Integrating experimental, surface activity, and theoretical computing methodologies to assess potassium polyoxyethylene laury ether phosphate as corrosion inhibitor

Abstract

In the present investigation, the integrating experimental, surface activity, and theoretical computing methodologies are employed to evaluate the corrosion inhibitor properties of an anionic surfactant (potassium polyoxyethylene laury ether phosphate (POE-SURF)) in a 1.0 HCl solution for steel (AISI 1008). The experimental investigations demonstrated that the highest inhibitory effectiveness of approximately 98.8 % was achieved with 0.1 mM of POE-SURF. The physical adsorption of POE-SURF on the AISI 1008 surface was conducted by the inhibitive effect, which occurred based on the Langmuir adsorption isotherm. POE-SURF acted as a mixed kind's inhibitor. The presence of POE-SURF significantly raises the energy barrier for the corrosion process, resulting in notably higher activation energy of 70.58 kJ mol⁻¹ .The small energy gap (ΔE_g) confirms POE-SURF's strong inclination to coordinate with metal surfaces by electron donation. A Mulliken charge of the POE-SURF confirms that the negative charged atom can adsorb on the metal surface by donating electron to the 3^d orbital. The examined surfactant POE-SURF exhibits outstanding surface activities, leading to good adsorption behavior