Experimental, DFT and molecular dynamics simulation on the inhibition performance of the DGDCBA epoxy polymer against the corrosion of the E24 carbon steel in 1.0 M HCl solution

Novel Imine-Tethering Cationic Surfactants: Synthesis, Surface Activity, and Investigation of the Corrosion Mitigation Impact on Carbon Steel in Acidic Chloride Medium via Various Techniques

Novel imine-tethering cationic surfactants, namely (E)-3-((2-chlorobenzylidene)amino)-N-(2-(decyloxy)-2-oxoethyl)-N,N-dimethylpropan-1-aminium chloride (ICS-10) and (E)-3-((2-chlorobenzylidene)amino)-N,N-dimethyl-N-(2-oxo-2-(tetradecyloxy)ethyl)propan-1-aminium chloride (ICS-14), were synthesized, and the chemical structures were elucidated by various spectroscopic approaches. The surface properties of the target-prepared imine-tethering cationic surfactants were investigated. The effects of both synthesized imine surfactants on carbon steel corrosion in a 1.0 M HCl solution were investigated by weight loss (WL), potentiodynamic polarization (PDP), and scanning electron microscopy (SEM) methods. The outcomes show that the inhibition effectiveness rises with raising the concentration and diminishes with raising the temperature. The inhibition efficiency of 91.53 and 94.58 % were attained in the presence of the optimum concentration of 0.5 mM of ICS-10 and ICS-14, respectively. The activation energy (E_a) and heat of adsorption (Q_ads) were calculated and explained. Additionally, the synthesized compounds were investigated using density functional theory (DFT). Monte Carlo (MC) simulation was utilized to understand the mechanism of adsorption of inhibitors on the Fe (110) surface.

A comprehensive assessment of carbon steel corrosion inhibition by 1,10-phenanthroline in the acidic environment: insights from experimental and computational studies

1,10-Phenanthroline (PHN) is a nitrogen-containing heterocyclic organic compound that is widely used in a variety of applications, including chemosensors, biological studies, and pharmaceuticals, which promotes its use as an organic inhibitor to reduce corrosion of steel in acidic solution. In this regard, the inhibition ability of PHN was examined for carbon steel (C48) in a 1.0 M HCl environment by performing electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), mass loss, and thermometric/kinetic. Additionally, scanning electron microscopy (SEM) was used to examine the surface morphology of C48 immersed in 1.0 M HCl protected with our inhibitor. According to the PDP tests, increasing the PHN concentration resulted in an improvement in corrosion inhibition efficiency. Besides, the maximum corrosion inhibition efficiency is about 90% at 328 K. Furthermore, the PDP assessments demonstrated that PHN functions as a mixed-type inhibitor. The adsorption analysis reveals that our title molecule mechanism is due to physical-chemical adsorption, as predicted by the Frumkin, Temkin, Freundlich, and Langmuir isotherms. The SEM technique exhibited that the corrosion barrier occurs due to the adsorption of the PHN compound through the metal/1.0 M HCl interface. In addition, the computational investigations based on a quantum calculation using density functional theory (DFT), reactivity (QTAIM, ELF, and LOL), and molecular-scale by Monte Carlo (MC) simulations confirmed the experimental results by providing further insight into the mode of adsorption of PHN on the metal surface, thus forming a protective film against corrosion on the C48 surface.

Theoretical and electrochemical evaluation of tetra-cationic surfactant as corrosion inhibitor for carbon steel in 1 M HCl

Recently, scientist study the role of surfactants for carbon steel corrosion protection. In the present study, newly tetra-cationic surfactant (CS4: 1,N1'-(ethane-1,2-diyl) bis (N1, N2-didodecyl-N2-(2- (((E)-3-hydroxy-4-methoxy-benzylidene)amino)ethyl)ethane-1,2-diaminium) chloride) based on Schiff-base compound(5,5'-((1E,17E)-2,5,8,11,14,17-hexaazaoctadeca-1,17-diene-1,18-diyl)bis(2-methoxyphenol) was synthesised, purified and characterized using FTIR and ¹HNMR spectroscopy. The synthesized Tetra-cationic surfactant (CS4) was evaluated as anti-corrosion for carbon steel (CS-metal) in aggressive 1 M HCl using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques (PDP). CS4 compound had a good surface-active property by reducing the surface tension as a result to the hydrophobic chains role. The prepared CS4 behaved as hybrid inhibitor (mixed-type) by blocking the anodic and cathodic sites. CS4 exhibited good inhibition efficiency reached 95.69%. The surface morphology of CS-metal was studied using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS)confirming the anti-corrosive effect of CS4 compound returned into the adsorption process of CS4 molecules over CS-metal which obeyed Langmuir adsorption isotherm. The inhibitive effect of CS4 was supported by theoretical quantum chemical studies using the density functional theory (DFT), Monte Carlo (MC) and Molecular Dynamic (MD) simulation.

