Cleaner corrosion inhibitors using Peumus boldus Molina formulations in oil well acidizing fluids: gravimetric, electrochemical and DFT studies

Eco-friendly inhibitors are an alternative to reduce environmental and human health problems related conventional employed in oil well acidizing. In the present study, boldo (Peumus boldus) was investigated as a corrosion inhibitor for API P110 carbon steel 2 M 15% HCl. A two-level full factorial design (23) used evaluate extraction time (90 210 min), temperature (313 343 K) solute/ethanol ratio (0.15 0.35 g of sheet/mL ethanol). The extracts were characterized by phenolic content, Fourier-transform infrared spectroscopy, Proton nuclear magnetic resonance, relative density refraction index. extract concentration HCl evaluated at 303 313 K, achieving 87% efficiency. Binary formulations developed order partially use inhibitors. Two performed better 333 K. Electrochemical tests provided information about metal-solution interface absence presence formulations, indicating that these mixed Confocal microscopy elucidated metallic surface morphology. Surface characterization techniques confirmed inhibitory film on surface. Density functional theory indicated boldine molecule stable acidic phase, exhibiting improved anticorrosive properties.