Synergistic effect of propargyl alcohol, octadecylamine, and 1,3-dibutyl thiourea for API P110 alloys in acetic and formic acidic solutions used in oil well acidizing

Abstract The synergism in an organic formulation containing propargyl alcohol, octadecylamine, and 1,3-dibutyl thiourea was evaluated. The formulation efficiency was tested for API P110 steel in acetic + formic acidic media by weight loss, potentiodynamic polarization, linear polarization resistance, confocal laser scanning microscopy, and scanning electron microscopy. The formulation was characterized using Fourier transform infrared spectroscopy. Gravimetric analysis (353–393 K) revealed efficiencies above 98% and confirmed the importance of the multi-component formulation, which acts as a mixed-type inhibitor. The inhibiting film was confirmed by scanning electron microscopy. The substances evaluated show a synergistic effect when employed together.