聚乙二醇月桂酸单酯席夫碱基表面活性剂的合成及其缓蚀性能

为了获得缓蚀性能优异的新型表面活性剂,以3种对氨基苯甲酸席夫碱和聚乙二醇月桂酸单酯为原料,合成了3种聚乙二醇月桂酸单酯席夫碱基表面活性剂。利用极化曲线、交流阻抗研究了3种表面活性剂对碳钢在模拟油田水中的的缓蚀性能;利用分子动力学模拟方法对其在Fe(110)表面的吸附行为进行研究,深入探讨其缓蚀机理。结果表明:3种表面活性剂缓蚀性能较好,20℃,100 mg/L时缓蚀率均达80%以上;3种表面活性剂均以其分子结构中的席夫碱基先与Fe表面靠近,分子动力学模拟得出的3种表面活性剂缓蚀性能排序与电化学研究的结果相吻合。     

组氨酸席夫碱的合成及其对碳钢的缓蚀性能

为了研制绿色、低毒的缓蚀剂,采用L-组氨酸和肉桂醛合成了席夫碱,用静态挂片法、电化学方法和扫描电镜(SEM)腐蚀形貌观察系统地评价了该席夫碱在1 mol/L HCl中对A3碳钢的保护行为。结果表明:在该席夫碱浓度为200 mg/L时,缓蚀率达到97.36%;1 mol/L HCl中缓蚀剂在碳钢表面形成较为完整的吸附膜;极化曲线和交流阻抗也都说明了该席夫碱缓蚀剂是以阴极抑制为主的混合型缓蚀剂,其在碳钢表面上的吸附符合Langmuir吸附等温式,是自发吸附过程,吸附机理为兼有物理吸附和化学吸附的混合吸附。     

盐酸溶液中异喹啉在锌表面的吸附及其缓蚀作用

锌换热设备表面积垢常用盐酸进行清洗,因此研究盐酸介质中锌缓蚀剂有重要意义.采用失重法和电化学方法研究了异喹啉在0.8 mol/L盐酸中对锌的吸附及缓蚀作用、吸附热力学和吸附动力学.结果表明,随异喹啉浓度增大,缓蚀率增大,当浓度增大到1g/L后,缓蚀率达到最大值.随温度升高,吸附系数减小,缓蚀率降低.吸附过程是放热过程,△H0=-30.27 kJ/mol.吸附过程熵值减小,且随温度升高,熵变下降.加入异喹啉后腐蚀电流明显减小,过程活化能由3.29 kJ/mol升高至25.56 kJ/mol.异喹啉明显抑制阴极过程,是一种阴极型缓蚀剂.     

水溶性取代吡啶甲酰腙席夫碱的合成及其缓蚀性能研究

合成了5-磺酸钠水杨醛(HQ)以及3种水溶性5-磺酸钠水杨醛取代吡啶甲酰腙席夫碱缓蚀剂(H2B、H3B、H4B)。利用静态失重法、极化曲线、交流阻抗和扫描电子显微镜等方法对其在1mol/L HCl溶液中对Q235钢的缓蚀性能进行了研究。结果表明,浓度为75mg/L时,H4B在1mol/L HCl溶液中对Q235钢的缓蚀效率高达91.10%。扫描电镜照片(SEM)显示,缓蚀剂在碳钢表面形成较为完整的吸附膜。     

盐酸介质中十二烷基苯并三氮唑对碳钢的缓蚀作用

研究了十二烷基苯并三氮唑(DBcs)阳离子表面活性剂的缓蚀性能.通过失重法、极化曲线和SEM考察了该表面活性剂在1.0 mol/L HCl中对碳钢的缓蚀效果,并对缓蚀机理进行了讨论.结果表明:在温度为40℃时,随缓蚀剂DBCS浓度的增加,缓蚀效率增加.当浓度为30 mg/L时该表面活性剂即表现出优异的缓蚀性能,腐蚀速率仅为2.3 g/(m2·h),缓蚀率达98.9%.扫描电镜显示该表面活性剂可在碳钢表面形成致密完整的吸附保护膜,阻碍碳钢的腐蚀.极化曲线表明,该表面活性剂属于阴极抑制为主的混合型缓蚀剂.     

