Cationic surfactant based on alignate as green corrosion inhibitors for the mild steel in 1.0 M HCl

Three cationic surfactants based on alginic acid were laboratory prepared. These compounds were evaluated as corrosion inhibitors utilizing three techniques, namely; weight loss, polarization and electrochemical impedance spectroscopy. The corrosive medium was 1.0?M HCl. The corrosion rate of mild steel in 1.0?M HCl at four different temperatures 25, 40, 55 and 70?°C was investigated gravimetrically. The corrosion rate of mild steel was confirmed electrochemically at 25?°C. It was found that the corrosion inhibition efficiency directly proportionally with the hydrophobic chain length of synthesized inhibitors and also with the plethora of concentration. The inhibition efficiency exhibit a positive trend with raising the solution temperatures as indication for chemisorption. The potentiostatic polarization study revealed that the tested green cationic surfactants act as mixed type inhibitors with predominant control of cathodic reaction. The decreasing in the double layer capacitance obtained from electrochemical impedance measurements refer to increasing the thickness of the formed double layer. The apparent activation energy of the inhibited solution was found to be lower than uninhibited solution as an indication for chemical adsorption.     

Evaluation of a novel cationic surfactant based on 2-(2 (dimethylamino)ethoxy)ethanol as a corrosion inhibitor for carbon steel 1018 in 1.0 M HCl solution

Corrosion inhibition of a novel cationic surfactant namely, N-(2-(2-hydroxyethoxy)ethyl)-N,N-dimethyldodecan-1-aminium bromide (HEDDB) was evaluated as a corrosion inhibitor for carbon steel in 1.0 M HCl by electrochemical frequency modulation (EFM), potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. Results of Tafel polarization exhibit that the synthesized surfactant HEDDB behaves as mixed-type inhibitor. The effectiveness of temperature on the corrosion rate which evaluated by chemical technique (weight loss) was investigated and assessed. Langmuir’s adsorption isotherm was the preferable fitted isotherm. The results of weight loss clarified that the efficiency of the synthesized surfactant increases with raising both the concentration of the surfactant and the temperature. HEDDB effectiveness on the morphology of metal surface was monitored by Atomic Force Microscopy (AFM) and Scanning Electron Microscope (SEM) techniques. Quantum chemical technique has been employed to discuss the inhibition efficiency by effectiveness of molecular structure of the synthesized inhibitor. The various techniques which used in this research have inhibition efficiency (IE) with the same direction.     

新型苄叉丙酮曼尼希碱缓蚀剂的合成及其缓蚀性能研究

以苄叉丙酮、苯甲醛、氨基硫脲为原料合成曼尼希碱缓蚀剂,采用静态失重法、极化曲线法、电化学阻抗谱法(EIS)等方法研究了其在盐酸介质中对N80钢的缓蚀行为.结果表明:在60℃、10％HCl溶液中加入1％ 缓蚀剂,N80钢的腐蚀速率为0.7471 g/(m2·h);极化曲线表明该缓蚀剂为混合型缓蚀剂;缓蚀剂在钢表面的吸附遵...     

The performance of hydrophobic and hydrophilic moieties in synthesized thiol cationic surfactants on corrosion inhibition of carbon steel in HCl

Here in, cationic surfactants namely (1-octyl, decyl, and dodecyl-4-mercaptopyridine-1-ium bromide) I, II and III, respectively, were synthesized. The inhibition effect of these surfactants on the corrosion of carbon steel in 1 M HCl was studied by polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. Polarization curves revealed that the used inhibitors represent mixed-type inhibitors. Adsorption of used inhibitors led to a reduction in the double layer capacitance and an increase in the charge transfer resistance. Adsorption of used compounds was found to obey Langmuir isotherm.     

