Electrochemical reactors, cross-flow

J.N. Michaels, C.G. Vayenas, and L.L. Hegedus, A Novel Cross-Flow Design for Solid State Electrochemical Reactors, J. Electrochem. Soc. 133, 522-525 (1986). 

Vayenas C.G., Debenedetti P.G., Yentekakis Y., Hegedus L.L. (1985) Cross-flow solid-state electrochemical reactors A steady-state analysis. Industrial Engineering Chemistry Fundamentals 24, 316-324. 

Mathematical Modeling of Cross-Flow, Solid State Electrochemical Reactors... 

Cross-Flow Solid State Electrochemical Reactors 173... 

Consideration of diffusional and kinetic limitations, when justified by physical reality, may yield additional information on the behaviour of cross flow monolithic electrochemical reactors. A balance between added numerical complexity and a more complete description of electrode kinetics, should, of course, be kept in mind. 

A transfer of this definition of the cross-flow term to the chemical reactor field implies that the so-called cell reactor [26], consisting of thin, porous catalyst plates mounted in a rack like a filter press, should also be of interest to describe here. The same may apply to the great number of different electrochemical filter-press cell reactors [27]. It may be noted that the cell reactor principle is, however, not valid for the so-called parallel-passage reactor [28,29]. In this case the same fluid flows on both sides of the catalyst plates without any need for communication and exchange between the fluids through the plates. The advantage of this reactor is its being dust-proof, since dust present... 

The three kinds of reactors already described in this section are all traditional cross-flow reactors with permeable plates or membranes. The electrochemical filter-press cell reactors used, e.g., for electrosynthesis, are equipped with cation-selective membranes to prevent mixing of the anolyte and the catholyte. These cell reactors are therefore good examples of the extended type of cross-flow reactors according to the definition transferred from the filtration field. The application of the electrochemical filter-press cell reactor technique... 

The catalytic plates are not completely accessible in the monolithic cross-flow structure, since a certain part of the plates is lost by contact with the corrugated interstitial planes of this structure. Moreover, the successful development in the preparation of thin, porous plates for electrochemical purposes created the idea that this preparation technique should also be used to produce permeable catalyst plates for cross-flow catalyst reactors. Instead of using these plates for the complicated cross-flow structure, the whole step was taken to using them in an electrochemical cell-like design of the reactor. The catalytic plates were thus mounted in a special rack like a filter press (Fig. 13), giving the so-called cell reactor [26]. 

In mathematical modeling of cross-flow solid-state electrochemical reactors, the dimension of the mathematical model increases with two additional variables compared to gas-liquid processes, since both the heat balance and the electron balance have to be considered. Introduction of an integral electron conservation balance results in an integro-differential problem. A comprehensive study of this kind was performed by Vayenas et al. [48] and by Debenedetti and Vayenas [49]. 

C.G. Vayenas, P.G. Debenedetti, 1. Yentekakis, and L.L. Hegedus, Cross-flow, solid-state electrochemical reactors A steady-state analysis, Ind, Eng. Chem. Fundam. 24 316 (1985). 

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