盐酸溶液中3-(4-苯亚甲基-)氨基-1,2,4-三氮唑对5052铝合金的缓蚀性能

为研制一种高效且性能优异的铝合金用酸洗缓蚀剂,以苯甲醛和3-氨基-1,2,4-三氮唑为原料合成了席夫碱3-(4-苯亚甲基-)氨基-1,2,4-三氮唑。通过核磁共振表征了其结构;采用静态失重法、动电位极化法、电化学阻抗法和扫描电镜等研究了其在1 mol/L HCl溶液中对5052铝合金的缓蚀性能。结果表明:所合成的3-(4-苯亚甲基-)氨基-1,2,4-三氮唑在1 mol/L HCl溶液中对5052铝合金具有良好的缓蚀作用,在一定浓度范围内,其缓蚀效率随缓蚀剂浓度的增加而增大,缓蚀剂浓度为5 mmol/L时,缓蚀效率高达95.1%;该缓蚀剂为阴极抑制型缓蚀剂,在5052铝合金表面上的吸附符合Lagmuir吸附,且以化学吸附为主。     

三氯乙酸介质中阴离子表面活性剂对钢的缓蚀性

为了筛选三氯乙酸(Cl3CCOOH)溶液中成本低廉且环境友好的缓蚀剂,用失重法和动电位极化曲线法研究了阴离子表面活性剂十二烷基硫酸钠(SDS)在三氯乙酸溶液中对冷轧钢表面的缓蚀性能,同时采用扫描电子显微镜(SEM)、原子力显微镜(AFM)和接触角测量仪系统表征了钢表面的腐蚀微观形貌及亲水性变化.结果 表明:SDS对冷轧钢在0.10 mol/L Cl3CCOOH中具有良好的缓蚀作用,缓蚀率随SDS浓度增加而增大,20℃时SDS用量仅为50 mg/L时缓蚀率可高达90.5％.SDS在钢表面的吸附符合Temkin吸附等温式,标准吸附Gibbs自由能为-27.3 kJ/mol.腐蚀电位在添加SDS后发生负移,对腐蚀阴极反应发生显著抑制作用,但对阳极反应基本无抑制作用.SEM和AFM分析表明冷轧钢表面在含有SDS的Cl3CCOOH中腐蚀程度和表面粗糙度急剧下降,且接触角测试表明缓蚀钢表面的接触角增大.     

吐温-60对钢在H2SO4中的缓蚀性能

用失重法研究了非离子表面活性剂吐温-60对冷轧钢在0.5-7.0 mol/L H2SO4溶液中的缓蚀作用。结果表明：吐温-60对冷轧钢在1.0 mol/L H2SO4溶液中具有良好的缓蚀作用,且在钢表面的吸附符合校正的Langmuir吸附模型。缓蚀率随缓蚀剂浓度的增加而增大,但随温度和硫酸浓度的增加而减小。求出了相应的吸附热力学（吸附自由能ΔG^0, 吸附焓ΔH^0, 吸附熵ΔS^0）和动力学参数（腐蚀速率常数k, 腐蚀动力学常数B）,并根据这些参数讨论了缓蚀作用机理。     

新型三唑衍生物缓蚀剂对Q235-A钢H2SO4酸洗的缓蚀作用

钢材酸洗添加缓蚀剂是一种有效、经济的防腐蚀方法,研究缓蚀剂的作用机理,发展和完善缓蚀剂的理论已成为研究的热点.采用失重法、电化学方法研究了新型三唑衍生物对Q235-A钢在1 mol/L H2SO4中的缓蚀性能、机理和表面的吸附行为.结果表明:新型三唑衍生物缓蚀剂是一种混合型缓蚀剂,在1mol/L H2SO4溶液中,其浓度为1 000 mg/L时缓蚀率最高达94.6%;在Q235-A钢表面的吸附行为符合Bockris-swinkels吸附等温式.     

一种含硫杂环双席夫碱化合物在硫酸介质中对Q235碳钢的缓蚀作用

目前对于双席夫碱化合物用作碳钢缓蚀剂的研究报道较少。合成了一种含硫杂环双席夫碱化合物:双噻吩-2-甲醛缩邻苯二胺(DTCPA),采用静态失重法、动电位极化曲线和交流阻抗谱测试考察了其在0.5 mol/L H_2SO_4溶液中对Q235碳钢的缓蚀作用。结果表明,DTCPA对碳钢具有良好的缓蚀效果,随着DTCPA浓度的增加腐蚀速率下降,缓蚀效率不断提高;然而,随着温度升高,腐蚀速率加快,缓蚀效率下降。DTCPA在硫酸介质中对碳钢的缓蚀作用属于一种抑制阴阳两极反应的混合型缓蚀剂,在碳钢表面形成了一层致密的保护膜,有效阻挡了硫酸对碳钢的腐蚀,其在碳钢表面的吸附遵循Langmuir吸附等温式。     

