Journal of Applied Electrochemistry

, Volume 13, Issue 4, pp 473–487

Water desalting by means of electrochemical parametric pumping

I. The equilibrium properties of a batch unit cell
  • Y. Oren
  • A. Soffer
Papers

Abstract

It was shown previously that adsorption of ions at the electrical double layer of a high specific surface area carbon electrode can serve for water desalination. This is effected by assembling two such electrodes in a cell, cycling electronic charge between them and applying periodic synchronous pumping of the liquid through the cell. This process has been termed Electrochemical Parametric Pumping (ECPP). In the present article, modified charge coordinates, desalting efficiencies, isopotentiograms (analogous to adsorption isotherms) and optimization considerations of the two adsorptive electrode batch unit of the ECPP were derived and analysed on the basis of the propterties of each single electrode separately.

Nomenclature

a0,a0+,a,a+

ionic activities at the inlet and outlet solutions.

c1,c2

specific double layer capacities of electrodes 1 and 2 (μF g−1)

Ce

specific cell capacitance (μF g−1)

C

solution concentration (mol cm−3)

E1,E2

potential of electrodes 1 and 2 versus a reference electrode

ΔE

potential difference between the two electrodes (V)

E0

potential attained by the electrodes after short-circuiting

F

Faraday constant

g1,g2

weights of electrodes 1 and 2 (g)

i

denotes electrode 1 or 2 in a two electrode system

K

dielectric constant of the solution at the double layer region

ΔnS

change in salt content in the solution in one electrode system (moles)

Δn+, Δn

total amount of adsorbed cations and anions in one electrode system (moles)

nst

total amount of salt adsorbed on the electrodes (moles)

ns

amount of salt adsorbed per unit weight of electrode material (moles g−1)

ni,ni+

amount of anions and cations adsorbed on unit weight of electrodei (wherei=1, 2) (mol g−1)

Δq

the change in total electrode charge in one electrode system (C)

qi

total charge per unit weight of electrodei (C g−1)

qi+,qi

cationic and anionic charges per unit weight of electrodei (C g−1)

qe,qd

independent charge coordinates (C g−1)

R

gas constant

T

absolute temperature

w

electrical work of charging the double layer (eV)

ε0

free space permittivity

μ1,μ2

relative weights or elelctrode 1 and 2 respectively

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    Y. Oren and A. Soffer,J. Electrochem. Soc. 125 (1978) 869.Google Scholar
  2. [2]
    R. H. Wilhelm and N. H. Sweed, Science159 (1968) 522.Google Scholar
  3. [3]
    R. L. Pigford, B. Baker III and D. E. Blum;I. EC. Fundam. 8 (1969) 144.Google Scholar
  4. [4]
    R. H. Wilhelm, A. W. Rice and A. R. Bendelius,Ind. Eng. Chem. 5 (1969) 144.Google Scholar
  5. [5]
    R. G. Rice,Sep. Purif. Methods 5 (1976) 139.Google Scholar
  6. [6]
    A. Soffer, Ph.D. thesis, Israel Institute of Technology, Haifa, Israel (1969).Google Scholar
  7. [7]
    A Soffer and M. Folman,J. Electroanal. Chem. 38 (1972) 25.Google Scholar
  8. [8]
    D. C. Grahame and B. A. Soderberg,J. Chem. Phys. 22 (1954) 449.Google Scholar
  9. [9]
    A. Soffer,J. Electroanal. Chem. 40 (1972) 153.Google Scholar
  10. [10]
    A. N. Frumkin, O. S. Petrii and B. B. Damaskin,Electrokhimiya 6 (1970) 614.Google Scholar
  11. [11]
    R. Parsons, in ‘Modern Aspects of Electrochemistry’, Vol. I, (edited by J. O'M. Bockris) Butterworths, London (1954).Google Scholar
  12. [12]
    J. Th. G. Overbeek, in ‘Colloid Science’, Vol. 1, (edited by H. R. Kruyt) Elsevier Publishing Company Inc. New York, (1949) p. 194.Google Scholar
  13. [13]
    A. M. Johnson and J. Newman,J. Electrochem. Soc. 118 (1971) 510.Google Scholar
  14. [14]
    P. Delahay, ‘Double Layer and Electrode Kinetics’, Interscience Publishers, New York, London, Sydney (1945) p. 55.Google Scholar
  15. [15]
    Idem, ibid, p. 35.Google Scholar
  16. [16]
    D. M. Mohilner, in ‘Electroanalytical Chemistry’ (edited by A. J. Bard), Marcel Dekker, New York (1966) p. 304.Google Scholar
  17. [17]
    D. C. Grahame,J. Chem. Phys. 21 (1953) 1054.Google Scholar
  18. [18]
    S. D. Argade and E. Gileadi, in Electrosorption, (edited by E. Gileadi), Plenum Press, New York (1967).Google Scholar
  19. [19]
    M. Yaniv and A. Soffer,J. Electrochem. Soc. 123 (1976) 506.Google Scholar
  20. [20]
    H. Tobias, M.Sc. thesis, Ben Gurion University, Beer Sheva, Israel (1979).Google Scholar
  21. [21]
    D. C. Grahame, M. A. Poth and J. I. Cummings,JACS 74 (1952) 4427.Google Scholar
  22. [22]
    Y. Oren, A. Soffer,J. Appl. Electrochem. 13 (1983) 489.Google Scholar

Copyright information

© Chapman and Hall Ltd 1983

Authors and Affiliations

  • Y. Oren
    • 1
  • A. Soffer
    • 1
  1. 1.Nuclear Research CenterNegev, Beer ShevaIsrael

Personalised recommendations