Imidazolium, Pyridinium and Dimethyl‐Ethylbenzyl Ammonium Derived Compounds as Mixed Corrosion Inhibitors in Acidic Medium

Abstract

Seven cationic surfactants: 1-methyl-3-tetradecyl imidazolium bromide, 1-methyl-3-hexadecyl imidazolium bromide, N,N-tetradecyl pyridinium bromide, N,N-hexadecyl pyridinium bromide, N,N-dimethyl-N-ethylbenzyl ammonium bromide, N,N-dimethyl-N-ethylbenzyl ammonium laurate and N,N-dimethyl-N-ethylbenzyl ammonium acetate, were investigated at different doses (10, 25, 50, 100, and 200 ppm) as corrosion inhibitors for steel grade API 5L X52 in hydrochloric acid 2 M using a weight loss technique, impedance and polarization resistance methods. The corrosion inhibition of steel grade API 5L X52 of the cationic surfactants was attributed to their molecular structure (heterocyclic ring, hydrophobic chain length and counterion) that enhances adsorption onto steel surface. The best protective efficiency of the film was higher than 90% (N,N-Dimethyl-N-ethylbenzyl ammonium acetate). It is important to know how organic inhibitor films grown on the metallic surface in order to achieve superior corrosion inhibition, hence experimental findings were described by Langmuir adsorption isotherm. The Electrochemical Impedance Spectroscopy spectrums were fitted by means of the Voigt model.

Sulfur and phosphorus heteroatom‐containing compounds as corrosion inhibitors: An overview

“…On the other hand, metallic surface become negatively charged because of the adsorption of counterions of electrolytes on the positively charged metallic surface. The two appositively charged species interact from each other by electrostatic force of attraction; therefore during initial stage adsorption, behavior of inhibitors on metallic surface obeys the physisorption mechanism . However, during the course of metal‐inhibitor interactions, the non‐bonding electrons of heteroatoms and π‐electrons of multiple bonds get transferred (charge donation) into the d‐orbital of the surface metallic atoms (eg, Fe) that results in the formation of coordinate bonding between them.…”

Environmentally Friendly Corrosion Inhibitors

“…Ionic liquids (ILs) deserve particular attention due to the rapid grown in the number of applications in the Oil Industry [134], and particularly within the topic of synthetic EFCIs, these have shown an effective performance as inhibitors of various metals and alloys [135][136][137][138][139][140][141][142][143][144][145][146][147][148][149][150][151].…”

Synthesis and inhibition of N-alkyl-2-(4-hydroxybut-2-ynyl) pyridinium bromide for mild steel in acid solution: Box–Behnken design optimization and mechanism probe

“…Most of the well-known inhibitors used in acidic environment are aliphatic or aromatic compounds containing polar groups, heteroatoms as well as conjugated double bonds [7][8][9][10][11][12]. Furthermore, aromaticity and electron density of inhibitors are found to influence the adsorption of inhibitor molecules on metal surface [13,14].…”