Behaviour of a tall vertical gas-evolving cell. Part I: Distribution of void fraction and of ohmic resistance

Janssen, Ljj Jos; Visser, GJ

doi:10.1007/bf01024573

Cited by 16 publications

(16 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The ohmic resistivity of the solution between the anode and the cathode during current flow increases continuously with increasing height in the electrolyser when the bubble-liquid mixture can be characterized by a bubbly flow [2]. Furthermore, the resistivity of the solution between the electrodes at the leading edge of both the electrodes increases practically linearly with the local current density, but the increase in solution resistivity at the bottom of the cell is larger than at the top of cell.…”

Section: Introductionmentioning

confidence: 82%

“…The determination of ex,h is extensively described in [2]. In practice, the effect of the non-uniform distribution of current has to be taken into account to calculate the voidage distribution in a gas-evolving cell.…”

Section: Discussionmentioning

confidence: 99%

“…4 from [2]) and 7p = 0.4464 x 10-4f~m 2 (calculated from Rp,20 = 0.186f~ and A~ = 2.4 x 10 4m2 [2]), 7b at various i~v has been calculated. The results are provided in Table 1.…”

Section: Discussionmentioning

confidence: 99%

“…Unless otherwise mentioned GEEST-2 was used. The relations between the current density, the cell voltage and the ohmic potential drop over the solution between the segments of a pair were determined with a Solatron 1250 frequency response analyser and a Solatron Electrochemical Interface 1286, as described in [2].…”

Section: Electrical Measurementsmentioning

confidence: 99%

“…Results on cell impedance are published separately [2] and those on current distribution are presented in this paper.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Behaviour of a tall vertical gas-evolving cell Part II: Distribution of current

Janssen

Visser

1991

J Appl Electrochem

Self Cite

View full text Add to dashboard Cite

Vertical electrolysers with a narrow electrode gap are used to produce gases, for example, chlorine, hydrogen and oxygen. The gas voidage in the solution increases with increasing height in the electrolyser and consequently the current density is expected to decrease with increasing height. Current distribution experiments were carried out in an undivided cell with two electrodes each consisting of 20 equal segments or with a segmented electrode and a one-plate electrode. It was found that for a bubbly flow the current density decreases linearly with increasing height in the cell. The current distribution factor increases with increasing average current density, decreasing volumetric flow rate of liquid and decreasing distance between the anode and the cathode. Moreover, it is concluded that the change in the electrode surface area remaining free of bubbles with increasing height has practically no effect on the current distribution factor. Notation iav

show abstract

Section: Introductionmentioning

confidence: 82%

Section: Discussionmentioning

confidence: 99%

“…4 from [2]) and 7p = 0.4464 x 10-4f~m 2 (calculated from Rp,20 = 0.186f~ and A~ = 2.4 x 10 4m2 [2]), 7b at various i~v has been calculated. The results are provided in Table 1.…”

Section: Discussionmentioning

confidence: 99%

Section: Electrical Measurementsmentioning

confidence: 99%

“…Results on cell impedance are published separately [2] and those on current distribution are presented in this paper.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Behaviour of a tall vertical gas-evolving cell Part II: Distribution of current

Janssen

Visser

1991

J Appl Electrochem

Self Cite

View full text Add to dashboard Cite

show abstract

Electrochemical Reactors

Vogt¹,

Kreysa²

2008

Ullmann's Encyclopedia of Industrial Chemistry

View full text Add to dashboard Cite

The article contains sections titled: 1. Reactors with Gas‐Evolving Electrodes 1.1. Effects of Gas Evolution on Cell Operation 1.2. Bubble Nucleation, Growth, and Detachment 1.3. Bubble Coverage 1.4. Product Release 1.5. Ohmic Resistance of the Interelectrode Gap 1.6. Mass Transfer at Gas‐Evolving Electrodes 1.7. Heat Transfer 1.8. Overpotential of Gas‐Evolving Electrodes 1.9. Limiting Current Density at Gas‐Evolving Electrodes 1.10. Electrodes 1.11. Gas‐Lift Systems 2. Reactors with Superficial Electrodes 3. Reactors with Three‐Dimensional Electrodes 4. Special Reactor Designs The operating modes of electrochemical reactors vary as widely as the designs of the reactors. This is determined not only by the chemical behavior of the different electrolytes, especially their corrosivity, but also by the very different products. These can be formed as solids, as in electrodeposition, in liquid form, as in the case of many substances that react further in the liquid phase, or as a gaseous phase, for example, in the electrolysis of water. Operating temperatures cover a wide range, from room temperature to 1000 °C. In most cases the electrolytes are liquid solutions or melts, but more recently also solids (e.g., solid polymer electrolytes) and in special cases gases, as in high‐temperature water electrolysis, or plasmas in glow‐discharge electrolysis. Accordingly, the materials and shapes of the electrodes also very diverse. The simplest electrodes are those with flat surfaces. Two such electrodes face each other a few millimeters apart in order to minimize the ohmic potential drop across the gap, or they are divided by a liquid‐permeable diaphragm or gas‐permeable membrane, which also separates the electrolyte chambers from one another. In many cases specially shaped electrodes are used that better meet the requirements of a process. Their influence on the design and operation of the reactors are the subject of this article. In particular, these are reactors with gas‐evolving electrodes and special reactor designs to meet specific requirements.

show abstract