Inhibitor Adsorption Process Research Articles

Synthesis, structural characterization and anticorrosion properties of a new hexafunctional epoxy prepolymer based on urea and phosphorus trichloride for E24 carbon steel in 1.0 M HCl

Our goal is to set up a synthetic method to produce the hexaglycidyl amine tri-urea phosphoric acid (HGATUP), a novel hexafunctional prepolymer. We created this prepolymer by phosphorylating urea in two processes. Next, to generate the new prepolymer, we added epichlorohydrin. In addition, we focused on its microscopic characterization using FTIR and NMR. The novel HGATUP prepolymer was utilized as a corrosion inhibitor for E24 carbon steel in a 1.0M hydrochloric acid (HCl) solution. PDP, EIS, EFM, DFT, Monte Carlo (MC), and molecular dynamic (MD) simulations were used in this study. SEM/EDS and XPS studies were also used to investigate the surface morphology. These methods allowed us to examine the sample's surface characteristics and chemical composition, which added to our understanding of the adsorption along with corrosion prevention processes. The electrochemical tests' outcomes also showed that the concentration of HGATUP enhanced inhibitory performance. PDP results indicated that HGATUP at a concentration of 10-3M had a corrosion inhibition efficiency of 97.6% at 298K ambient temperature. The polarization curve confirmed that the HGATUP was a mixed type of inhibitor that could inhibit steel anodic and cathodic reactions. The Langmuir model predicted that an epoxy prepolymer protected the surface of E24 carbon steel. Calculated thermodynamic kinetic parameters were used to analyze the inhibitor adsorption processes.

Evaluation of Anti-corrosive Efficacy of Prosopis Cineraria Extract on the Nitric Acid Corrosion of Copper

Anti-corrosive propensity of Prosopis cineraria extract on the corrosion behavior of copper (Cu) in nitric acid (HNO3) medium was investigated by applying gravimetric technique. Corrosion inhibition efficiency of Prosopis cineraria was observed to enhance with increasing concentration of extract and reduce with elevation in temperature. The inhibitor underwent physisorption on the Cu metal surface. Adsorption characteristics were approximated by Langmuir adsorption isotherm. Highest inhibition efficiency (η%) 86.12 % was obtained at 303±1 K in fruit extract. It was observed that the extract acts as a benign potential corrosion inhibitor for Cu corrosion in 1.0 M HNO3 acid solution. Results revealed that existence of Prosopis cineraria extract enhances the energy of activation (Ea) of corrosion reaction. Adsorption parameters such as kinetic and thermodynamic [Gibbs free energy change (ΔG0ads) and adsorption equilibrium constant (Kads)] of adsorption process were determined from experimental data. These parameters show a strong interaction between surface of copper metal and inhibitor extract. The inhibitor adsorption process on surface of copper was found to be physical, exothermic and spontaneous. The surface morphology and characterization of copper was done by applying scanning electron microscope (SEM).

The inhibition behavior of two pyrimidine-pyrazole derivatives against corrosion in hydrochloric solution: Experimental, surface analysis and in silico approach studies

Two pyrimidine-pyrazole derivatives have been investigated as corrosion inhibitors for mild steel in acidic medium using weight loss measurement, polarization curve and electrochemical impedance spectroscopy (EIS). The results obtained reveal that these compounds perform as corrosion inhibitors for mild steel in 1 M HCl. The values of inhibition efficiency calculated from three experimental techniques are reasonably in good agreement. The adsorption process of these compounds on surface of mild steel obeys to El Awady isotherm. Also, the adsorption process of inhibitors studied explaining by surface analysis (EDX). This work followed by in silico approach studies. Firstly, we used Marvinsketch.18 program in order to detect predominant form of inhibitors in electrolytic solution and then computed by Gaussian 09 based on the DFT method at B3LYP/6-31G (d,p).The results obtained theoretically are in good correlation with those obtained experimentally.

Inhibitor adsorption processes in mild steel/new bipyrazole derivatives/hydrochloric acid system

The corrosion inhibition of mild steel in 1 M hydrochloric acid solution by some bipyrazole derivatives N,N'-dimethyl-N,N'-bis(1H-pyrazol-1-ylmethyl)ethane-1,2-diamine (3a), 1-{[{2-[[(3-carboxy-5-methyl-1H-pyrazol-1-yl)methyl](methyl)amino]ethyl}(methyl)amino]methyl}-5-methyl-1H-pyrazole-3-carboxylic acid (3b) and 1-{[{2-[{[3-(methoxycarbonyl)-1H-pyrazol-1-yl]methyl}(methyl)amino]ethyl}(methyl)amino]methyl}-1H-pyrazole-3-carboxylic acid (3c) has been studied in relation to the concentration of the inhibitors as well as the temperature using chemical (weight loss) and electrochemical (ac impedance and dc polarisation) techniques. All the methods employed are in reasonable agreement. The protection efficiency increases with increasing inhibitors concentration and with increasing temperature. The thermodynamic functions of dissolution and adsorption processes were calculated from weight loss measurement and the interpretation of the results are given. Adsorption of inhibitor on the carbon steel surface is found to obey the Langmuir adsorption isotherm.

