Electrochemical cell tubular

Fig. 10. Flow-through electrochemical cell designs. I, Planar geometries, thin-layer (A) and wall-jet (B) flow cell designs. II, Cylindrical geometries, open tubular (A), wire in a capillary (B), and packed-bed (C) flow cell designs...

Flow cell Electrochemical cell in which analyte solution flows at a constant velocity Vf through stationary tubular electrode(s). 

Our interest in this chapter is with the mass and energy balances for chemical reactors, and in electrochemical cells. We consider first the mass and energy balances for tank and tubular reactors, and then for a general black-box chemical reactor, since these balance equations are an important application of the thermodynamic equations for reacting mixtures and the starting point for practical reactor design and analysis. Finally, we consider equilibrium and the energy balance for electrochemical systems such as batteries and fuel-cells, and the use of electrochemical cells for thermodynamic measurements. 

Figure 28. Left tubular reactor assembly and furnace used with bipolar cell configurations. 1 Pyrex tube (0=25/18 mm, length 400 mm, volume 150 mL) 2 electrochemical cell. Right bipolar electrochemical cells. A ring-shaped cell configuration B multiple-channel cell configuration.

Our studies turned from the methane coupling reaction to the investigation of higher temperature methane reactions. Using tubular electrocatalytic cells with Pt anodes, the conversion of methane becomes more selective with CO as the major product at high temperatures. As summarized in Table 6 methane conversions can approach 100% with CO selectivities up to 97% at 1100 C. This suggested that the electrochemical cells could be used for the partial oxidation of methane to synthesis gas. We call this process Electropox, for electrocatalytic partial oxidation. 

Figure4.5 The most common flow-through electrochemical cell configurations are as follows (A) thin-layer, (B) wall-jet, (C) tubular, (D) porous. The direction of fluid flow is...

Figure 7-24. Schematic representation of a membrane reactor operating with dense ionic conducting membranes for syngas production (a) tubular reactor using a MIEC membrane (b) Electrochemical cell using a purely ion conducting membrane.

Figure 6 shows a scheme of the sequential injection anodic stripping voltammetry system (SI-ASV) used for inorganic arsenic speciation in water samples. The system consisted of a MicroBu 2030 multisyringe burette with programmable speed (CS, Crison, Spain) used to aspire and dispense the reagent solutions, an eight-way selection valve (SV, Crison), a home-made tubular electrochemical cell (D), and a mixer chamber (MC). 

Fig. 6. Schematic set up of the SI-ASV flow system CS, carrier solution Rl, holding coil R2, reaction coil SV, selection valve R, reductant S, sample MC, mixer chamber D, detector W, waste. Components of the electrochemical cell a, reference electrode b, tubular gold electrode c, glassy carbon counter electrode d, connector, e, O-ring.

Singhal SC. Progress in tubular solid oxide fuel cell technology. In Singhal SC, Dokiya M, editors. Proceedings of the Sixth International Symposium on Solid Oxide Fuel cells (SOFC-VI), Pennington, NJ The Electrochemical Society, 1999 99(19) 39-51. 

S.C. Singhal, "Recent Progress in Tubular Solid Oxide Fuel Cell Technology," Proceedings of the Fifth International Symposium on Solid Oxide Fuel Cells (SOFC-V), The Electrochemical Society, Inc., Pennington, NJ, 1997. 

The active surface to volume ratio of the tubular arrangements previously described is approximately 1 cm2/l cm3. This parameter could be increased with corresponding increases in both volume power density and area power density. New concepts for solid state electrochemical reactors have been proposed based on more or less planar cell structures which can be integrated to make blocks. 

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