CORROSION ENGINEERING DIGEST
Online ISSN : 1884-1155
Print ISSN : 0010-9355
ISSN-L : 0010-9355
Volume 15, Issue 11
Displaying 1-6 of 6 articles from this issue
  • [in Japanese]
    1966 Volume 15 Issue 11 Pages 481-485
    Published: November 15, 1966
    Released on J-STAGE: November 25, 2009
    JOURNAL FREE ACCESS
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  • Adsorption of Mercaptan on Cu-Surface by Displacing the Pre-Adsorbed Water
    Seiichi Fujii, Kenzô Kobayashi
    1966 Volume 15 Issue 11 Pages 486-490
    Published: November 15, 1966
    Released on J-STAGE: November 25, 2009
    JOURNAL FREE ACCESS
    In our previous reports, we concluded that adsorption of high molecular-weight mercaptan on Cu-surface could be made up by elevating the temperature of filming solution, or by adding suitable amount of stronger electron-accepting substances such as ether, alcohol, acid, ester, and amine. At first these substances pulled adsorbed water off and then mercaptan could be adsorbed on the site where the adsorbed water had been removed. These twostep processes could be explained by following equations:
    1) M: O-H-H→heatM+O-H-H→+RSHM: S-H-R+H2O
    2) M: O-H-H→+R′-O-R′M+O-H…O-R′-R′→+RSHM: S-H-R+O-H-H…O-R′-R′
    M: metal, R, R′: alkyl radical
    In our experiments test coupons were always filmed in xylene solution of a corrosion inhibitor preliminarily, and the filmed coupons were dipped in corrosive media to get the efficiency of the inhibitor. And in the case of the equation 2) we found that higher inhibition efficiency could be obtained only when proton-accepting substance in suitable dose, and its excess amount caused lower inhibition.
    In this report, we studied on the relation between the amount of proton-accepting substance and mercaptan. And results were summarized as follows:
    1) Mercaptan could be adsorbed only when ether, as a proton-accepting substance, removed the adsorbed water by its hydrogen-bonding with the water.
    2) When excess amount of ether in the filming solution, the ether was preferentially adsorbed on Cu-surface and mercaptan could not be adsorbed, as it occupied the place where mercaptan to be adsorbed. As the ether was more easily desorbed at lower temperature, ether film on the surface could not protect the metal more effectively thann mercaptan film in the corrosive media.
    3) Quantitative relations might be dependent not on the ratio of ether to mercaptan but on thee ratio of ether to the adsorbed water on Cu-surface.
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  • Rikuro Ôtsuka
    1966 Volume 15 Issue 11 Pages 491-494
    Published: November 15, 1966
    Released on J-STAGE: November 25, 2009
    JOURNAL FREE ACCESS
    It was found that the anodic polarization behavior of titanium in sulfuric acid solution is affected by the presence of titanium hydride layer formed on the surface by the corrosion reaction. When the hydride was present, a new peak appeared in the anodic polarization curve at the potentials of -0.1-0V vs. S. C. E. The height of this peak increased with the increase of the amount of hydride formed on the surface prior to the polarization measurement. The more the amount of hydride was and the higher the peak was, the more time was required to activate titanium after the anodic passivation. Since the starting potential of the peak was slightly more noble than the hydrogen redox potential of the sulfuric acid solution used, the new peak was attributed to the oxidation reaction of hydrogen absorbed in or reacted with titanium. The hydrogenation of titanium by the cathodic polarization in sodium sulfate solution gave the same effect on the anodic polarization curve in sulfuric acid.
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  • A. H. Roebuck, T. R. Pritchett, [in Japanese]
    1966 Volume 15 Issue 11 Pages 495-499
    Published: November 15, 1966
    Released on J-STAGE: November 25, 2009
    JOURNAL FREE ACCESS
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  • D. A. Jones, N. D. Greene, [in Japanese]
    1966 Volume 15 Issue 11 Pages 500-506
    Published: November 15, 1966
    Released on J-STAGE: November 25, 2009
    JOURNAL FREE ACCESS
    Download PDF (1054K)
  • [in Japanese]
    1966 Volume 15 Issue 11 Pages 507-512
    Published: November 15, 1966
    Released on J-STAGE: November 25, 2009
    JOURNAL FREE ACCESS
    Download PDF (980K)
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