Inhibitive effect of 4-amino-N-benzylidene-benzamide Schiff base on mild steel corrosion in HCl solution

A newly Schiff base, 4-amino-N-benzylidene-benzamide (4-BAB) protection ability was synthesised from a condensation reaction of 4-aminobenzamide (4-AB) and benzaldehyde (BA). Adsorption and corrosion inhibition effect of this compound on mild steel (MS) in 1.0 M HCl solution were studied. The data obtained from measurments of this compound were compared with that of 4-AB and BA using many electrochemical, microscopic and hydrogen gas evolution techniques to clarify superiority of the Schiff base. Some thermodynamic parameters were calculated from experimental results and discussed. The value of ΔGads showed that adsorption of 4-BAB on MS from acidic solution obeys the Langmuir adsorption isotherm model. Surface SEM images of the MS specimens which were exposed to 1.0 M HCl solution in the absence and presence of the inhibitors showed that a homogeneous and protective inhibitor film forms on the metal surface, which hinder corrosive attack. It was concluded that synthesising the Schiff base improves protection ability with respect to related amine and aldehyde and the inhibitive action is in the order of 4-BAB > 4-AB > BA.Highlights4-Amino-N-benzylidene-benzamide (4-BAB) is synthesized by condensation reaction between 4-aminobenzamide (4-AB) and benzaldehyde (BA)The inhibitor efficiencies calculated from all the applied methods are in agreement and are found to be in the order: 4-BAB >4-AB > BAThe adsorption process of inhibitors on mild steel surface obeys the Langmuir adsorption isotherm

1-(2-Hydroxyethyl)-2-imidazolidinone as corrosion inhibitor of mild steel in 0.5 M HCl solution: thermodynamic, electrochemical and theoretical studies

The inhibition effect of 1-(2-Hydroxyethyl)-2-imidazolidinone (2-HEI) on mild steel (MS) corrosion in 0.5 M HCl solution was investigated at different inhibitor concentration and temperature by electrochemical experiments, such as linear polarization resistance (LPR), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and quantum chemical calculations. The inhibitor adsorption process on mild steel in 0.5 M HCl system was studied at different temperatures (20 °C–50 °C). Furthermore, the surface morphology of MS was also investigated with SEM in the absence and the presence of inhibitor. The adsorption of 1-(2-Hydroxyethyl)-2-imidazolidinone on MS surface is an exothermic process and this process obeys the Langmuir adsorption isotherm. The Quantum chemical findings are good agreed with the empirical data.

A study of the effect of Agave Americana extract inhibitor on the corrosion of mild steel in 0.5 M H2SO4

The inhibitor effect of Agave Americana Extract (AAE), on mild steel corrosion in 0.5 M H2SO4, was investigated by potentiodynamic polarization technique and Electrochemical Impedance Spectroscopy (EIS). The inhibitor concentration effect on the corrosion process was studied. AAE acts as a mixed type inhibitor, and the inhibition efficiency increases according to the inhibitor concentration’s increase up to 81.87% at 2000 ppm. The inhibitor adsorption process is spontaneous and follows the Langmuir isotherm, as well as its molecules are both physisorbed and chemisorbed on steel surface. The inhibitor film formation was confirmed by ATR-FTIR and SEM analyses.

Inhibitive Action of New Synthesized Cationic Surfactant with Free Hydroxyl Group on the C1018 Steel Corrosion: Experimental and Theoretical Investigations

A new cationic surfactant namely, N-(2-(2-hydroxyethoxy)ethyl)-N,N-dimethylhexadecan-1-ammonium bromide (HEDHB) was prepared and its performance as a corrosion inhibitor for carbon steel in 1.0 M HCl solution was monitored by four techniques (weight loss, potentiodynamic polarization, electrochemical frequency modulation (EFM) and electrochemical impedance spectroscopy (EIS)). The temperature influence on the corrosion rate has been assessed throughout gravimetric technique. The corrosion thermodynamic and the inhibitor adsorption processes were inspected and assessed. The weight loss results confirmed that, the inhibition efficiency of the synthesized HEDHB inhibitor directly proportionally to inhibitor concentration and the temperature. Langmuir’s adsorption isotherm was the best fitted isotherm, which describes the ability of the molecule to adsorb on the steel surface. Tafel polarization reveals that the HEDHB inhibitor suppress both the anodic and cathodic reactions and thus, classified as a mixed-type inhibitor. The morphology of the treated surface with HEDHB inhibitor was monitored by two techniques (Scanning Electron Microscope (SEM) and Atomic Force Microscopy (AFM)). A quantum chemical study has been utilized to investigate the influence of molecular structure of the synthesized HEDHB inhibitor on corrosion inhibition efficiency.

