Electrochemical assessment of phenol and triazoles derived from phenol (BPT) on API 5L X52 steel immersed in 1 M HCl

The corrosion inhibition of phenol triazoles was tested with several halogens by means of electrochemical impedance and potentiodynamic polarization. We observed the importance of the 1,2,3-triazole ring in the chemical structure because significant inhibition efficiencies (η) > 90% were achieved at low concentrations with the different halogens. These compounds have a physisorption-type adsorption process, in accordance with the Langmuir model. For long immersion times, the organic inhibitor BPTI showed good corrosion protection during 504 hours of immersion with η > 80%. Furthermore, the hydrodynamic conditions proved that organic molecules experience a desorption process related to the different rotation velocities employed. Finally, it was demonstrated by SEM that the corrosion velocity is diminished when using the BPTI inhibitor at 50 ppm.