喹啉与硫脲在含饱和CO_2气井采出水中的协同效应

加注缓蚀剂抑制CO_2腐蚀是天然气开发过程中的常见工艺,利用缓蚀协同效应可以有效降低缓蚀剂的用量,减少对环境的污染,提高经济效益。为此,采用静态失重法、电化学极化曲线、阻抗谱(EIS)、扫描电子显微镜(SEM)及电子能谱等实验分析方法,研究了在含饱和CO_2模拟气井采出水腐蚀体系中,喹啉季铵盐(QN)与硫脲(TU)对N80碳钢的缓蚀协同效应。结果表明:①喹啉季铵盐和硫脲均能有效抑制N80碳钢的腐蚀;②喹啉季铵盐是一种以抑制阴极型为主的缓蚀剂;③硫脲对N80碳钢的阴极和阳极均具有较强的抑制作用,是一种混合型缓蚀剂;④当喹啉季铵盐与硫脲复配使用时,在较低的使用浓度下,喹啉季铵盐缓蚀剂与硫脲具有较好的缓蚀协同效应,当3 mg/L喹啉季铵盐缓蚀剂与7 mg/L硫脲复配使用时,缓蚀效果最佳,缓蚀率可达到93.59%;⑤喹啉季铵盐与硫脲相互作用在N80碳钢表面能形成稳定的吸附膜,较大程度地抑制N80碳钢的腐蚀过程。进而还对喹啉季铵盐与硫脲之间的协同作用机理进行了探讨。     

Surface protection of mild steel in acidic chloride solution by 5-Nitro-8-Hydroxy Quinoline

The effect of commercially available quinoline nucleus based pharmaceutically active compound 5-Nitro-8-Hydroxy Quinoline (NHQ) against the corrosion of mild steel (MS) in 1 M acidic chloride (HCl) solution was investigated by chemical (weight loss – WL) and electrochemical (Tafel polarization, Linear polarization and Electrochemical impedance spectroscopy) techniques. From all the four methods, it is inferred that the percentage of inhibition efficiency increases with increasing the inhibitor concentration from 50 to 300 ppm. The adsorption behavior of inhibitor obeyed through Langmuir isotherm model. Thermodynamic parameters were also calculated and predict that the process of inhibition is a spontaneous reaction. EIS technique exhibits one capacitive loop indicating that, the corrosion reaction is controlled by charge transfer process. Tafel polarization studies revealed that the investigated inhibitor is mixed type and the mode of adsorption is physical in nature. The surface morphologies were examined by FT-IR, SEM and EDX techniques. Theoretical quantum chemical calculations were performed to confirm the ability of NHQ to adsorb onto mild steel surface.     

Magnetite nanoparticles/polyvinyl pyrrolidone stabilized system for corrosion inhibition of carbon steel

The corrosion inhibitive effects of new polyvinylpyrrolidone stabilized crystalline super-paramagnetic nanoparticles (5–20?nm) were investigated. Several characterization techniques confirmed the high stability of the prepared stabilized nanoparticles in solution. The polarization and EIS measurements showed that the inhibition efficiency increased with increasing concentration of the magnetite nanoparticles. The results obtained from EIS and electrochemical polarization curves are in reasonably good agreement. The obtained results suggest that the prepared stabilized system is an excellent inhibitor for carbon steel corrosion in 1?M HCl solution.     

Phytochemical screening and corrosion inhibitive behavior of Pterolobium hexapetalum and Celosia argentea plant extracts on mild steel in industrial water medium

Preliminary phytochemical screening was carried out for methanolic extracts of Pterolobium hexapetalum (PH) and Celosia argentea (CA). Methanolic extracts of PH and CA were studied as corrosion inhibitors for mild steel in industrial water medium using mass loss and electrochemical techniques. The adsorption of both PH and CA extracts on mild steel surface followed Langmuir isotherm. The electrochemical impedance spectroscopy (EIS) measurements showed that the charge transfer resistance increases with increasing concentration of extracts. Various thermodynamic parameters were evaluated and discussed. Scanning electron microscopy (SEM) was used to analyze the surface adsorbed film. Further, antioxidant activity of the plant extracts was determined and correlated with the results obtained with inhibition efficiency.     