苯并咪唑在KOH溶液中对锌材的缓蚀性能

锌电极材料的优良缓蚀剂汞有剧毒,以苯并咪唑缓蚀剂取代汞有益于环保。采用失重法、电化学方法等研究了0．1mol／LKOH溶液中苯并咪唑对锌的缓蚀性能。结果表明：苯并咪唑能有效抑制锌的阳极氧化,从而抑制锌在碱液中的自腐蚀,属于阳极型缓蚀剂;当苯并咪唑浓度为10．0mmol／L时缓蚀效果最佳,缓蚀率可达96．68％;苯并咪唑...     

新型不对称双季铵盐表面活性剂的制备及缓蚀性能

本文以十二烷基二甲基叔胺、十六烷基二甲基叔胺、氯乙酰氯和1,3-丙二胺为原料,通过三步法制得一种新型高效、环境友好的不对称双季铵盐表面活性剂,研究了其在1 mol/L盐酸溶液中对2024 Al-Cu-Mg合金表面的缓蚀性能和机理.通过红外光谱和核磁共振氢谱对其结构进行表征;通过表面张力获得其临界胶束浓度(CMC);利用...     

葡萄糖与甘氨酸反应产物对碳钢的缓蚀效果

为了解葡萄糖与甘氨酸反应产物对碳钢的缓蚀效果,采用失重法、电化学法并结合扫描电镜观察,研究了葡萄糖与甘氨酸反应产物(PGG)对碳钢在1 mol/L HCl溶液中的腐蚀抑制作用。结果发现:PGG对碳钢表现出很好的缓蚀效果,缓蚀效率随添加浓度的增加而增加,在最大浓度250 mg/L时,表现出最好的缓蚀效果,缓蚀效率为94.7%,且缓蚀效率随温度升高而降低。PGG同时抑制了碳钢腐蚀的阴极还原反应和阳极氧化反应过程,为混合型缓蚀剂,是通过多组分的物理和化学联合吸附,在碳钢表面上形成保护性覆盖层,将碳钢与酸溶液隔离,从而起到缓蚀作用,其吸附行为遵循Langmuir吸附等温模型。葡萄糖与甘氨酸反应产物(PGG)是碳钢在1 mol/L HCl溶液中的优良缓蚀剂。     

A review of surfactants as corrosion inhibitors and associated modeling

Surfactants have been commonly used as corrosion inhibitors for the protection of metallic materials against corrosion. The amphiphilic nature of surfactant molecules creates an affinity for adsorption at interfaces such as metal/metal oxide–water interface. The adsorption of surfactant on metals and metal oxides creates a barrier that can inhibit corrosion. The properties of surfactant and the interaction of surfactant with metal or metal oxide and the surrounding solution environments determine the level of adsorption and corrosion inhibition. Understanding and modeling the behavior of surfactants in corrosive environments is critical to optimal utilization of surfactants as corrosion inhibitors. This review of surfactants as corrosion inhibitors is designed to provide systemic evaluation of various physical and chemical properties of surfactants, surfactant behaviors in corrosive environments, and their influence in corrosion inhibition, which can be used to improve the effectiveness with which surfactants are used as corrosion inhibitors in a variety of environments. Progress in the development of various predictive models, including semi-empirical models, mechanistic models, and multiphysics models, are reviewed for the evaluation and prediction of surfactant properties and surfactant corrosion inhibition efficiency. Applications of these models to experimental design and analysis, surfactant design and selection, and lifetime prediction are also discussed.     