Electrochemical, computational, chemical and surface investigation on novel synthesized imine surfactants as an eco-friendly inhibitor for carbon steel corrosion in 1 M HCl.. [DOI: 10.21203/rs.3.rs-2403672/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Novel quaternary ammonium surfactants based on imines, namely, (E)-3-((2-chlorobenzylidene)amino)-N-(2-(decyloxy)-2-oxoethyl)-N,N-dimethylpropan-1-aminium chloride, (ICS-10) and (E)-3-((2-chlorobenzylidene)amino)-N,N-dimethyl-N-(2-oxo-2-(tetradecyloxy)ethyl)propan-1-aminium chloride (ICS-14) were synthesized and their chemical structures were determined by different spectroscopic approaches. The surface properties of the target-prepared surfactants were investigated. The effects of both synthesized imine surfactants on carbon-steel corrosion in 1.0 M HCl solution were investigated by weight loss (WL), potentiodynamic polarization (PDP), and scanning electron microscopy (SEM) methods. The outcomes show that the inhibition effectiveness rises with raising the concentration and diminishes with raising the temperature. The inhibition efficiency of 91.53 and 94.58% were attained in the optimum concentration of 0.5 mM of ICS-10 and ICS-14, respectively. The activation energy (Ea) and heat of adsorption (Qads) were calculated and explained. Also, the synthesized compounds were investigated using density functional theory (DFT). Monte Carlo (MC) simulation was utilized to understand the mechanism of adsorption of inhibitors on the Fe (110) surface.

A Review on Interactions between Amino Acids and Surfactants as Well as Their Impact on Corrosion Inhibition

Amino acid-surfactant interactions are central to numerous studies because of their increased effectiveness in chemical, biological, household and industrial use. This review will focus on the impact and effect of the physicochemical properties, temperature, pH, and surfactant chain length of the amino acid for detailed exploration of amino acids and surfactants in aqueous medium. The impact of cosolvent on self-aggregation, critical micelle concentration (CMC), and binding affinity with other biomolecules, as well as amino acid-surfactant interactions, are the epicenters. The results show that increasing the temperature causes negative enthalpy for ionic surfactants and micellization, implying that micellization and amino acids are thermodynamically spontaneous and exothermic, accompanied by positive entropy. As these physicochemical studies are additive, the amino acid and ionic surfactant interactions provide clues on protein unfolding and denaturation under different media, which further changes with a change in physiological conditions like pH, cosolvent, chain length, and temperature. On varying the pH, the net charge of the amino acid also changes and, subsequently, the binding efficiency of the amino acids to the surfactants. The presence of cosolvent causes a lowering in the hydrophobic chain, which changes the surfactant's CMC. At a reduced CMC, the hydrophobic characteristic of amino acid-surfactant associations is amplified, leading to rapid denaturation of proteins that act as propulsion under the influence of extended chain surfactants. Amino acids are one of the most intriguing classes of chemicals that produce high inhibitory efficacy. Amino acids are also a component of proteins and therefore, found in a significant part of the human body, further making them a promising candidate as corrosion inhibitors. In this review article, authors have also focused on the collection and investigation for application of amino acid-surfactant interactions in corrosion inhibition. Various predictive studies/in silico studies are also reported by many research groups, such as density functional theory (DFT) calculations and molecular dynamics simulations to obtain tentative electronic, structural, and physiochemical characteristics like energies of the highest occupied molecular orbitals and lowest unoccupied molecular orbitals, binding energy, Gibb's free energy, electronegativity, polarizability, and entropy. In silico studies are helpful for the mechanism predictions of the process occurring on metal surfaces.

