Advertisement

Journal of the American Oil Chemists Society

, Volume 47, Issue 10, pp 374–378 | Cite as

Isomerization during hydrogenation of soap: II. Potassium elaidate and potassium linoleate

  • D. S. Raju
  • M. R. Subbaram
  • K. T. Achaya
Technical

Abstract

Potassium elaidate in slightly alkaline solution was hydrogenated for up to 7 hr with 1.5% of Rufert nickel catalyst at 150 C and 20 kg/sq cm pressure. Potassium linoleate was similarly hydrogenated with 1.0% catalyst for 7 hr, and the hydrogenation continued for another 7 hr after addition of 0.5% fresh catalyst. Periodic samples from each were analyzed for component acids. The positional isomers in thecis andtrans monoenes, isolated by preparative argentation thin layer (TLC) or column chromatography, were estimated after oxidation to dicarboxylic acids. Some diene fractions were isolated for further examination. In potassium elaidate hydrogenation,cis monoenes were initially produced in considerable amounts, but to a lesser extent thereafter. Positional isomers were similarly distributed in bothcis andtrans monoenes after prolonged hydrogenation. In the hydrogenation of potassium linoleate, a drop in iodine value (IV) of 60 units occurred in the first hour, and 38% oftrans monoenes (in which the 10- and 11-monoenes constitute 32% each) were formed. The IV then fell only slowly, and up to 38% ofcis monoene (mostly 9- and 12-isomers) was formed. Addition of fresh catalyst caused a major shift ofcis monoenes totrans forms. The diene fraction was mostly nonconjugated material with the first double bond at the 9, 8 and 10-positions. Minor amounts of conjugated dienes were present as well as a dimeric product.

Keywords

Diene Linoleate Methyl Linoleate Iodine Value Fresh Catalyst 
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.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Raju, D. S., M. R. Subbaram and K. T. Achaya, JAOCS45, 165 (1968).Google Scholar
  2. 2.
    Allen, R. R., and A. A. Kiess, Ibid.32, 400 (1955).Google Scholar
  3. 3.
    Blekkingh, J. J. A., H. J. J. Janssen and J. G. Keppler, Rec. Trav. Chim.76, 35 (1957).CrossRefGoogle Scholar
  4. 4.
    Litchfield, O., J. E. Lord, A. F. Isbell and R. Reiser, JAOCS40, 553 (1963).Google Scholar
  5. 5.
    Kinomura, S., and T. Tsuchiya, J. Chem. Soc. Japan, Industr. Chem. Sect.55, 639 (1952).Google Scholar
  6. 6.
    Scholfield, C. R., E. P. Jones, J. A. Stolp and J. C. Cowan, JAOCS35, 405 (1958).Google Scholar
  7. 7.
    Hilditch, T. P., and S. P. Pathak, Proc. Roy. Soc. London198A, 328 (1949).Google Scholar
  8. 8.
    Feuge, R. O., E. R. Cousins, S. P. Fore, E. F. DuPre and R. T. O'Connor, JAOCS30, 454 (1953).Google Scholar
  9. 9.
    Allen, R. R., and A. A. Kiess, Ibid.33, 355 (1956).Google Scholar
  10. 10.
    Cousins, E. R., W. A. Guice and R. O. Feuge, Ibid.36, 24 (1959).CrossRefGoogle Scholar
  11. 11.
    Allen, R. R., Ibid.33, 301 (1956).Google Scholar
  12. 12.
    Swern, D., and W. E. Parker, Ibid.30 5 (1953).Google Scholar
  13. 13.
    von Rudloff, E., Can. J. Chem.34, 1413 (1956).CrossRefGoogle Scholar
  14. 14.
    Cowan, J. C., JAOCS39, 534 (1962).Google Scholar
  15. 15.
    Coenen, J. W. E., and H. Boerma, Fette Seifen Anstrichm.70, 8 (1968).CrossRefGoogle Scholar
  16. 16.
    Raju, D. S., M. R. Subbaram and K. T. Achaya Ibid. Fette Seifen Anstrichm.72 (In Press).Google Scholar

Copyright information

© The American Oil Chemists' Society 1970

Authors and Affiliations

  • D. S. Raju
    • 1
  • M. R. Subbaram
    • 1
  • K. T. Achaya
    • 1
  1. 1.Regional Research LaboratoryHyderabad-9India

Personalised recommendations