The Anodic Behavior of Zinc in Potassium Hydroxide Solution

Abstract

A study of the anodic behavior of horizontal zinc electrodes in KOH solution has shown that the equationholds for concentrations in the range 1-13.8M and passivation times in the range 10-800 sec. The constant k depends on the KOH concentrations and attains a maximum value in the region of 8.5M KOH; i~, the maximum current density attainable without passivation, from a least squares fit is very near zero in all cases. From the linear parts of the curves connecting anode potential and time, values of dE/dT indicate that the conductivity of the anodic product prior to passivation depends on the concentration of the KOH electrolyte. This conductivity passes through a maximum in the same region as that which produces the longest passivation times.

Observations of an Operating Zinc‐Pore Electrode

“…This time/polarization behavior resembled that previously reported by Hampson et al (11) for a planar electrode in unstirred electrolyte. About 3-5 sec before onset of the severe passivation, small white particles could be seen near the middle of the anode in the electrolyte, unattached to the surface as evidenced by a movement apparently in accord with small convective disturbances caused by the bubbles.…”

“…This was Paper 44 presented at the Atlanta, Georgia, Meeting of the Society, Oct. [9][10][11][12][13][14] 1977.…”

Role of tannic acid based rust converter on formation of passive film on zinc rich coating exposed in simulated concrete pore solution

“…Zinc surface in alkaline solutions dissolves under the influence of a number of complex corrosion products formed on its surface [37][38][39]. Its reaction with hydroxyl ions of SPS initially forms zinc hydroxide:…”

Molybdenum–phosphorus compounds based passivator to control corrosion of hot dip galvanized coated rebars exposed in simulated concrete pore solution

“…The improved performance of passivated surface than unpassivated surface in controlling the corrosion of HDG in concrete pore solution may be explained by considering the reactions of zinc in alkaline solutions. Zinc dissolves in alkali under the influence of a number of complex corrosion products formed on its surface [15,16,41]. Its reaction with SPS initially produces zinc hydroxide:…”

“…In saturated lime solutions, the formation of a stable layer of calcium hydroxy zincate is reported [16,17]. In sodium and potassium hydroxide solutions, it was earlier presumed that the layers of corrosion products on zinc surface were complex and comprised of zinc oxide in combination with a porous layer of zinc hydroxide [41]. It was suggested that the zincate ions formed in Eq.…”