Analysis of Elastic Properties of Polypropylene Composite Materials with Ultra-High Molecular Weight Polyethylene Spherical Reinforcement

This study proposes an isotropic composite material with enhanced elastic properties based on a reinforcement mechanism using ultra-high molecular weight polyethylene (UHMWPE) spherical molecules. Elastic properties are predicted through finite element analysis by randomly mixing UHMWPE using polypropylene (PP) as a matrix. The change in elastic properties of the composite is calculated for volume fractions of UHMWPE from 10 to 70%. Furthermore, the results of finite element analysis are compared and analyzed using a numerical approach. The results show that the physical properties of the composite material are enhanced by the excellent elastic properties of the UHMWPE, and the finite element analysis results confirm that it is effective up to a volume fraction of 35%.

Adsorption of antibiotic cefazolin in organoclay fixed-bed column: characterization, mathematical modeling, and DFT-based calculations

Cefazolin (CFZ) is an antibiotic widely used in veterinary and human medicine that has been detected in high residual levels in the environment and is therefore considered an emerging contaminant. This work evaluated the adsorption of this contaminant by Spectrogel® type C organoclay, in continuous mode using a fixed-bed column. The fluid dynamics and the effect of the CFZ concentration were evaluated. In addition, prior and post-process organoclay were characterized. The continuous system under the conditions of C₀ = 0.3 mmol/L and Q = 0.1 mL/min presented lower values of mass transfer zone (5.88 cm), whereas the system with C₀ = 0.5 mmol/L and Q = 0.1 mL/min achieved higher CFZ adsorption capacity (20 µmol/g). Phenomenological and mass-transfer models were applied to the experimental data. The dual-site diffusion (DualSD) model better described the breakthrough (BTC) data. Furthermore, density functional theory (DFT) calculation was performed at the molecular level to provide a better comprehension of CFZ adsorption.

An Experimental and Theoretical Investigation of the Efficacy of Pantoprazole as a Corrosion Inhibitor for Mild Steel in an Acidic Medium

The corrosion behavior of mild steel in a 1 M aqueous sulfuric acid medium in the presence and absence of the drug Pantoprazole was investigated using potentiodynamic polarization and quantum chemical calculations as well as Monte Carlo and molecular dynamic simulations. The potentiodynamic experiments indicated that this molecule, as a result of its adsorption on a mild steel surface, functioned as a mixed inhibitor. The goal of the study was to use theoretical calculations to acquire a better understanding of how inhibition works. The adsorption behavior of the examined compounds on the Fe (1 1 0) surface was calculated using a Monte Carlo simulation. Furthermore, the molecules were studied using density functional theory (DFT), especially the PBE functional, to determine the relationship between the molecular structure and the corrosion inhibition behavior of the chemical under research. The adsorption energies of Pantoprazole (in its three different protonation states) iron were calculated more precisely using molecular mechanics with periodic boundary conditions (PBC). The predicted theoretical parameters were found to be in agreement with the experimental data, which was a considerable help in understanding the corrosion inhibition mechanism displayed by this chemical.

Experimental and computational chemical studies on the corrosion inhibitive properties of carbonitrile compounds for carbon steel in aqueous solutions

The present work aims to study 6-amino-4-aryl-2-oxo-1-phenyl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives namely: 6-Amino-2-oxo-1,4-diphenyl-1,2-dihydropyridine-3,5-dicarbonitrile (PdC-H), 6-Amino-2-oxo-1-phenyl-4-(p-tolyl)-1,2-dihydropyridine-3,5-dicarbonitrile (PdC-Me) and 6-Amino-4-(4-hydroxyphenyl)-2-oxo-1-phenyl-1,2-dihydropyridine-3,5-dicarbonitrile (PdC-OH) as corrosion inhibitors to provide protection for carbon steel in a molar hydrochloric acid medium. Chemical measurements such as (weight loss) and electrochemical techniques such as (Potentiodynamic polarization, electrochemical impedance spectroscopy, and Electron frequency modulation) were applied to characterize the inhibitory properties of the synthesized derivatives. The adsorption of these derivatives on the carbon steel surface was confirmed by Attenuated Total Refraction Infrared (ATR-IR), Atomic Force Microscope (AFM), and X-ray Photoelectron Spectroscopy (XPS). Our findings revealed that the tested derivatives have corrosion inhibition power, which increased significantly from 75.7 to 91.67% on the addition of KI (PdC-OH:KI = 1:1) to inhibited test solution with PdC-OH derivative at 25 °C. The adsorption process on the metal surface follows the Langmuir adsorption model. XPS analysis showed that the inhibitor layer consists of an iron oxide/hydroxide mixture in which the inhibitor molecules are incorporated. Computational chemical theories such as DFT calculations and Mont Carlo simulation have been performed to correlate the molecular properties of the investigated inhibitors with experimental efficiency. The theoretical speculation by Dmol3 corroborates with the results from the experimental findings.