Surface morphology studies and kinetic-thermodynamic characterization of steels treated in 5.0 M HCl medium: hot-dip galvanizing application

PurposeThe purpose of this paper is to study the effect of silicon and phosphorus content in steel suitable for galvanizing on its corrosion and inhibitor adsorption processes in steels/cetyltrimethylammonium bromide combined and KI (mixture)/5.0 M hydrochloric acid systems has been studied in relation to the temperature using chemical (weight loss), Tafel polarization, electrochemical impedance spectroscopy (EIS), scanning electronic microscope (SEM) analysis and Optical 3D profilometry characterization. All the methods used are in reasonable agreement. The kinetic and thermodynamic parameters for each steels corrosion and inhibitor adsorption, respectively, were determined and discussed. Results show that the adsorption capacity for Steel Classes A and B are better than Steel Class C surfaces depending on their silicon and phosphorus content. Surface analyses via SEM and Optical 3D profilometry was used to investigate the morphology of the steels before and after immersion in 5.0 M HCl solution containing mixture. Surface analysis revealed improvement of corrosion resistance of Steels Classes A and B in the presence of mixture more than Classes C. It has been determined that the adsorbed protective film on the steels surface heterogeneity markedly depends on steels compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.Design/methodology/approachThe effect of silicon and phosphorus content in Steels Classes A, B and C on its corrosion and inhibitor mixture adsorption processes in 5.0 M HCl solution has been studied by weight loss, potentiodynamic polarization, EIS and surface analysis.FindingsThe inhibition efficiency of mixture follows the order: (Steel Class A) > (Steel Class B) > Steel Class C) and depends on their compositions in the absence of mixture according on their silicon and phosphorus content, that is, the corrosion rate increases with increasing of the silicon and phosphorus content. A potentiodynamic polarization measurement indicates that the mixture acts as mixed-type inhibitor without changing the mechanism of corrosion process for the three classes of mild steels.Originality/valueCorrosion rate mild steels in 5.0 M HCl depends on their compositions in the absence of mixture according to their silicon and phosphorus content, that is, the corrosion rate increases with increasing silicon and phosphorus content. The adsorbed protective film on the steels surface heterogeneity markedly depends on steels class’s compositions, that is, the heterogeneity increases with decreasing silicon and phosphorus content.

Thermodynamic Characterization of Metal Dissolution and Inhibitor Adsorption Processes in Mild Steel/New Bipyrazole Derivatives/Hydrochloric Acid System

Thermodynamic Characterization of Metal Dissolution and Inhibitor Adsorption Processes in Mild Steel/New Bipyrazole Derivatives/Hydrochloric Acid System

Adsorption and precipitation of scale inhibitors on shale formations

Abstract Scale inhibitor is one of the most important ingredients in hydraulic fracturing fluids for shale gas production. However, the adsorption and precipitation behaviors of scale inhibitors on shale formations have never been reported. The objective of this study is to develop mechanistic understanding of interactions between common scale inhibitors and shale formations so that we can predict the fate and transport of scale inhibitors in shale formations. The adsorption and precipitation of DTPMP and PPCA on Eagle Ford and Marcellus shales were studied in batch reactors at oil field temperature of 70 °C. The adsorption kinetics shows a fast adsorption process of inhibitors on shales, and inhibitor concentrations reach equilibrium between 4 and 8 h. In batch adsorption isotherm experiments, initial concentrations of scale inhibitors in aqueous phase varied from 5 ppm to 44,000 ppm. At low DTPMP concentration ranges, surface adsorption occurs on both Eagle Ford and Marcellus. Above certain concentrations, DTPMP and calcium forms precipitate on Eagle Ford, which increases the attachment, and slightly acidic pH and high calcium concentrations enhance the precipitation. The adsorption of PPCA on Eagle Ford was more significant at slightly acidic conditions, and PPCA adsorption onto Marcellus did not exhibit a notable difference between different pH conditions. Due to the strong chelating effect of DTPMP and PPCA, iron was extracted from Marcellus under high inhibitor concentrations.

