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Abstract Nine phosphonates surfactant were synthesized by two steps. The first step was condensation between acetaldehyde and butyl amine, dodecylamine or hexadecylamine individually to give three corresponding Schiff bases, and then the Schiff base products were added to dibutyl phosphite individually. The second step was reaction of the phosphonate products with polyethylene glycol 400, 600 and 1000 to get on the nine water soluble phosphonate corrosion inhibitors. The products were characterized by FTIR, 1HNMR and 13CNMR spectroscopic techniques. The surface active properties of this phosphonate were calculated and they were evaluated as corrosion inhibitors in formation water formulations using open circuit potential and potentiodynamic polarization. The quantum calculations of the structures were calculated and the data obtained were nearly closed with the experimental data. HMPA1 shows the best results as corrosion inhibitors (efficiency 94%) at lowest concentration 15 ppm. The corrosion inhibition mechanism was discussed on the basis of surface tension measurements and the electronic data. Graphical abstract Unlabelled Image Highlights • Nine novel phosphonates were synthesized and characterized by spectroscopic methods. • Electrochemical techniques were used to evaluate as corrosion inhibitors. • Quantum was applied to the synthesized phosphonate to predict their efficiencies. • The percentage inhibition efficiency (IE%) of the surfactants increases by decrease the alkyl chain and the ethylene units. [ABSTRACT FROM AUTHOR]

Abstract Recovery shrimp waste protein (RSWP) was extracted, characterized and tested their inhibition effects as a corrosion inhibitor for carbon steel in 1 M HCl solution using different electrochemical techniques. The results have been shown that the corrosion rate decreases with increasing inhibitor concentration. To verify the morphology of RSWP film formed on the carbon steel surface, scanning electron microscopy (SEM) was used. The inhibition mechanism of the extracted RSWP is discussed in terms of adsorption on the carbon steel surface. The results of the energy adsorption were showed chemisorption effect for RSWP on the carbon steel surface. [ABSTRACT FROM AUTHOR]

Abstract A newly anionic surfactant; namely (2Z,2′Z)-4,4′-(ethane-1,2-diylbis((2-((4-dodecylphenyl)sulfonamido)ethyl)azanedinyl)bis(4-oxobut-2enoate), desined as Tetra-anionic surfactant was synthesized. Its chemical structure was confirmed by FTIR and 1HNMR spectroscopic techniques. The corrosion mitigation behavior of the prepared surfactant for mild steel (MS) in high saline synthetic water was monitoring by chemical technique (weight loss), electrochemical techniques (Tafel and EIS). The obtained results showed that the corrosion resistance has been improved after the addition of the surfactant molecules. The inhibition efficiency grown up with the inhibitor concentration reaching the maximum at concentration 120 ppm, where the IE% values were 84, 82, and 79.5% in cases of weight loss, Tafel and EIS techniques, respectively. The mixed-type inhibitor with permanent anodic effect can be inferred from polarization data of mild steel in the presence of different concentration of Tetra- compound. The corrosion protection performance of the used inhibitor was related to its adsorption ability on the MS surface. The adsorption of Tetra-molecules increased the charge transfer resistance of MS. The adsorption process of the tested corrosion inhibitor obeyed Langmuir adsorption isotherm. The corrosion and scale produced layer formed on the mild steel surface in absence and presence of the insight anionic surfactant was depicted by SEM. The chemical analysis of this layer was examined by EDX, and show the corrosion and Ca- scale inhibition performance of Tetra- molecules. Quantum chemical calculations were compatible with the experimental results. [ABSTRACT FROM AUTHOR]