桂花果提取液在1 mol/L盐酸介质中对A3钢的缓蚀性能

为了开发A3钢盐酸清洗中的天然绿色缓蚀剂,通过索式提取法从桂花果中提取植物缓蚀剂,采用失重法、极化曲线和电化学阻抗谱(EIS)研究了不同浓度桂花果提取液在1 mol/L盐酸介质中对A3钢的缓蚀性能,并探讨了缓蚀机理。结果表明:以95%的乙醇为溶剂索式提取的桂花果提取液在1 mol/L盐酸介质中对A3钢具有良好的缓蚀性能,缓蚀效率随其浓度的增加而增大,当其浓度达到25 g/L时,缓蚀效率可达93%以上;桂花果提取液为混合型缓蚀剂,缓蚀机理为"几何覆盖效应",其有效缓蚀成分在A3钢表面的吸附符合Langmuir等温式,吸附平衡常数为1.89 L/g。     

A green and effective corrosion inhibitor of functionalized carbon dots

In this work, a green and effective corrosion inhibitor of functionalized carbon dots (FCDs) was synthesized by the conjugation of imidazole and citric acid carbon dots (CA-CDs). The corrosion inhibition behavior of FCDs for Q235 steel in 1 M HCl solution was systematically investigated by electrochemical analysis, corrosion morphology and adsorption isotherm. The electrochemical results implied that the as-prepared FCDs inhibitor could effectively suppress the corrosion of Q235 steel in 1 M HCl solution. At the same time, the inhibition efficiency of steel in 1 M HCl solution was more than 90% when the inhibitor concentration exceeded 100 mg/L. This excellent property was attributed to the coverage of adsorption film on the steel surface, which conformed to the Langmuir adsorption model. In addition, the analysis of adsorption isotherm displayed that the adsorption mechanism was the physicochemical interaction at the steel/solution interface.     

Synthesis of a new family of Schiff base nonionic surfactants and evaluation of their corrosion inhibition effect on X-65 type tubing steel in deep oil wells formation water

Some new Schiff base nonionic surfactants were synthesized and characterized using FTIR and ¹H NMR spectroscopy. The corrosion inhibition effect of the synthesized surfactants on X-65 type tubing steel in deep oil wells formation water has been studied by polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. Polarization data indicate that the selected surfactants act as mixed type (cathodic/anodic) inhibitors. EIS results show that the change in impedance parameters with the concentration of the surfactants studied is indicative of the adsorption of surfactant molecules on carbon steel surface. The adsorption of the inhibitors was well described by the Langmuir adsorption isotherm. Effect of temperature on the efficiency of the corrosion inhibition process was studied and the values of activation energy, enthalpy of activation and entropy of activation were calculated and discussed. The corrosion inhibition efficiency of the surfactants is correlated with surface tension measurements data. The protective film formed on the carbon steel surface was studied by scanning electron microscopy (SEM) and energy dispersive analysis of X-rays (EDX) techniques.     

Synthesis of bridged β-cyclodextrin–polyethylene glycol and evaluation of its inhibition performance in oilfield wastewater

The bridged β-cyclodextrin–polyethylene glycol (β-CD–PEG) is synthesized through reaction of β-CD with PEG, which has been characterized by Fourier transform infrared spectroscope. The inhibition efficiency of bridged β-CD–PEG on corrosion of Q235 carbon steel in 0.5 M HCl solution has been investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization and weight loss measurements. The results show that β-CD–PEG acted as a mixed-type inhibitor and performed excellent inhibiting effect for the corrosion of the Q235 carbon steel. The steel surface morphologies are analyzed using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) and then an adsorption mechanism model is proposed. The high inhibitory efficiency of β-CD–PEG is related with the adsorption of polymer molecules at the steel surface and a protective film formation. Finally, these results present a novel corrosion inhibitor works in oil-gas field.     

Adsorption and corrosion inhibition effect of 2-((5-mercapto-1,3,4-thiadiazol-2-ylimino)methyl)phenol Schiff base on mild steel

In this study, the inhibition effect of 2-((5-mercapto-1,3,4-thiadiazol-2-ylimino)methyl)phenol Schiff base (MTMP) on mild steel corrosion in 0.5 M HCl solution was studied. For this aim, electrochemical techniques such as potentiodynamic polarization curves, weight loss (WL), electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) were used. It was shown that, the MTMP Schiff base has remarkable inhibition efficiency on the corrosion of mild steel in 0.5 M HCl solution. Polarization measurements indicated that, the studied inhibitor acts as mixed type corrosion inhibitor with predominantly control of cathodic reaction. The inhibition efficiency depends on the concentration of inhibitor and reaches 97% at 1.0 mM MTMP. The remarkable inhibition efficiency of MTMP was discussed in terms of blocking of electrode surface by adsorption of inhibitor molecules through active centers. The adsorption of MTMP molecules on the mild steel surface obeys Langmuir adsorption isotherm.