Table 7 EIS parameters for API X60 steel in CO2 saturated 3.5% NaCl without and with 50 ppm TBA at pH 4 at different temperatures.
Conc. | Temp (°C) | Rs (Ω cm2) | Rct (Ω cm2) | Rf (Ω cm2) | Y0×104 (Ω.cm2 S−n) | n | Cf (µF/cm2) | χ2 × 10–4 | %IE |
|---|---|---|---|---|---|---|---|---|---|
Blank | 25 | 4.9 ± 0.03 | 135.4 ± 0.33 | — | 7.91 ± 0.00 | 0.79 ± 0.01 | — | 5.4 | — |
40 | 4.2 ± 0.04 | 65.3 ± 0.56 | — | 12.1 ± 0.00 | 0.73 ± 0.02 | 130 | 0.2 | — | |
60 | 2.8 ± 0.03 | 41.1 ± 0.42 | — | 13.1 ± 0.00 | 0.74 ± 0.02 | 130 | 0.39 | — | |
80 | 2.1 ± 0.03 | 40.4 ± 0.21 | — | 13.9 ± 0.00 | 0.77 ± 0.04 | 0.16 | 0.37 | — | |
50 ppm | 25 | 4.6 ± 0.05 | 3762.0 ± 0.90 | 6.2 ± 2.99 | 1.40 ± 0.00 | 0.78 ± 0.03 | 38 | 9.0 | 96.3 |
40 | 5.0 ± 0.04 | 2697.0 ± 1.36 | 4.9 ± 0.38 | 1.00 ± 0.00 | 0.73 ± 0.00 | 0.44 | 4.0 | 97.4 | |
60 | 2.8 ± 0.02 | 2228.0 ± 0.09 | 2.7 ± 0.03 | 0.73 ± 0.00 | 0.74 ± 0.00 | 0.22 | 4.5 | 98.0 | |
80 | 2.3 ± 0.02 | 2190.0 ± 0.60 | 2.4 ± 0.13 | 1.97 ± 0.00 | 0.77 ± 0.00 | 0.50 | 5.6 | 98.2 |
