Corrosion Inhibition of Novel Prepared Cationic Surfactants for API N80 Carbon Steel Pipelines in Oil Industries

Corrosion potential and theoretical studies of fabricated Schiff base for carbidic austempered ductile iron in 1M H2SO4 solution

In this body of work, a chemical known as 2-cyano-N-(4-morpholino benzyl dine) acetohydrazide (CMBAH) is explored for its ability to suppress the carbidic austempered ductile iron (CADI) corrosion in 1M H2SO4. Density functional theory was used in experiments and theoretical investigations to investigate the inhibiting impact. The corrosion of CADI alloys in 1M H2SO4 produced a corrosion resistance superior to that of CADI heat treatment (H.T.). As-cast carbidic ductile iron (CDI) 4 alloy with 1.5%t Cr-Nb has a corrosion rate (C.R.) of 11.69 mm/year, which drops to 5.31 mm/year at HT-275 °C and 6.13 mm/year at HT-375 °C. When describing the adsorption of inhibitors, the Langmuir adsorption isotherm is the most effective method. The findings of the Gads show that the inhibition was induced mainly by the physisorption on the surface CADI alloys. In addition to this, it was found that the results of the experiments and the hypotheses were largely harmonious with one another. The formation of protective layers on the CADI surfaces is also visible in the images captured by the SEM. In 1M H2SO4, these Schiff base inhibitors effectively prevent corrosion caused by CADI. However, the combination of inhibitors leads to a fine microstructure with ausferrite and narrow ferrite needles, promoting corrosion resistance. The CADI needles rated an upper ausferritic microstructure with wide ferrite needles.

Preparation of zwitterionic ionic surfactants-based sulphonyl for steel protections: Experimental and theoretical insights

Designating an organic inhibitor with a specific chemical structure that actively participates in steel protection by increasing adsorption on the steel surface. Based on that, we synthesized three zwitterionic surfactants based on azomethine with different hydrophobic chain lengths labeled ZWSO, ZWSD, and ZWSH. The presence of azomethine group, electrons, and heteroatoms in the zwitterionic surfactant’s amphipathic structure helped to improve C-steel protection. Their inhibitory activity toward steel corrosion was investigated utilizing electrochemical impedance spectroscopy (EIS), gravimetrical, and potentiodynamic polarization techniques. Importantly, the surfactant tail influenced corrosion inhibition performance; as surfactant tail length increased, so did inhibition efficiency due to increased adsorption affinity. The inhibition efficiencies of ZWSO, ZWSD, and ZWSH are 87.15, 89.82, and 91.36%, respectively. Tafel data clarified that ZWSO, ZWSD, and ZWSH inhibitors behave as mixed-type inhibitors following the modified Langmuir isotherm. The inhibitors can adsorb physiochemically on the steel surface with ∆G ads ranges from −38.48 to −44.6 kJ mol−1. The SEM confirms that the morphology of C-steel becomes smoother because of inhibitor adsorption. The DFT and MCs output data supported the experimental performance of the tested ZWSO, ZWSD, and ZWSH inhibitors and especially their dependence on surfactant tail length.

Suppression of steel corrosion via some gemini cationic surfactant-based Schiff base: experimental and theoretical investigations

Steel is involved extensively in engineering vast constructing units in many industries and can undergo to corrosion by some chemical and/or electrochemical reactions with the environment. Therefore, designating an organic inhibitor with a specific chemical structure will participate in steel protection via enhancing their adsorption on the steel surface. Three gemini cationic surfactants based on azomethine with different hydrophobic tails labeled GSBI8, GSBI12, and GSBI16 have been designated and evaluated as corrosion inhibitors utilizing electrochemical impedance spectroscopy (EIS), gravimetrical and potentiodynamic polarization techniques. Importantly, the surfactant tail regulated the corrosion inhibition performance; with increasing the surfactant tail length, their inhibition efficiency enhanced because of their higher adsorption affinity. The inhibition efficiency of GSBI8, GSBI12, and GSBI16 reached 95.52, 96.72, and 97.1% respectively (EIS measurements). The Tafel examination clarified that GSBI8, GSBI12, and GSBI16 inhibitors behave as mixed type inhibitors following the modified Langmuir isotherm. The inhibitors adsorption on C-steel was confirmed by SEM surface examination. Finally, the DFT and MCs point of views investigation supported the experimental performance of the tested GSBI8, GSBI12, and GSBI16 inhibitors and specially their dependence on surfactant tail length.

Application of surfactants as anticorrosive materials: A comprehensive review

Corrosion is the degradation of a metal due to its reaction with the environment. One of the most efficient ways of securing metal surfaces from corrosion is the use of corrosion inhibitors. Their efficacy is connected to their chemical composition, their molecular structures, and their adsorption affinities on the metal surface. This review article focuses on the prospects of different types of monomeric and gemini surfactants, mixed surfactants systems, surfactants- additives mixed systems, inhibitors-surfactants (as additives) mixed systems, and ionic liquid based surfactants as promising corrosion-inhibiting formulations in the aqueous phase and the role of surfactants in developing protective coatings. The analysis starts with an accurate overview of the characteristics, types, and structure-property-performance relationship of anti-corrosion formulations of such inhibitors.