Electrochemical screening of organic and inorganic inhibitors for the corrosion of ASTM A-470 steel in concentrated sodium hydroxide solution

Journal Article · Wed May 01 04:00:00 EDT 1985 · Corrosion (Houston); (United States)

DOI:https://doi.org/10.5006/1.3582001· OSTI ID:5162494

Moccari, A; MacDonald, D D

The corrosion of ASTM A-470 turbine disk steel in concentrated sodium hydroxide solution (10 mol/kg) containing sodium silicate, sodium dihydrogen phosphate, sodium chromate, aniline and some of its derivatives, tannic acid, L-(-)-phenylalanine (aminopropionic acid) and octadecylamine as potential inhibitors has been studied using the potentiodynamic, AC impedance, and Tafel extrapolation techniques. All tests were performed at 115 + or - 2 C. The anodic and cathodic polarization data show that aniline and its derivatives, L-(-)-phenylalanine, NaH/sub 2/PO/sub 4/, Na/sub 2/SiO/sub 3/, and Na/sub 2/CrO/sub 4/ inhibit the anodic process, whereas tannic acid inhibits the cathodic reaction. Octadecylamine was found to inhibit both the anodic and cathodic processes. The mechanisms of inhibition for some of these compounds have been inferred from the wide band width frequency dispersions of the interfacial impedance.

• Research Organization: Carolina Power and Light, New Hill, North Carolina
• OSTI ID: 5162494
• Journal Information: Corrosion (Houston); (United States), Journal Name: Corrosion (Houston); (United States) Vol. 41:5; ISSN CORRA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALANINES
ALKALI METAL COMPOUNDS
ALLOYS
AMINES
AMINO ACIDS
ANILINE
ANODIZATION
AROMATICS
CARBOXYLIC ACIDS
CATHODIC PROTECTION
CHEMICAL COATING
CHEMICAL REACTIONS
CHEMISTRY
CHROMATES
CHROMIUM COMPOUNDS
COMPARATIVE EVALUATIONS
CORROSION
CORROSION INHIBITORS
CORROSION PROTECTION
DEPOSITION
ELECTROCHEMICAL COATING
ELECTROCHEMICAL CORROSION
ELECTROCHEMISTRY
ELECTROLYSIS
HYDROGEN COMPOUNDS
HYDROXIDES
HYDROXY COMPOUNDS
IRON ALLOYS
IRON BASE ALLOYS
LYSIS
MACHINERY
MATERIALS TESTING
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHENOLS
PHOSPHATES
PHOSPHORUS COMPOUNDS
POLYPHENOLS
SILICATES
SILICON COMPOUNDS
SODIUM COMPOUNDS
SODIUM HYDROXIDES
SODIUM PHOSPHATES
SODIUM SILICATES
STEELS
SURFACE COATING
TANNIC ACID
TESTING
TRANSITION ELEMENT COMPOUNDS
TURBINES
TURBOMACHINERY