Graphical abstract The suggested corrosion protection mechanism of cured ilmenite epoxy. Highlights • Upgrading the added value of Egyptian ilmenite ore to be used as a bi-functional modifier. • Tafel lines were performed to study the anticorrosion behavior of ilmenite epoxy. • Abrasion resistance of polyamine cured ilmenite epoxy coating was studied. Abstract To uphold the corrosion protection of oil and gas steel tanks in petroleum sector, different high build epoxy coating formulations cured by polyamine hardener were modified by incorporation various concentrations of processed micro-sized ilmenite particles (FeTiO 3) obtained by a solid phase milling process as a pigment to form a highly cross linked ilmenite epoxy adduct in three dimensional network. The lamellar shape of micro-sized ilmenite particles was emphasized by transmission electron microscopy (TEM) investigation. Flaky-like nature and the arrangement in overlapping plates of ilmenite particles were characterized by scanning electron microscopy (SEM) micrographs. The electrochemical behavior of cured ilmenite epoxy coated steel films against unmodified conventional epoxy in oil-wells formation water has been studied by potentiodynamic polarization measurements. From the obtained electrochemical results for the coated steel films it was found that, the maximum performance was exhibited at 100% treatment of the processed ilmenite ore at which the corrosion current (I cor r) was less than the value 15 nA·cm−2 and exhibited the highest value of the protection efficiency (η) 99%. Cure durability test was implemented for appreciation the organic solvents resistance of the investigated cured coated films to confirm their application efficiency. The recorded data ensured the improvement in cure resistance with increasing the amount (%) by weight of micro-sized ilmenite particles against softening, wrinkling and loss of adhesion in case of unmodified conventional cured epoxy. Accelerated ultra violet (UV) exposure coating test was accomplished to measure the ability of the cured coated films to resist UV weathering and sun light damage. From the obtained exposure results it was found that, there is no blistering, no rust, no cracking, no flaking and no loss in adhesion in addition to the glossy variation at 60° was from 22.9° to 21.65° in case of the cured ilmenite epoxy coated films against complete deterioration in the film properties of conventional unmodified cured epoxy. The abrasion test was performed to determine the scraping resistance of the cured coated films. The results indicated that, there is a decrease in the weight loss of the coated films as a function of abrasion resistance with increasing the loading level (%) by weight of ilmenite pigment. [ABSTRACT FROM AUTHOR]

A new family of nonionic surfactants was synthesized and evaluated as corrosion inhibitors for steel pipelines in oil well formation water. Polarization data show that the selected surfactants act as mixed-type inhibitors. EIS results show that the change in impedance parameters (Rt and Cdl) with the concentration of the surfactants studied is indicative of the adsorption of surfactant molecules on carbon steel surface, leading to formation of a good protective film. The properties of this film were studied by various surface analysis tools. Finally, the relation between the surface properties of the inhibitor molecules and corrosion inhibition efficiency is discussed. [ABSTRACT FROM AUTHOR]

Abstract: The synergistic inhibition effect between Cu2+ and cationic gemini surfactant namely; 1,2-ethane bis(N,N-dimethylhexadecylammonium bromide); on the corrosion behavior of downhole tubing steel during secondary oil recovery of old wells was investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The results revealed that Cu2+ and cationic gemini surfactant mixture had a good inhibitive effect on the corrosion of carbon steel in produced water from the oil well. The surface parameters of surfactant were calculated from surface tension measurements at the air–water interface. The nature of protective film formed on steel surface was studied using EDX and SEM. [Copyright &y& Elsevier]

In this work, a new polyamide (PA) based on thiourea and tartaric acid was synthesized and characterized by FT-IR spectroscopy. The efficiency of the new synthesized compound was evaluated as a corrosion inhibitor for carbon steel in 1 M HCl solution using weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques (EIS). The results show that PA is a good corrosion inhibitor and its inhibition efficiency reaches 90.6% at 250 ppm. The values of the inhibition efficiency calculated from various techniques are in reasonably good agreement. The results obtained from EIS measurements show that the charge transfer resistance (Rt) increases with increasing inhibitor concentration, while the electrochemical double layer capacitance (Cdl) decreases. The inhibition process was attributed to the formation of an adsorbed film that protects the metal surface against corrosive medium. The adsorption of PA on the steel surface was found to obey Langmiur's adsorption isotherm. The mechanism of the adsorption process was discussed in the light of the chemical structure of PA. Scanning electron microscopy (SEM) and energy dispersive analysis of X-ray (EDX) were used to confirm the existence of such protective film. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the dodecyl cysteine hydrochloride surfactant was synthesized. The surface properties of this surfactant were studied using surface tension technique. The nanostructure of this surfactant with the prepared gold nanoparticles was investigated using TEM technique. The synthesized surfactant and its nanostructure with the prepared gold nanoparticles were examined as non-toxic corrosion inhibitors for carbon steel in 2M HCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The results show that the percentage inhibition efficiency (η%) for each inhibitor increases with increasing concentration until critical micelle concentration (CMC) is reached. The maximum inhibition efficiency approached 76.6% in the presence of 175ppm of dodecyl cysteine and 90.8% in the presence of the same concentration of dodecyl cysteine hydrochloride self-assembled on gold nanoparticles. Polarization data indicate that the selected additives act as mixed type inhibitors. The slopes of the cathodic and anodic Tafel lines (β c and β a) are approximately constant and independent of the inhibitor concentration. Analysis of the impedance spectra indicates that the charge transfer process mainly controls the corrosion process of carbon steel in 2M HCl solution both in the absence and presence of the inhibitors. Adsorption of these inhibitors on carbon steel surface is found to obey the Langmuir adsorption isotherm. From the adsorption isotherms the values of adsorption equilibrium constants (K ads) were calculated. The relatively high value of (K ads) in case of dodecyl cysteine hydrochloride self-assembled on gold nanoparticles reveals a strong interaction between the inhibitor molecules and the metal surface. [Copyright &y& Elsevier]

