The activation energies for the dissolution of iron in solutions of different anions have been determined. The reactions were carried out in air-saturated acid solutions in order to simulate a natural corrosion environment.
The procedures used to measure the corrosion kinetics were similar to those employed in a previously reported investigation.1 Ingot iron HP (99.77% Fe, 0.13%Cu, 0.04% Ni, 0.01% Mn, 0.01% Sn) was used. The coupons were suspended in 0.50M solutions of NaCl, NaBr, Nal, NaNO3, Na2HPO4, Na2SO4, and NaClO4 at pH 2.70 and also H2SO4 at pH 2.70. Salt solutions were prepared with certified ACS reagent chemicals, the pH being adjusted to ±0.01 by dropwise addition of concentrated H2SO4. Temperature control was provided by a thermostatted water bath which was constant to ±0.1 C. Experiments were conducted at 30,...
