Influence of pH on the localized corrosion of iron

Technical Report · Sun Jun 01 00:00:00 EDT 1986

DOI:https://doi.org/10.2172/6511920· OSTI ID:6511920

Webley, R; Henry, R

The influence of pH on the pitting corrosion of iron in chloride and sulfate solutions was determined using two artificial pit apparatuses to obtain the pH near the surface of the pit bottom. A glass membrane electrode and an antimony electrode were used to measure pH in the two apparatuses. Using solutions of NaCl and Na/sub 2/SO/sub 4/ at current densities of 0.5, 5.0, and 10 mA/cm/sup 2/ pH's in the range 5 to 6 were obtained with the first apparatus. The antimony probe did not measure pH accurately in solutions of 1 N NaCl and 1 N Na/sub 2/SO/sub 4/ and had an error of approximately 2 pH units. A one-dimensional transport model was developed to predict pH variations around the pit mouth and inside the pit. The validity of this model was not verified due to the relative lack of precision with pH measurement techniques.

• Research Organization: Massachusetts Inst. of Tech., Brookhaven, NY (USA). School of Chemical Engineering Practice-Brookhaven Station
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6511920
• Report Number(s): BNL-39687; MIT/BNL-86-6; ON: DE87010452; TRN: 87-023497
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
IRON
PITTING CORROSION
AQUEOUS SOLUTIONS
PH VALUE
SODIUM CHLORIDES
SODIUM SULFATES
ALKALI METAL COMPOUNDS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CORROSION
DISPERSIONS
ELEMENTS
HALIDES
HALOGEN COMPOUNDS
METALS
MIXTURES
OXYGEN COMPOUNDS
SODIUM COMPOUNDS
SOLUTIONS
SULFATES
SULFUR COMPOUNDS
TRANSITION ELEMENTS
360105* - Metals & Alloys- Corrosion & Erosion