Electrochemical, gravimetric and quantum chemical analysis of mild steel corrosion inhibition by colchicine in 1 M HCl medium

The inhibition effect of colchicine (CC) on mild steel (MS) corrosion in 1 M HCl solution has been investigated by electrochemical techniques such as electrochemical impedance spectroscopy, potentiodynamic polarization, chronoamperometry and also by the gravimetric method. Polarization studies showed that CC acts as mixed type corrosion inhibitor. The inhibitor adsorption process in the MS/CC/HCl system was studied at different temperatures (303–333 K). The adsorption of CC on MS surface is an exothermic process and obeys the Langmuir adsorption isotherm. Based on potential of zero charge values and quantum chemical parameters, the mechanism of adsorption has been proposed.

Corrosion Inhibition of Aluminum in 0.1M HCL by <i>Ne</i><i>phelium </i><i>la</i><i>ppaceum</i> (Rambutan) Peel Extract

Corrosion control of metals is about technical, economic, environmental, and aesthetic importance. Synthetic corrosion inhibitors are toxic to environment and human life. Thus, the searches for natural corrosion inhibitors are essential as they are biodegradable and non toxic. The purpose of this study is to investigate the ability ofNephelium lappaceumpeel extract as a corrosion inhibitor of aluminum in 0.1M HCl solutions. Obtained data from gravimetric and thermometric analysis has shown the value of inhibition efficiency (% IE) is proportional to added inhibitor concentration and inversely proportional to the temperature. Occurred inhibition mechanism was in the form of inhibitor adsorption process on aluminum surface that allegedly preceded by physical adsorption. The SEM study also confirmed there were adsorptions of extracted inhibitor molecules onto aluminum surface. Therefore, from the observational results obtained, it can be concluded thatNephelium lappaceumpeel extract was an attractive candidate for the natural corrosion inhibitor.

Application of Myrmecodia Pendans Extract as a Green Corrosion Inhibitor for Mild Steel in 3.5% NaCl Solution

The use of Myrmecodia Pendans (MP) extract as mild steel corrosion inhibitor in 3.5% NaCl media was investigated using weight loss and potentiodynamic polarization methods as well as characteristics analysis of the Fourier Transform Infra-Red (FTIR). Obtained data from weight loss and potentiodynamic polarization methods has shown the value of inhibition efficiency (% IE) is proportional toadded inhibitor concentration. Tafel constants data indicates that MP extract can act as cathodic and anodic inhibitors (type of mixed inhibitor). FTIR analysis also demonstrates the characteristics of MPextract. Occured inhibition mechanism was in the form of inhibitor adsorption process on metal surfacethat allegedly preceded by physical adsorption followed by chemical adsorption. Chemical adsorption is conceivable since metal surface scoping elevates as the increasing of inhibitor concentration.

Inhibition Effects on the Corrosion of Mild Steel in 1 M HCl by 1,1'-(2,2'-(2,2'-oxybis(ethane-2,1-diyl)bis(sulfanediyl)) bis(ethane-2,1-diyl))diazepan-2-one

The inhibition of the corrosion of Mild Steel (MS) in 1 M HCl solution by a new synthesised organic compound, namely 1,1'-(2,2'-(2,2'-oxybis(ethane-2,1-diyl)bis (sulfanediyl))bis(ethane-2,1-diyl))diazepan-2-one, has been studied by weight loss measurements, electrochemical polarisation and electrochemical impedance spectroscopy (EIS). The experimental results have showed that this organic compound revealed a good corrosion inhibition and the inhibition efficiency is increased with the inhibitor concentration to reach 97% at 1 mM. Potentiodynamic polarisation suggested that it is a mixed type of inhibitor. EIS measurements show an increase of the polarisation resistance with the inhibitor concentration and the electrical equivalent circuit is determined. The inhibitor adsorption process on (MS) surfaces obeys the Langmuir adsorption isotherm and the adsorption isotherm parameters (K ads , �Gads ,

Inhibitive Properties and Adsorption of Purpald as a Corrosion Inhibitor for Copper in Nitric Acid Medium

Inhibition performance of purpald (4-amino-3-hydrazino-5-mercapto-1,2,4-triazole (AHMT)) was investigated as a corrosion inhibitor for a copper surface in 2 M HNO3 at 303 K by weight loss, ac impedance, and dc polarization techniques. The obtained results indicate that AHMT is a good inhibitor and its inhibition efficiency attains 94.7% at 10–2 M. Polarization studies showed that AHMT acts as a mixed type inhibitor. The inhibitor adsorption process in the Cu/AHMT/2 M HNO3 system was studied at different temperatures (303–343 K). The adsorption of AHMT on the copper surface obeyed Langmuir’s adsorption isotherm. The kinetic and adsorption parameters for copper/acid in the presence and absence of AHMT were evaluated and discussed.

