Journal of Applied Electrochemistry

, Volume 17, Issue 1, pp 67–76 | Cite as

Current distribution in a two-dimensional narrow gap cell composed of a gas evolving electrode with an open part

  • Yoshinori Nishiki
  • Koichi Aoki
  • Koichi Tokuda
  • Hiroaki Matsuda
Papers

Abstract

On the basis of the observation of gas bubbles evolved by electrolysis, a two-dimensional vertical model cell composed of electrodes with open parts for releasing gas bubbles to the back side is proposed. The model cell consists of two layers. One layer forms a bubble curtain with a maximum volume fraction of gas bubbles in the vicinity of the working electrode with open parts. The other. being located out of the bubble layer, is a convection layer with a small volume fraction distributed in the vertical direction under forced convection conditions. The cell resistance and the current distribution were computed by the finite element method when resistivity in the back side varied in the vertical direction along the cell. The following three cases for overpotential were considered: no overpotential, overpotential of the linear type and overpotential of the Butler-Volmer type. It was found that the cell resistance was determined not only by the interelectrode gap but also by the percentage of open area and in some cases by the superficial surface area. The cell resistance varied only slightly with the distribution of the bubble layer in the back side.

Keywords

Finite Element Method Cell Resistance Current Distribution Force Convection Back Side 

Nomenclature

b

linear overpotential coefficient given byb=η/i

C

proportionality constant given by Equation 15

d1

distance between front side of working electrode and separator

d2

thickness of separator

F

Faraday constant

I

total current per half pitch

i

current density at working electrode

i0

exchange current density

L

length of a real electrolysis cell

n

number of electrons transferred in electrode reaction

Op

percentage of open area given by Equation 1

p

pitch, i.e. twice the length of the unit cell, defined by 2(BC) in Fig. 4

q

thickness of bubble curtain, defined by (AM) in Fig. 4

R

gas constant

rt

total cell resistance

r

unit-cell resistance defined by (V − Veq)/I

rrs

residue ofr from sum ofr0 andrη

r0

ohmic resistance of solution when0p=0

rη

resistance due to overpotential when0p=0

s

electrode surface ratio or superficial surface area given by Equation 2 for the present model

T

absolute temperature

t

thickness of working electrode defined by EF in Fig. 4

V

cell voltage

Veq

open circuit potential difference between working and counter electrodes

ν

solution velocity in cell

ν0

solution velocity at bottom of cell

w

width of working electrode, defined by 2(DE) in Fig. 4

x

abscissa located on cell model

y

ordinate located on cell model

α

anodic transfer coefficient

β

linear overpotential kinetic parameter defined byb/[ϱbc(p/2)]

infinitesimally small length on the boundary

ε

volume fraction of gas bubbles in cell

ζ

dimensionless cell voltage defined bynF(V − Veq)/RT

η

overpotential at working electrode

Λ

Butler-Volmer overpotential kinetic parameter defined by [nFi0ϱbc(p/2)]/RT

ν

coordinate perpendicular to boundary of model cell

ϱ1

resistivity of bubble-free solution

ϱ2

resistivity of separator

ϱbc

resistivity of bubble curtain

ϕ

potential in cell

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References

  1. [1]
    Z. Nagy,J. Appl. Electrochem. 6 (1976) 171.Google Scholar
  2. [2]
    J. Jorne and J. F. Louvar,J. Electrochem. Soc. 127 (1980) 298.Google Scholar
  3. [3]
    F. Hine, M. Yasuda, M. Watanabe and M. Kurate,Soda to Enso (Soda and Chlorine)7 (1981) 281.Google Scholar
  4. [4]
    F. Hine and K. Murakami,J. Electrochem. Soc. 128 (1981) 64.Google Scholar
  5. [5]
    L. J. J. Janssen, J. J. M. Geraets, E. Barendrecht and S. D. J. Van Stralen,Electrochim. Acta 27 (1982) 1207.Google Scholar
  6. [6]
    F. Hine M. Yasuda, Y. Ogata and K. Hara,J. Electrochem. Soc. 131 (1984) 83.Google Scholar
  7. [7]
    C. Elsner and F. Coeuret,J. Appl. Electrochem. 15 (1985) 567.Google Scholar
  8. [8]
    F. Hine, M. Yasuda, R. Nakamura and T. Noda,J. Electrochem. Soc. 122 (1975) 1185.Google Scholar
  9. [9]
    O. Lanzi and R. F. Savinell,130 (1983) 799.Google Scholar
  10. [10]
    H. Vogt,Electrochim. Acta 26 (1981) 1311.Google Scholar
  11. [11]
    Y. Nishiki, K. Aoki, K. Tokuda and H. Matsuda,J. Appl. Electrochem. 14 (1984) 653.Google Scholar
  12. [12]
    Y. Nishiki, K. Aoki, K. Tokuda and H. Matsuda,16 (1986) 291.Google Scholar
  13. [13]
    D. A. Bruggeman,Ann. Physik,24 (1935) 636.Google Scholar
  14. [14]
    F. Chorlton, ‘Vector and Tensor Methods’, Ellis Horwood, New York (1977) p. 92.Google Scholar
  15. [15]
    Y. Nishiki, K. Aoki, K. Tokuda and H. Matsuda,J. Appl. Electrochem. 16 (1986) 615.Google Scholar

Copyright information

© Chapman and Hall Ltd 1987

Authors and Affiliations

  • Yoshinori Nishiki
    • 1
  • Koichi Aoki
    • 2
  • Koichi Tokuda
    • 2
  • Hiroaki Matsuda
    • 2
  1. 1.Research and Development CenterPermelec Electrode LtdFujisawa, Kanagawa PrefectureJapan
  2. 2.Department of Electronic Chemistry, Graduate School at NagatsutaTokyo Institute of TechnologyYokohamaJapan

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