HCl介质中巯基三唑缓蚀吸附膜对碳钢的保护时间的研究

 合成两种新型巯基三唑缓蚀剂，利用交流阻抗测试(EIS)结果，建立了10 M HCl介质中缓蚀剂吸附膜对碳钢缓蚀保护作用时间的预测方程，分析了预膜时间和金属表面状态等因素对缓蚀吸附膜保护时间的影响.     

鱼内脏水解液(FVH)与竹叶提取液(BLE)在HCl介质中的协同缓蚀作用

研究了鱼内脏水解液FVH和竹叶提取液BLE两种酸洗缓蚀剂分别对碳钢在HCl介质中的缓蚀作用及复配后的缓蚀效果。结果表明这两种缓蚀剂具有良好的协同缓蚀作用。     

含席夫碱结构碳点缓蚀剂的简易可扩展制备及性能研究

目的 克服目前制备碳点(Carbon dots, CDs)缓蚀剂存在的耗时、耗能等缺点，在室温下一步制备含席夫碱结构的CDs缓蚀剂，并研究其对Q235碳钢的缓蚀性能。方法 设计了一种简易、可扩展的制备方法，以邻苯二胺和对苯醌为前驱体，无需高温加热便可在室温下反应2 h，从而获得含席夫碱结构的CDs。利用TEM等方法对其结构进行表征，并采用UV和PL光谱评估其在HCl溶液中的长期分散稳定性。通过失重法、电化学测试方法研究了不同浓度CDs对Q235碳钢在1 mol/L HCl溶中的缓蚀性能。通过SEM和三维轮廓测量仪分析腐蚀后碳钢表面形貌及化学组成，提出CDs的缓蚀机理。结果 CDs含C=N键，具有多种含氧、含氮基团，有利于其在钢表面的吸附。CDs在HCl溶液中具有长期分散稳定性。当添加浓度为200 mg/L时，其对碳钢在1 mol/L HCl溶液中的缓蚀效率可达到95.05%。CDs为混合型缓蚀剂，能够同时抑制阴极和阳极反应。CDs在碳钢表面的吸附方式遵循Langmuir等温吸附模型，其缓蚀机理为通过物理和化学吸附方式在碳钢表面形成一层保护膜，从而抑制碳钢的腐蚀。结论 成功为CDs缓蚀剂的合成提供了一种简易、可扩展、高效、省时的方法，而且证明了具有席夫碱结构的CDs对碳钢在1 mol/L HCl溶液中的腐蚀具有显著的抑制能力。     

三聚氰胺对碳钢在 HCl 介质中的缓蚀作用

目的了解在HCl介质中,三聚氰胺对碳钢的缓蚀作用和缓蚀机理。方法在1 mol/L HCl溶液中添加不同浓度的三聚氰胺,测试碳钢在溶液中的动电位极化曲线和电化学阻抗谱,获得电化学参数和缓蚀效率。再结合量子化学计算结果,分析其缓蚀机理。结果针对碳钢在1 mol/L HCl溶液中的腐蚀,三聚氰胺是一种混合抑制型缓蚀剂,随其浓度的增加,缓蚀效率增大。三聚氰胺通过分子中Mulliken电荷相对较负的氮原子吸附在碳钢表面起到缓蚀作用,吸附过程为自发过程,以物理吸附为主,且符合Langmuir吸附等温方程。结论在HCl介质中,三聚氰胺对碳钢具有一定的缓蚀作用。     

一种咪唑烷硫酮衍生物的缓蚀性能

以硫脲、二乙烯三胺和有机羧酸为原料制备一种咪唑烷硫酮衍生物缓蚀剂(CI-R缓蚀剂),采用失重法、极化曲线法、扫描电镜(SEM)观察等方法,研究了缓蚀剂CI-R在85℃、500μg/g HCl+1%NH4Cl(质量分数,下同)溶液中对碳钢的缓蚀作用及其吸附模型。结果表明:缓蚀剂CI-R是一种混合型缓蚀剂,对试验溶液中的碳钢具有良好的缓蚀作用,加入量为20μg/g时,缓蚀率可达90.9%;其在碳钢表面的吸附遵循Langmuir吸附等温式,通过在碳钢表面形成一层致密的保护膜,阻碍腐蚀介质与金属基体的接触,抑制了金属的腐蚀。     

黄连提取物在1 mol/L HCl中对Q235的缓蚀作用

从黄连中提取出的固体物质,可做为一种优良的天然绿色缓蚀剂.本文用失重和电化学测试等方法研究了黄连提取物在1 mol/L HCl中对Q235的缓蚀作用.结果表明,黄连提取物在1 mol/L HCl中对Q235有高达98％的缓蚀作用,其在碳钢表面的吸附符合Langmuir等温式,能同时抑制碳钢腐蚀的阴、阳极过程,碳钢的阻抗值随黄连提取物浓度增加而变大,扫描电镜分析结果也表明该提取物对碳钢表面有很好的保护作用.      

