Understanding xanthone derivatives as novel and efficient corrosion inhibitors for P110 steel in acidizing fluid: Experimental and theoretical studies

Abstract

The corrosion of metal during the acidizing process is destructive. Past research has revealed the development of corrosion inhibitors that are only effective in reducing the acidic conditions. The present study aims to fill this gap by the development of two xanthone derivatives, namely 12-(4-chlorophenyl)-9,9-dimethyl-8,9,10,12-tetrahydro-11H-benzo[a]xanthen-11-one (BX-Cl) and 9,9-dimethyl-12-(4-nitrophenyl)-8,9,10,12-tetrahydro-11H-benzo[a]xanthen-11-one (BX-NO2), using microwave irradiation techniques and well-characterized by IR, NMR, and MS used for the corrosion inhibition of P110 steel in 15% HCl. The performances of BX-Cl and BX-NO2were further enhanced via the addition of KI. Weight loss studies confirmed the enhancement in η% from 62.10 to 92.21% for BX-Cl and 47.36–84.21% for BX-NO2) upon increasing their concentration from 50 to 200 mg/L. The performances of BX-Cl and BX-NO2 decreaseuponincreasing the temperature. EIS revealed that the Rct values increase upon increasing the amount of BX-Cl and BX-NO2 and reach a maximum value of 644.8 Ω cm2. PDP confirmed the reduction in theicorr value from 630 to 54 μA/cm2. The Freundlichisotherm explains the perfect fitting of the obtained data. SEM, AFM, and XPS confirmed the presence of an adsorptive layer of BX-Cl and BX-NO2. DFT and MD further indicate that BX-Cl is a better inhibitor than BX-NO2.