Twelve new ethoxylated mono alkyl bisphenol surfactants were prepared. These surfactants have a general formula as E(X) B(Y) M(R) wherein, the E(X) is the degree of ethylene oxide units, the B(Y) is the bisphenol which based on acetophenone (BAC), cyclohexanone (BCH), or acetone (BA) and R is the alkyl chain of fatty acids (decanoic, lauric, myristic, palmitic, stearic, oleic, linoleic, or linolinic). The chemical structures were confirmed using FTIR. The surface active properties for these surfactants were calculated using surface tension measurements. They were tested as corrosion inhibitors for carbon steel alloy in 2 M HCl solution the inhibition efficiency was evaluated using potensiostate Wenking 81 M. The efficiency of inhibitors was discussed on the light of their chemical structures such as alkyl chain length, degree of unsaturation, ethoxylation, bisphenol skeleton, and structure modification. From the data obtained it was found it was found that a strong relation between the surface active properties and the corrosion inhibition efficiency, also, the results clear that the corrosion inhibition efficiency increases with increasing the degree of unsaturation, ethoxylation, and alkyl chain length. Regarding to the bisphenol skeleton, it was noticed that the minimum inhibition efficiency was exhibited by bisphenol BCH, but the maximum efficiency was obtained by bisphenol BAC. As a result of these parameters, the 87.68% corrosion inhibition efficiency was obtained by inhibitor E(43) BCHMLL and 93.32% efficiency was exhibited by E(43) BACMLL. [ABSTRACT FROM AUTHOR]

Abstract: The ability of new synthesized non ionic surfactants (I and II) to protect carbon steel in acid chloride solution was investigated using potentiostatic polarization, open circuit potential, weight loss and surface tension measurements. The experimental results showed that these inhibitors revealed a very good corrosion inhibition even at low concentrations. The percentage inhibition efficiency (η%) increases by increasing the inhibitor concentration until the critical micelle concentration (cmc) is reached. It was found that, the adsorption ability of the surfactant molecules on carbon steel surface increased with the increase of the molecular size of the surfactant. Potentiostatic polarization curves indicate that the inhibitors under investigation act as mixed type. Finally, the mechanism of carbon steel dissolution in acidic medium was discussed both in absence and presence of the inhibitor molecules. [Copyright &y& Elsevier]

The present work investigated the preparation of valine of polyaspartic acid (Val-PASP) and leucine of poly aspartic acid (Leu-PASP) by using polysuccinimide. PASP compounds were used as corrosion and scale inhibitors. The prepared derivatives in this study were characterized by using Fourier transform infrared spectroscopy and nuclear magnetic resonance 1HNMR. The electrochemical behavior of the synthesized compounds was studied on carbon steel surface using potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The morphology of the C-steel specimens was surveyed using scanning electron microscopy and energy dispersive analysis of X-rays investigations. Scale agglomeration inhibition was evaluated using different concentrations of the inhibitors using standard scale test method. The highest corrosion inhibition efficiency for Val-PASP and Leu-PASP reaches 86.94 and 88.62% respectively at 250 ppm concentration, while their scale inhibition efficiency reaches 92.3 and 94.1% respectively at 125 ppm concentration. [ABSTRACT FROM AUTHOR]

Abstract: Four Gemini surfactants were synthesized and characterized using elemental analysis, FTIR and 1H NMR spectroscopy. The synthesized compounds were evaluated as corrosion inhibitors for carbon steel in 0.5M HCl solution. The inhibition efficiencies of the tested inhibitors were depended on the hydrophobic chain length and the used doses of the inhibitors. The polarization measurements showed that these inhibitors are acting as mixed inhibitors for both anodic and cathodic reactions. The results showed that the inhibition efficiencies were increased by increasing the inhibitor doses and the hydrophobic chain length and reached the maximum at 500ppm by weight for stearyl derivative. The efficiencies obtained from the impedance measurements were in good agreement with those obtained from the gravimetrical and polarization techniques which prove the validity of these tolls in the measurements of the tested inhibitors. [Copyright &y& Elsevier]