Adsorption and corrosion inhibition characteristics of 2–(chloromethyl) benzimidazole for C1018 carbon steel in a typical sweet corrosion environment: Effect of chloride ion concentration and temperature

Benzimidazole derivatives are emerging as promising corrosion inhibitors for oil and gas application because they exhibit high efficiency and very good environmental profile. Although long alkyl and phenyl chains enhance their efficiency, they also increase their toxicity. Finding benzimidazole derivatives devoid of long hydrocarbon chains and with lower toxicity has become a priority. 2–(chloromethyl)benzimidazole (CMB), with log Po/w = 2.2, has been investigated as a promising low-toxic sweet corrosion inhibitor for C1018 carbon steel in CO2–saturated NaCl solution under static condition using experimental and theoretical approaches. At 25 ◦C, Open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization (PDP) techniques confirm that CMB is an anodic-type sweet corrosion inhibitor which is able to form a protective layer on the steel surface and provide inhibition efficiency of 97.54% at 10 ppm. The efficiency increased to 98.40% and 98.58% upon increasing the temperature to 40 ◦C and 60 ◦C, respectively but decreased to 96.32% and 94.76% as the salt concentration was raised to 5.0% and 7.0% NaCl, respectively. The latter was attributed to the antagonistic competition between Cl– ions and CMB for anodic adsorption. The CMB–steel interaction is facilitated by the free electrons around N heteroatoms and C = C bonds, based on FTIR analysis and computational calculations. This eventually ameliorates the surface degradation of the steel during the sweet corrosion at 25 and 60 ◦C. CMB performance is highly comparable with reported sweet corrosion inhibitors with higher toxicity values

Investigation into the adsorption and inhibition properties of sodium octanoate against CO2 corrosion of C1018 carbon steel under static and hydrodynamic conditions

Sodium octanoate (Na-oct), a simple, naturally-abundant, cheap and low-toxic organic molecule has been investigated for its adsorption and inhibition properties against the CO2 corrosion of C1018 carbon steel in 3.5 % NaCl under static (0 rpm) and hydrodynamic conditions (1000 rpm). At open circuit potential (OCP) under static condition, a Langmuir-type adsorption of Na-oct modified the dielectric property of the steel-solution interface by lowering double layer capacitance and increasing resistance to charge transfer, based on electrochemical impedance spectroscopy (EIS) analysis. Under this condition, potentiodynamic polarization (PDP) analysis showed that Na-oct adsorbed more preferentially on anodic sites of steel surface and impacted ∼96 % inhibition efficiency. Hydrodynamic condition at 1000 rpm caused a Langmuir and Temkin adsorption mechanism and diminished the Na-oct efficiency to ∼86 %. FTIR characterization revealed that the inhibitor adsorption was enabled by its COO– functional group. Computational modeling, using DFT and MDS, confirmed the experimental findings

Handling heat‐stable salts in post‐combustion CO₂ capture: A detailed survey

The generation of heat‐stable salts (HSSs) in alkanolamine solutions for CO2 capture processes, which is adapted for power plant technologies, exists irrespective of the class of amine solution used for the capture process. Their presence do not only trigger decrements in the CO2 absorption capacities of the solvents and contribute to further alkanolamine degradation, but also result in foaming and loss of solvents, which impacts system economics and threatens the environment. HSSs also promote the corrosiveness of the metallic structures of capture systems by lowering the pH and increasing the conductivity of the absorbent solutions. Overall, these effects substantially subvert the reliability and integrity of CO2 capture units. This survey affords sufficient background on the existence of HSSs by unraveling the flow process in a typical alkanolamine‐based CO2 capture unit with respect to their formation points and potential threats. Furthermore, the major HSSs removal and alkanolamine reclamation methodologies (electrodialysis, distillation, ion exchange, electromagnetic separation, and solvent extraction) were comprehensively explored. We believe that this review paper will benefit researchers across disciplines as we continue to explore new and complex solvent formulations to minimize the cost of CO2 capture while maximizing efficiency<br/

Developments in anticorrosive organic coatings modulated by nano/microcontainers with porous matrices

The durability and functionality of many metallic structures are seriously threatened by corrosion, which makes the development of anticorrosive coatings imperative. This state-of-the-art survey explores the recent developments in the field of anticorrosive organic coatings modulated by innovations involving nano/microcontainers with porous matrices. The integration of these cutting-edge delivery systems seeks to improve the protective properties of coatings by enabling controlled release, extended durability, targeted application of corrosion inhibitors, and can be co-constructed to achieve defect filling by polymeric materials. The major highlight of this review is an in-depth analysis of the functionalities provided by porous nano/microcontainers in the active protection and self-healing of anticorrosive coatings, including their performance evaluation. In one case, after 20 days of immersion in 0.1 M NaCl, a scratched coating containing mesoporous silica nanoparticles loaded with an inhibitor benzotriazole and shelled with polydopamine (MSNs-BTA@PDA) exhibited coating restoration indicated by a sustained corrosion resistance rise over an extended period monitored by impedance values at 0.01 Hz frequency, rising from 8.3 × 104 to 7.0 × 105 Ω cm2, a trend assigned to active protection by the release of inhibitors and self-healing capabilities. Additionally, some functions related to anti-fouling and heat preservation by nano/microcontainers are highlighted. Based on the literature survey, some desirable properties, current challenges, and prospects of anticorrosive coatings doped with nano/microcontainers have been summarized. The knowledge gained from this survey will shape future research directions and applications in a variety of industrial areas, in addition to advancing smart corrosion prevention technology

Characterization and Experimental and Computational Assessment of Kola nitida Extract for Corrosion Inhibiting Efficacy

Kola nitida (KN) extract was assessed for its ability to hinder corrosion of mild steel in 0.1 M HCl solution by means of gravimetric and electrochemical tests. KN extract was found to efficiently retard mild steel corrosion in this system, with the effect becoming more pronounced as KN extract concentration increased and slightly subdued as immersion time lengthened. From the polarization and impedance results, KN extract was seen to affect both the cathodic and the anodic reactions following adsorption of organic species from the extract on the metal/solution interface. The presence of such organics was confirmed by UV–visible spectrophotometry and gas chromatography–mass spectroscopy analyses. Selected constituents of the extract were modeled in order to assess their adsorbability using the density functional theory (DFT) and revealed remarkably high interaction energies, which corroborate the experimental findings