Corrosion inhibition performance of azelaic acid dihydrazide: a molecular dynamics and Monte Carlo simulation study

The adsorption of azelaic acid dihydrazide as an environmentally friendly mild steel corrosion inhibitor on the iron surface was modeled in this study. We used density functional theory (DFT) calculations and Monte Carlo (MC) and molecular dynamics (MD) simulations to illustrate the interactions engaged. The interaction of the azelaic acid derivatives with iron metal (Fe) was examined by DFT as a typical example of a corrosion prevention mechanism after the optimized molecular structures of these molecules were investigated. Structures, binding energies, Fikui's charge indicator, electron transfer, and chemical potential are all discussed. The presence of significant binding between the inhibitor and Fe metal is supported by analysis of the resultant complex. Then, in an acidic solution comprising 491 H₂O, nine chlorine ion Cl^-, and nine hydronium ion H₃O⁺, molecular dynamics and Monte Carlo (MC) simulation were used to model the adsorption of azelaic acid dihydrazide on the iron Fe (110) surface. In addition, radial distribution function (RDF) and interaction energy (Ei) were evaluated in this work to further our understanding of interactions between azelaic acid dihydrazide and iron surfaces. Furthermore, we discovered that our inhibitors have an excellent ability to slow down the movement of corrosive particles in law temperature and thus to inhibit the metallic substrate against corrosive electrolyte, based on the temperature impact investigation. The result of density functional theory and Monte Carlo and molecular dynamics descriptors obtained were in good agreement with the experimental result.

Studies of chemical and mechanical properties of hybrid composites based on natural resin Dammar formulated by epoxy resin

Abstract

More and more importance has been given lately to the use of environment-friendly materials. Natural resins of vegetal, animal or mineral origin are increasingly employed. This article studies the properties of hybrid composites, obtained by formulating the natural resin Dammar with epoxy resin. The Dammar volume proportion was of 60%, 70% and 80%, respectively. The article is divided in two parts. In the first part, the chemical composition of the natural resin Dammar is analysed. Therefore, the substance was purified by chromatography. The structure and purity of the isolated substances were investigated by 1H-NMR, 13C-NMR experiments and mass analysis. The second part concentrates on structural characterization and on some mechanical properties of the three different hybrid composites. For this purpose, the characteristic curves, modulus of elasticity, tensile strength and elongation at break were measured.

Graphic abstract

Corrosion study of copper in aqueous sulfuric acid solution in the presence of (2E,5E)-2,5-dibenzylidenecyclopentanone and (2E,5E)-bis[(4-dimethylamino)benzylidene]cyclopentanone: Experimental and theoretical study

The corrosion behavior of copper in 0.1 M aqueous sulfuric acid medium has been studied using potentiodynamic polarization measurements, quantum chemical calculations, and molecular dynamic simulations in the presence and absence of (2E,5E)-2,5-dibenzylidenecyclopentanone (M1) and (2E,5E)-bis[(4-dimethylamino)benzylidene]cyclopentanone (M2). The compounds were freshly prepared in high yields via the Claisen–Schmidt reaction between the cyclopentanone and the corresponding aryl aldehyde. The results from the potentiodynamic measurements imply that M1 and M2 act as mixed inhibitors due to their adsorption on the copper surface. The more pronounced corrosion inhibition performance of the M2 molecule in comparison to M1 was related to the fact that this molecule contains two basic nitrogen atoms (in 4-dimethylamino group).