Table 7 Electrochemical parameters of Cu oxidation in 0.6 M NaCl in the absence and presence of different concentrations of ME, QF and nBF at ambient temperature.
Sample | Concn. of inhibitor, ppm | ba mV dec− 1 | bc mV dec− 1 | Ecorr, mV | Icorr , mA cm− 2 | Corros. rate µm year− 1 | R, KΩ cm2 | IE % |
|---|---|---|---|---|---|---|---|---|
Blank | 0 | 82.7 | – 45.4 | – 220 | 0.0180 | 189.5 | 0.56 | |
nBF | 20 | 23.5 | – 28.4 | – 175 | 0.0030 | 50.2 | 1.72 | 83.3 |
40 | 25.4 | – 32.1 | – 175 | 0.0027 | 46.5 | 1.82 | 85.0 | |
60 | 22.9 | – 35.1 | – 144 | 0.0010 | 13.5 | 4.86 | 94.4 | |
80 | 28.7 | – 40.3 | – 192 | 0.0045 | 62.9 | 1.36 | 75.0 | |
100 | 17.5 | – 20.5 | – 205 | 0.0043 | 61.3 | 1.02 | 76.1 | |
ME | 20 | 18.7 | – 24.7 | – 184 | 0.0044 | 49.6 | 1.07 | 75.6 |
40 | 35.9 | – 52.6 | – 186 | 0.0039 | 45.0 | 1.45 | 78.3 | |
60 | 34.5 | – 37.9 | – 172 | 0.0030 | 40.9 | 1.48 | 83.3 | |
80 | 23.4 | – 27.4 | – 177 | 0.0053 | 64.2 | 0.97 | 70.6 | |
100 | 30.8 | – 35.6 | – 175 | 0.0083 | 102.1 | 0.01 | 53.9 | |
QF | 20 | 18.2 | – 17.3 | – 197 | 0.0047 | 32.3 | 1.68 | 73.9 |
40 | 30.7 | – 44.6 | – 154 | 0.0051 | 61.6 | 0.95 | 71.6 | |
60 | 25.0 | – 31.5 | – 185 | 0.0060 | 72.9 | 0.76 | 66.1 | |
80 | 44.0 | – 39.6 | – 198 | 0.0065 | 71.7 | 0.69 | 63.9 | |
100 | 21.8 | – 26.4 | – 213 | 0.0089 | 100 | 0.64 | 50.6 |
