Journal of Applied Electrochemistry

, Volume 21, Issue 11, pp 986–990 | Cite as

Pulsed electrogeneration of bubbles for electroflotation

  • N. K. Khosla
  • S. Venkatachalam
  • P. Somasundaran


Fine bubbles of the size required for many processes such as electroflotation can be generated by electrolysis. A large number of factors such as electrode material, electrode surface/morphological properties, pH and current density affect the gas bubble size distribution. This work is aimed at studies on the effect of interrupted current (pulsed) electrolysis on the generation of gas bubbles. A microcomputer-controlled current source designed to generate the required pulses is described along with typical results obtained with this system. It was observed that a decrease in duty cycle at a given pH and average current density causes an increase in fine sized bubbles and concomitant increase in bubble flux. A mechanism based on local potential gradients is proposed to explain this phenomenon.


Physical Chemistry Electrode Material Duty Cycle Current Source Typical Result 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    P. J. Sides, in ‘Modern aspects of Electrochemistry’ (edited by R. E. White, J. O'.M. Bockris and B. E. Conway) 18, Plenum Press, New York (1986) p. 303.Google Scholar
  2. [2]
    H. Vogt, in ‘Comprehensive, Treatise on Electrochemistry’, Vol. 6, Plenum Press, New York (1983) p. 445.Google Scholar
  3. [3]
    N. Ahmed and G. J. Jameson,Int. J. Min. Process. 14 (1985) 195.Google Scholar
  4. [4]
    A. A. Mamakov, in ‘Modern State and Perspective of Electrolytic Flotation’, Vol.I (edited by V. P. Schtiinsta), Kishinev (1975) pp. 3–66 (in Russian).Google Scholar
  5. [5]
    G. B. Raju and P. R. Khangaonkar,Int. J. Min. Process. 9 (1982) 133.Google Scholar
  6. [6]
    H. Ledesma and M. Guzman, in ‘Production and Proceessing of Fine Particles’ (edited by A. J. Plumpton), Canadian Institute of Mining and Metallurgy, Montreal (1988) pp. 195–202.Google Scholar
  7. [7]
    E. A. Cassell, K. M. Kaufman and E. Matijevic,Water Research 9 (1975) 1017.Google Scholar
  8. [8]
    A. Coehn,Z. Elektrochem. 29 (1923) 1.Google Scholar
  9. [9]
    B. N. Kabanov, ‘Electrochemistry of metals and adsorption’, Nauka, Moscow (1966).Google Scholar
  10. [10]
    B. N. Kabanov and A. N. Frumkin,Z. Phys. Chem. 165 (1933) 539.Google Scholar
  11. [11]
    B. N. Kabanov and N. I. Vashchenko, Electrocapillary phenomena and wettability of materials,Proceedings Academy of Science USSR, Chemical Series (1936) 735.Google Scholar
  12. [12]
    A. Coehn and H. Neumann,Z. für Phys. 20 (1923) 54.Google Scholar
  13. [13]
    A. T. Kuhn,Chemical Processing 20 (1974), June 9–12, July 5–7.Google Scholar
  14. [14]
    V. I. Klassen and V. A. Moukrosov, ‘An Introduction to The Theory of Flotation’, Butterworths, London (1963) p. 493.Google Scholar
  15. [15]
    N. P. Brandon, G. H. Kelsall, S. Levine and A. L. Smith,J. Appl. Electrochem. 15 (1985) 485.Google Scholar
  16. [16]
    D. R. Ketkar, R. Mallikarjunan and S. Venkatachalam,J. Electrochem. Soc. India 37 (1988) 313.Google Scholar
  17. [17]
    J. P. Glas and J. W. Westwater,Int. J. Heat Mass Transfer 7 (1964) 1427.Google Scholar
  18. [18]
    N. P. Brandon and G. H. Kelsall,J. Appl. Electrochem. 15 (1985) 475.Google Scholar
  19. [19]
    P. Sides and J. Tobias,J. Electrochem. Soc. 132 (1985) 583.Google Scholar
  20. [20]
    R. D. Doherty, ‘Physical Metallurgy Part II’, (edited by R. W. Cahn and P. Haasen), North-Holland, Amsterdam (1963) pp. 967–75.Google Scholar
  21. [21]
    L. F. Murr, ‘Interfacial Phenomena in Metals and Alloys’, Addison-Wesley, Keading MA (1975) pp. 259–80.Google Scholar
  22. [22]
    N. P. Brandon, Ph.D. thesis, University of London (1985).Google Scholar

Copyright information

© Chapman & Hall 1991

Authors and Affiliations

  • N. K. Khosla
    • 1
  • S. Venkatachalam
    • 1
  • P. Somasundaran
    • 2
  1. 1.Department of Metallurgical EngineeringIndian Institute of TechnologyBombayIndia
  2. 2.Henry Krumb School of MinesColumbia UniversityNew YorkU.S.A.

Personalised recommendations