Enhancement of corrosion protection efficiency of mild steel by 3,5-di(4-tolyl)-4-amino-1,2,4-triazole in hydrochloric acid medium

New 3,5-disubstituted-4-amino-1,2,4-triazole derivative, namely 3,5-di(4-tolyl)-4-amino-1,2,4-triazole (4-DTAT) was synthesised and its inhibitive action against the corrosion of mild steel in 1 M HCl solution was investigated at 308 K. The detailed study of 4-DTAT was been performed using gravimetric measurements and polarisation curves method. Results show that 4-DTAT is a good inhibitor and its inhibition efficiency reaches 95 % at·10 −4 M. Tafel polarisation study revealed that 4-DTAT acts as a mixed type inhibitor. The adsorption of 4-DTAT on steel surface obeyed Langmuir’s adsorption isotherm. The inhibitor adsorption process in mild steel/4-DTAT/hydrochloric acid system was studied at different temperatures (308-323 K) by means of weight loss measurements.

Thermodynamic study of metal corrosion and inhibitor adsorption processes in copper/N-1-naphthylethylenediamine dihydrochloride monomethanolate/nitric acid system: part 2

N-1-Naphthylethylenediamine dihydrochloride monomethanolate (N-NEDHME) was tested as a corrosion inhibitor for copper in 2 M HNO3 solution using the standard gravimetric technique at 303–343 K. N-NEDHME acts as an inhibitor for copper in an acidic medium. Inhibition efficiency increases with increase in concentration of N-NEDHME but decreases with a rise in temperature. Thermodynamic parameters such as adsorption heat (\( \Updelta H_{\text{ads}}^\circ \)), adsorption entropy (\( \Updelta S_{\text{ads}}^\circ \)) and adsorption free energy (\( \Updelta G_{\text{ads}}^\circ \)) were obtained from experimental data of the temperature studies of the inhibition process at five temperatures ranging from 303 to 343 K. Kinetic parameters activation such as \( E_{a} \), \( \Updelta H_{\text{a}}^\circ \), \( \Updelta S_{\text{a}}^\circ \) and pre-exponential factors have been calculated and are discussed. Adsorption of N-NEDHME on the copper surface in 2 M HNO3 follows the Langmuir isotherm model.

N-Aminorhodanine as an effective corrosion inhibitor for mild steel in 0.5 M H 2SO 4

The corrosion inhibition effect of N-aminorhodanine ( N-AR) on mild steel (MS) in 0.5 M H 2SO 4 was studied in both short and long immersion duration using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), chronoamperometry and hydrogen gas evolution. The surface morphology of MS was examined with scanning electron microscopy (SEM) in absence and presence inhibitor. The inhibitor adsorption process on MS surfaces obeys the Langmuir adsorption isotherm. The results show that NAR is a good inhibitor for MS in the acidic medium. The inhibition efficiency obtained from potentiodynamic polarization, EIS and LPR up to 98% is determined.

Adsorption properties and inhibition of mild steel corrosion in hydrochloric solution by some newly synthesized diamine derivatives: Experimental and theoretical investigations

New diamine derivatives, namely 2-[{2-[bis-(2-hydroxyethyl)amino]ethyl}(2-hydroxyethyl)amino]ethanol (DAME) and 2-[{2-[bis-(2-hydroxyethyl)amino]ethyl}(2-hydroxyethyl)amino]propanol (DAMP) were synthesised and their inhibitive action against the corrosion of mild steel in 1 M HCl solution were investigated at 308 K. The detailed study of DAME is given using gravimetric measurements and polarization curves method. Results show that DAME is a good inhibitor and inhibition efficiency reaches 91.7% at 10 −3 M. Tafel polarization study revealed that DAME acts as a mixed-type inhibitor. The inhibitor adsorption process in mild steel/DAME/hydrochloric acid system was studied at different temperatures (308–353 K) by means of weight loss measurements. The adsorption of DAME on steel surface obeyed Langmuir’s adsorption isotherm. The kinetic and thermodynamic parameters for mild steel corrosion and inhibitor adsorption, respectively, were determined and discussed. The comparative study of inhibitive performance of the two diamine derivatives revealed that DAME is more effective than DAMP. Quantitative Structure–Activity Relationship (QSAR) approach has been conducted in attempt to correlate the corrosion inhibition properties of these diamine derivatives with their calculated quantum chemical parameters.