelling of a microstructured billing film reactor incorporating staggered herringbone structures using eddy diffusivity concepts. Chem. Eng. 227, 66. 

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