Evaluation of Corrosion Mitigation Properties of Pyridinium-Based Ionic Liquids on Carbon Steel in 15% HCl under the Hydrodynamic Condition: Experimental, Surface, and Computational Approaches

The corrosion process severely damages the carbon steel during the acidization. The present investigation described the corrosion inhibition application of two ionic liquids: 1-Butylpyridinium chloride (BPC) and 1-Butylpyridinium hexafluorophospate (BPH), for the protection of carbon steel in 15 % HCl under the hydrodynamic condition at 1500 rpm. The estimated results obtained by weight loss support the inhibi-tive performance of BPs are 90.0 % (BPC) and 72.5 % (BPH). The EIS results point out the rising values of Rct with the increasing amount of BPs and approach the highest value of 262.4 52 cm2 (BPC) and 125.4 52 cm2 (BPH). The PDP reveals the anodic nature of BPs inhibitive action. The Dubinine Radushkevich (D-RIM) adsorption isotherm model provides accurate fitting estimated data. The negative values of DHoads repre-sent the exothermic nature of adsorption. The contact angle value is less (26.4 degrees) for BPs free steel sample. However, a significant increase occurs in the contact angle values upon adding BPC (84.9 degrees) and BPH (67.8 degrees). The SEM, optical profilometry, contact angle, and XPS confirmed the presence of an adsorptive layer of BPs. DFT further suggests the better inhibitive performance of BPC than BPH.(c) 2023 Elsevier B.V. All rights reserved.