Table 7: Electrochemical impedance parameters and percentage inhibition efficiency for N80 steel in 15% HCl in the absence and the presence of the inhibitors at different concentrations at 303 K.

InhibitorConcentration (ppm) (Ω cm2) ( F cm2) % IE

Blank 25 252

20 74 15866.32
50 85 12270.58
AMPT 100 110 8777.25
150 142 7382.37
200 178 6785.97

20 66 8262.42
50 75 6667.71
APT 100 102 5375.47
150 126 3280.13
200 150 2683.31

20 63 7160.52
50 74 5866.12
ACPT 100 80 4168.58
150 107 2476.53
200 134 2081.03