Synergistic effect of polyethylene glycols and rare earth Ce4+ on the corrosion inhibition of carbon steel in sulfuric acid solution: electrochemical, computational, and surface morphology studies

Abstract

The inhibition effect of two selected polyethylene glycols (PEGs) with different molecular weight and the synergistic effect with rare earth Ce 4? ions on corrosion of carbon steel in 0.1 M H 2 SO 4 solution has been investigated by using electrochemical measurements, scanning electron microscopy, and quantum chemical calculations. The inhibition efficiency (Z%) increased with increasing PEG concentration and molecular weight and decreased with increasing temperature. The adsorption of the PEGs obeyed the Langmuir adsorption isotherm. Potentiodynamic polarization studies showed that the PEGs were mixed-type inhibitors of corrosion by H 2 SO 4 . The results reveal that incorporation of PEGs with Ce 4? ions improved the inhibition performance. The Z% value for the PEGs in combination with Ce 4? was higher than the sum of the Z% values for the individual PEGs and Ce 4? ions, confirming a synergistic effect. Some quantum chemical parameters were calculated to corroborate the experimental results.

Novel Quaternary Ammonium‐Based Cationic Surfactants: Synthesis, Surface Activity and Evaluation as Corrosion Inhibitors for C1018 Carbon Steel in Acidic Chloride Solution

“…In addition, the values of b c in the absence and presence of investigated inhibitors are higher than 118 mV/dec. It indicates that the corrosion reaction proceeded mainly by charge transfer and substance diffusion [1]. The values of b c show a slight change with increasing surfactant dose, indicating the influence of these compounds on the kinetics of hydrogen evolution.…”

“…Carbon steel is widely used in different engineering and industrial applications, including designs and construction, where it is deployed in various service environments containing aggressive solutions [1]. In industrial applications, 15% HCl and 20% H 2 SO 4 are employed for scale removal treatments and chemical and electrochemical etching of metals [2,3].…”

“…This phenomenon is due to the occurrence of hetero atoms as well as multiple bonds or aromatic rings in the compound chemical structure [6]. It has been reported that during the acidizing procedure, a variety of organic compounds act as corrosion inhibitors for steel, such as alkenylphenones [7][8][9], amides, nitrogen-containing heterocycles [10], pyridine and its derivatives or salts, nitriles, imminium salts, thiourea derivatives, triazoles, quinoline derivatives, thiosemicarbazide, quaternary salts, thiocyanates [11,12], and surfactants [1,[13][14][15].…”

Inhibition Effect of 2,2’-Bipyridyl on the Corrosion of Austenitic Stainless Steel in 0.5M H2 SO4

“…Without 2,2'-Bipyridyl, the impedance spectrum is composed of two loops: a semicircular high frequency (HF) capacitive loop attributed to charge transfer reaction 26,27 and an inductive loop at low frequencies (LF) attributed either to relaxation process due to FeSO 4 species' adsorption or the inhibitor species on metal surface 28 , and / or at passive film's re-dissolution 29 . With 2,2'-Bipyridyl, the impedance spectra are composed of a single capacitive loop indicating that the corrosion process is controlled by charge transfer phenomenon 11 .…”

Effect of Polyethylene Glycol 12000 on Morphology and Corrosion Behavior of TiO(OH)2/MnO2/PEG12000 Composite Electrodeposited on Pure Copper

“…The addition of polyethylene glycol (PEG) as an additive appears to be the most suitable solution. This choice is based on its interesting proprieties of corrosion inhibitor [9][10][11], size reducer [12,13] and especially its ability to affect the physical proprieties of the medium without changing the reaction path of the composite formation.…”