Table 5 EIS parameters for API X60 mild steel in CO2 saturated 3.5% NaCl without and with 50 ppm TBA at pH 4 at different immersion times.
Conc. | Time (h) | Rs (Ω cm2) | Rct (Ω cm2) | Rf (Ω cm2) | Y0×104 (sn/Ω cm2) | n | Cf (µF cm−2) | χ2 × 104 | %IE |
|---|---|---|---|---|---|---|---|---|---|
Blank | 2 | 4.9 ± 0.03 | 135.4 ± 0.33 | — | 7.91 ± 0.00 | 0.79 ± 0.01 | — | 5.4 | — |
12 | 4.9 ± 0.06 | 125.3 ± 0.72 | — | 14.92 ± 0.00 | 0.76 ± 0.02 | — | 6.4 | — | |
24 | 4.9 ± 0.06 | 117.1 ± 0.73 | — | 16.2 ± 0.00 | 0.74 ± 0.02 | — | 4.5 | — | |
48 | 4.9 ± 0.06 | 107.7 ± 0.76 | — | 15.70 ± 0.00 | 0.72 ± 0.02 | — | 2.7 | — | |
72 | 5.0 ± 0.05 | 100.9 ± 0.43 | — | 15.17 ± 0.00 | 0.76 ± 0.01 | — | 2.8 | — | |
50 ppm | 2 | 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 |
12 | 6.1 ± 0.05 | 4656.0 ± 6.86 | 8.6 ± 1.01 | 2.08 ± 0.00 | 0.77 ± 0.00 | 44.1 | 1.2 | 97.0 | |
24 | 6.2 ± 0.05 | 6225.0 ± 1.43 | 19.4 ± 1.66 | 2.41 ± 0.00 | 0.76 ± 0.00 | 53.7 | 8.0 | 98.0 | |
48 | 6.2 ± 0.05 | 7032.0 ± 1.07 | 26.4 ± 0.46 | 2.50 ± 0.00 | 0.79 ± 0.02 | 57.6 | 1.5 | 98.4 | |
72 | 6.2 ± 0.05 | 7243 ± 1.11 | 26.6 ± 1.76 | 2.82 ± 0.00 | 0.79 ± 0.00 | 57.7 | 1.2 | 98.5 |