新型油酸基咪唑啉酰胺对A3碳钢的缓蚀性能研究

针对高酸原油加工中分馏塔顶循环回流（简称顶循）系统腐蚀加剧的现状,对自合成的新型油酸基咪唑啉酰胺（EYP）的缓蚀性能进行了研究。采用失重法评价缓蚀剂EYP在模拟顶循油体系中的缓蚀性能,考察了EYP的添加量和腐蚀体系温度对其缓蚀效率的影响,并采用电化学方法对缓蚀机理进行了探讨,采用SEM对碳钢表面的腐蚀形貌进行了分析。结果表明：EYP在顶循油模拟体系中对A3碳钢具有优良的缓蚀性能;随着腐蚀体系中EYP添加量的增大,缓蚀效率先增大然后略有降低;温度对EYP的缓蚀效率影响较小,随着温度升高,EYP的缓蚀效率略有降低; EYP在金属表面的吸附包括化学吸附和物理吸附,呈一种有序化的状态;EYP是一种能同时抑制阴极和阳极反应的高效“混合型缓蚀剂”。     

Adsorption and inhibition behavior of a novel Schiff base on carbon steel corrosion in acid media

In this study, the inhibition effect of 2,2′-(heptane-1,7-diylbis(azanylylidene)bis-(methanylylidene))diphenol (HAMD) on carbon steel corrosion in 0.5 mol L⁻¹ H₂SO₄ solution was studied. Weight loss and electrochemical techniques such as open circuit potential (OCP), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were used to inspect the efficiency of HAMD as corrosion inhibitor. Scanning electron microscopy (SEM) and energy dispersion X-ray (EDAX) were used to characterize the steel surface. Polarization measurements indicated that, the studied inhibitor acts as mixed-type inhibitor. The adsorption of HAMD molecules on the carbon steel surface obeys Langmuir adsorption isotherm.     

Effectiveness of a fish scales-derived chitosan coating for corrosion protection of carbon steel

Many naturally-derived organic coating has been proposed for corrosion protection of carbon steel, but its effectiveness is challenged by poor coating adhesion. In this work, chitosan was extracted from Nila tilapia fish scales and coated onto ASTM A36 carbon steel surface by using electrophoretic deposition (EPD) and dip coating (DC) techniques. The work aims at determining the coating technique and process parameters that result in effective corrosion protection of carbon steel in acid solution. The effectiveness of corrosion protection was determined by calculating inhibition efficiency from corrosion parameters obtained by polarization test and electrochemical impedance spectroscopy. Results showed that each coating technique provides different mechanism of corrosion protection. The DC-made coating showed a physisorption mechanism where the steel's corrosion rate increases as the temperature increased. The EPD-coated specimens demonstrated a chemisorption mechanism with its minor change in corrosion rates than those of DC-coated specimens. The DC technique resulted in a higher inhibition (73 %) efficiency and lower corrosion rate than that of EPD (41 %) with some degree of stability over increasing temperature.     

Influence of copper nanoparticles capped by cationic surfactant as modifier for steel anti-corrosion paints

The synthesized cationic surfactant N-(2-(2-mercaptoacetoxy) ethyl)-N,N-dimethyldodecan-1-aminium bromide (QSH) was used to prepare colloidal copper nanoparticles (CuNPs) in water through the chemical reduction method. The obtained copper nanoparticles were characterized by FTIR spectrum and transmission electron microscopy (TEM). The corrosion performance was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements in addition to the salt spray test. The results obtained from these methods were in good agreement. Results showed that the modified coating provide a good coverage and an additional corrosion protection of the carbon steel.     

土壤中阴离子对碳钢腐蚀的影响

用弱极化曲线技术和交流阻抗法研究了土壤中Cl-,SO42-,CO32-,NO3-对碳钢腐蚀的影响。结果表明:阴离子对碳钢腐蚀的影响比较显著。当土壤中分别添加Cl-,CO32-,NO3-时,随着阴离子质量浓度的增加,碳钢的腐蚀速率增大,在某一离子质量浓度时,腐蚀速率达到最大,然后腐蚀速率随着离子质量浓度的增加而减小。在有SO42-的土壤中随着SO42-质量浓度的增大,土壤中碳钢的腐蚀速率增大。在四种阴离子土壤中,阻抗谱均为单容抗弧,且大多在低频区出现扩散弧。     

