THE DIFFERENCE EFFECT AND ANODIC BEHAVIOR OF ZIRCONIUM DISSOLVING IN HYDROFLUORIC ACID

Journal Article · Wed Jun 01 04:00:00 EDT 1960 · Journal of the Electrochemical Society (U.S.) Absorbed Electrochem. Technol.

DOI:https://doi.org/10.1149/1.2427732· OSTI ID:4156035

Straumanis, M E; James, W J; Custead, W C

Zirconium dissolving in hydrofluoric acid exhibited a positive difference effect of such an efficiency that the hydrogen volume developed by the internal polarization current was completely overbalanced by the effect. As with other metals the effect was independent of the concentration of the acid and was accompanied by a strong shift in potential of the Zr electrode toward noble values (passivation). Similar potential changes were also recorded in presence of salts or more noble metals while they were displaced by the Zr. Simultaneously, the rate of dissolution of Zr dropped (nearly to zero with Pt/sup 4+/ additions). In the latter case the black hydride film on the surface disappeared and the Zr turned bright and shiny (passive Zr). A decrease in formation of the hydride film was observed in other cases of anodic polarization. The activity of Zr returned when the anodic current was cut off. As the effect of local currents due to anodic polarization is reduced to a minimum, the high rate of dissolution of Zr is explained by direct chemical action of Zr with molecular HF. (auth)

• Research Organization: Univ. of Missouri, Rolla
• Sponsoring Organization: USDOE
• NSA Number: NSA-14-015638
• OSTI ID: 4156035
• Journal Information: Journal of the Electrochemical Society (U.S.) Absorbed Electrochem. Technol., Journal Name: Journal of the Electrochemical Society (U.S.) Absorbed Electrochem. Technol. Vol. Vol: 107; ISSN JESOA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANODES
BEHAVIOR
CHEMISTRY
ELECTRIC POTENTIAL
ELECTRODES
FILMS
HYDRIDES
HYDROFLUORIC ACID
HYDROGEN
IONS
PASSIVATION
PLATINUM
POLARIZATION
SURFACES
ZIRCONIUM