Parallel plate filter press cells

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 importance of high rates of mass transport for a clean and efficient electrosynthesis using a filter press reactor has been stressed, and the effect of inclusion of a platic mesh turbulence promoter considered [56]. A multipurpose filterpress cell for continuous electrolysis of organic compounds has been described [57], and a mathematical model of the startup of a continuous parallel-plate reactor has been published [58]. 

Parallel-plate flow cells Most electrochemical flow cells are based on a parallel-plate electrode design with either horizontal or, more commonly, vertical electrodes in a monopolar or bipolar configuration (see Figure 26.12). With vertical electrodes, the cell is usually constructed in a plate-and-frame arrangement and mounted on a filter press. 

In either version, cells of the bipolar type assembled to batteries of the filter-press t5q)e can be used. The version with circulating electrolyte is also feasible for building monopolar ( jai -type) cells that are cheaper than bipolar types (as they do not require expensive bipolar plates) and offer a highly flexible series-parallel switching within the battery to accommodate specific user needs. 

With vertical electrodes the cell is usually constructed in a plate-and-frame arrangement and mounted on a filter press. The electrodes, electrolyte chambers, insulating plates to separate cells electrically and, where used, membranes or separators are constructed individually and mounted with suitable gasketing materials between each component the filter press is then used to seal the cells with up to 100 cells in each unit (see Fig. 2.14). It is difficult to manufacture the cells with an area greater than 1 m. Again the electrical connection may be bipolar instead of monopolar (effectively by removing the intercell insulation) and in a series of cells the electrolyte feeds to the cells may be connected so that the cells are in series or parallel so far as the electrolyte is concerned. 

The parallel plate geometry [1,3] offers uniform current density and potential distribution. The incorporation of this electrode geometry into a plate and frame cell body, particularly in a modular filter-press format, provides a versatile workhorse for many electrochemical reactors. Many developments start with a small, single cell before being scaled-up by increasing the electrode area and then by designing a multiple cell stack in a filter press stmcture. Parallel plate cells have many advantages ... 

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