The Synthesis and Evaluation of N-carbonyl Piperazine as a Hydrochloric Acid Corrosion Inhibitor for High Protective 13Cr Steel in an Oil Field

Abstract

A new inhibitor—N-carbonyl piperazine aimed at anticorrosion of high protective 13Cr steel was synthesized by electrochemistry together with ionic liquid. Its molecule structure was analyzed by gas chromatography/mass spectrometry and infrared spectroscopy. On that base, the inhibition mechanism of N-carbonyl piperazine on the corrosion of high protective 13Cr steel in 4 M HCl had been studied by polarization, electrochemical impedance spectroscopy, weight loss, and scanning electron microscopy measurements. The results indicated that N-carbonyl piperazine acted as mixed type (cathodic/anodic) inhibitor and showed 93.7% inhibition efficiency at concentration of 44 mM.     

Gemini表面活性剂的缓蚀性研究

通过失重法和电化学测试方法研究了在50℃时饱和H2S／CO2介质中季铵盐类12-s-12（s=2,3,4,5和6）型Gemini表面活性剂对Crl3钢的吸附缓蚀性能及其机理。结果表明：50℃时Gemini表面活性剂在饱和H2S／CO2介质中对Crl3钢具有较好的缓蚀效果,其中12—6-12型Gemini表面活性剂的缓蚀性能最佳,缓蚀率能达到90％以上。研究得出间隔基变化对表面活性剂缓蚀性能的影响规律．用电化学极化曲线法和交流阻抗谱图讨论了这种规律的作用机理。12-s-12型Gemini表面活性剂为阴极型缓蚀剂。     

Rosemary oil as a corrosion inhibitor for carbon steel in 0.5 M sulfuric acid solution

The possibility of using rosemary oil as a corrosion inhibitor of carbon steel in 0.5 M sulfuric acid solution was investigated by determination of weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy. It was shown that the inhibition effectiveness increases with an increase in the concentration of oil and a decrease in the temperature. The inhibiting effect of the investigated oil is due to its adsorption on the surface of the steel and complexation. Adsorption is described by a Langmuir isotherm. The effect of the temperature on the corrosion rate was studied in the presence and absence of the oil and the thermodynamic parameters of the corrosion process were calculated.     

Isatin compounds as corrosion inhibitors for N80 steel in 15% HCl

The inhibition effect of two synthesized isatin compounds namely 1-morpholinomethyl-3-(1-N-dithiooxamide)iminoisatin [MMTOI] and 1-diphenylaminomethyl-3-(1-N-dithiooxamide)iminoisatin [PAMTOI] on the corrosion inhibition of N80 steel in 15% HCl solution was studied by polarization, EIS and weight loss measurements. It was found that both the inhibitors were effective and their inhibition efficiency was significantly increased with increasing concentration. Polarization curves revealed that the used inhibitors represent mixed-type inhibitors. Adsorption of these inhibitors led to a reduction in the double layer capacitance and an increase in the charge transfer resistance, and was found also to obey Langmuir isotherm.     

Inhibition of mild steel corrosion and calcium sulfate formation in highly saline synthetic water by a newly synthesized anionic carboxylated surfactant

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.     

Effective inhibition of mild steel corrosion in hydrochloric acid using EBIMOT,a 1, 3, 4-oxadiazole derivative bearing a 2-ethylbenzimidazole moiety: Electro analytical,computational and kinetic studies

A new organic compound, 5-((2-ethyl-1Hbenzo[d]imidazol-1-yl)methyl)-1,3,4-oxadiazole-2-thiol (EBIMOT) has been investigated for its efficacy in the corrosion inhibition of mild steel in 0.5?M HCl at three different temperatures by classical weight loss technique, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) methods. EBIMOT shows high inhibition activity through adsorption and this phenomenon was found to obey Langmuir adsorption isotherm. The kinetic parameters were also derived using the experimental data. The quantum chemical DFT studies were used to correlate the interrelation of inhibition efficiency and molecular structure.