影像科学与光化学 ›› 1992, Vol. 10 ›› Issue (4): 289-296.DOI: 10.7517/j.issn.1674-0475.1992.04.289

• 研究论文 •    下一篇

漂白过程的电化学研究——Ⅱ.碘离子对Fe(Ⅲ)络合物氧化金属银反应的影响

刘春艳1, U. Nickel2   

  1. 1. 中国科学院感光化学研究所, 北京 100101;
    2. Erlangeo-Nurnberg大学理论和物理化学研究所, 德国
  • 收稿日期:1991-02-23 修回日期:1992-03-02 出版日期:1992-11-20 发布日期:1992-11-20
  • 通讯作者: 刘春艳

ELECTROCHEMICAL STUDIES ON THE BLEACHING PROCESS Ⅱ.THE EFFECT OF IODIDE ON THE OXIDATION OF METALLIC SILVER WITH Fe(Ⅲ)-COMPLEXES

LIU CHUN-YAN1, ULRICH NICKEL2   

  1. 1. Institute of Photographic Chemistry, Academia Sinica Beijing, 100101, P. R. China;
    2. Institute für Physikalische and Theoretische Chemie der University Erlangen-Nürnberg, Germany
  • Received:1991-02-23 Revised:1992-03-02 Online:1992-11-20 Published:1992-11-20

摘要: 当溶液中含有溴化物时,Fe(Ⅲ)络合物与银电极之间的反应较慢。如果使用碘化物、反应会加快。电流加和原理和溶度积常数可用来解释碘化物对Fe(Ⅲ)络合物氧化金属银反应加速作用机理。在电极表面上氧化形成的AgI较之溴化银更难用硫代硫酸盐络合除去。 在含有Fe(Ⅲ)络合物的溴化物和碘化物混合溶液中,卤化银在银电极表面上的生成速率随溶液中碘化物浓度的增大先是下降,然后上升。因为AgI较低的溶度积常数,AgI/Ag的阳极化曲线与Fe(Ⅲ)络合物/Fe(Ⅱ)络合物氧化还原对的阴极化曲线间较负的混合电位,在浸入含有少量碘化物和一定浓度溴化物的Fe(Ⅲ)络合物溶液的银电极表面上,优先生成AgI。

关键词: 恒电位法, 卤化银, 照相漂白

Abstract: In this paper, it was found that, when bromide is present in the solution of Fe(Ⅲ)-com-plexes, it makes a slower redox reaction between Fe(Ⅲ)-complexes and metallic silver.If iodide is present instead, the same reaction will be accelerated.The additivity principle for electric current and the solubility product of AgX may account for the acceleration effect of iodide.However, Agl is more difficult to remove completely from the electrode surface than AgBr.When both bromide and iodide are present, the formation rate of AgX on the electrode surface first decreases and then increases with increasing iodide concentration.Due to the lower solubility product of Agl and more negative mixed potential between Fe(Ⅲ)-complex/Fe(Ⅱ)-complex and Ag/AgI, Agl is formed preferably on the surface of the electrode, when it was dipped into the bromide solution containing little iodide.

Key words: galvanostat, bleaching process, silver halide