The corrosion of iron rotating hemispheres in 1 M sulfuric acid: An electrochemical impedance study

Technical Report · Mon Jun 01 00:00:00 EDT 1987

OSTI ID:6199042

Haili, C C

This research project consists of experimental investigation and theoretical analysis of the corrosion of iron in sulfuric acid. Objectives were: to elucidate the processes governing the complex behavior of the iron-sulfuric acid system, particularly the reaction mechanism, the passivation process, and the observed limiting current and electrochemical oscillations; to improve our fundamental understanding of metal corrosion and passivation phenomena; and to demonstrate the application of the electrochemical impedance method as a tool for the study of electrochemical systems. Experiments carried out were: (1) potentiodynamic experiments to determine the anodic polarization curve, especially the passivation curve; (2) potentiostatic experiments recording the sustained current oscillations that occur within a certain potential range on the limiting current plateau; (3) measurement of the ac impedance of the system at several points along the anodic polarization curve, using a frequency response analyser. Rotating hemispherical iron electrodes were used in most of these experiments. The Kramers-Kronig relations were applied to the electrochemical impedance. The experimental results were compared with theoretical predictions in order to elucidate the behavior of the iron-sulfuric acid system. A concentrated-solution model was used to calculate the impedance, in addition to analytic calculations using infinitely-dilute-solution theory. The calculated results for the reaction mechanism and conditions tested did not agree with the experimental results. 226 refs., 5 figs.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6199042
• Report Number(s): LBL-23776; ON: DE87014679
• Resource Relation: Other Information: Thesis. Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ELECTRODES
DISSOLUTION
ELECTRIC IMPEDANCE
IRON
ELECTROCHEMICAL CORROSION
ALTERNATING CURRENT
AQUEOUS SOLUTIONS
CHARGE EXCHANGE
ELECTROCHEMISTRY
ELECTROLYTIC CELLS
EQUATIONS
EXTRAPOLATION
FREQUENCY DEPENDENCE
KRAMERS-KRONIG CORRELATION
MASS TRANSFER
OSCILLATORS
PASSIVATION
POLARIZATION
SULFURIC ACID
THEORETICAL DATA
CHEMICAL REACTIONS
CHEMISTRY
CORRELATIONS
CORROSION
CURRENTS
DATA
DISPERSIONS
ELECTRIC CURRENTS
ELECTRONIC EQUIPMENT
ELEMENTS
EQUIPMENT
HYDROGEN COMPOUNDS
IMPEDANCE
INFORMATION
INORGANIC ACIDS
METALS
MIXTURES
NUMERICAL DATA
NUMERICAL SOLUTION
SOLUTIONS
TRANSITION ELEMENTS
360105* - Metals & Alloys- Corrosion & Erosion
400400 - Electrochemistry