新型巯基三唑化合物对HCl介质中碳钢的缓蚀作用研究

合成了两种新型巯基三唑化合物，分别采用腐蚀失重法、动电位扫描极化曲线和交流阻抗法研究了其在1．0mol／L HCl介质中对Q235钢的缓蚀作用，分析了缓蚀作用机理．结果表明：对碳钢在1．0mol／L HCl溶液中，合成的巯基三唑化合物是性能优异的缓蚀剂．     

三苯环咪唑啉季铵盐的合成与缓蚀性能

利用两步法合成了三苯环咪唑啉季铵盐缓蚀剂(简称Q ATI)，并对其结构进行了表征，通过腐蚀失重法、电化学测定等方法对其在HCl、H2SO4 酸洗液中对碳钢的缓蚀效果进行测定.结果表明，三苯环咪唑啉季铵盐缓蚀性能优异.同时探 讨了其缓蚀机理.     

新型恶二唑类缓蚀剂的合成及其缓蚀性能

合成了一种恶二唑类缓蚀剂 2,5-(2-十一烷基)-1,3,4恶二唑 (简称 HOX),对其进行了表征,并采用静态失重法、动电位极化和电化学阻抗谱 (EIS) 研究其在HCl介质中对 Q235 钢的缓蚀作用.研究表明,所合成的恶二唑类化合物是一种性能优异的混合控制型酸性碳钢缓蚀剂,其在碳钢表面的吸附符合Langmuir吸附模型.     

双咪唑啉季铵盐的合成与缓蚀性能研究

利用两步法合成了双咪唑啉季铵盐化合物，通过失重法研究了该化合物在1g／L HCl 0．16g／L H2S 1g／L NaCl溶液和10％的盐酸溶液中对碳钢的缓蚀性能，讨论了用量、温度、时间对缓蚀性能的影响，并通过极化曲线和扫描电镜研究了该化合物的缓蚀机理。结果表明，该化合物在HCl-H2S-NaCl-H2O和10％的盐酸腐蚀环境中对碳钢具有良好的缓蚀作用，是一种以阳极控制为主的混合型缓蚀剂。     

含二长链烷基溴化铵的合成及其缓蚀性能和吸附模型的研究

以二甲基十六烷基胺等为原料,合成了十六烷基辛基二甲基溴化铵和十六烷基癸基二甲基溴化铵,用线性极化法研究了它们对５％ＨＣｌ中碳钢的缓蚀作用,并确定了它们的吸附模型。结果表明：它们对酸液中碳钢的腐蚀具有明显的抑制作用,在碳钢表面的吸附遵循Ｌａｎｇｍｕｉｒ等温式。     

Carbonyl compounds as corrosion inhibitors for mild steel in HCl solutions

The paper gives an account of the performance of a number of carbonyl compounds as corrosion inhibitors of mild steel in 1–6 N solutions of hydrochloric acid. Furfuraldehyde seems to be the best inhibitor of all the carbonyl compounds investigated. Activation energies in the presence and absence of inhibitors have been evaluated. In cathodic protection studies furfuraldehyde reduces the protective current density considerably. The difference effect is positive in the absence and presence of inhibitors. Galvanostatic polarization data indicate that all these compounds are predominantly cathodic inhibitors. These substances are more effective in preventing the corrosion of aluminium alloys in hydrochloric acid solutions than the corrosion of mild steel.     

Untersuchungen zum Einfluß von Inhibitoren auf die Wasserstoffversprödung von unlegiertem Stahl in Salzsäure

Investigations on the influence of inhibitors on hydrogen embrittlement of mild steel in hydrochloric acid The influence of four commercially available inhibitors as well as their main effective components on the corrosion behaviour of mild steel in 16 and 32% hydrochloric acid was investigated by potentiokinetic polarisation measurements, electrochemically controlled measurements of hydrogen permeation and by estimating the rate of mass loss. The inhibitors showed different, yet positive effects on the inhibition of the permeation of cathodically produced hydrogen. The best results were found with benzylchinolinium chloride as inhibitor. Particularly in acids containing hydrogen sulfide propargylalcohol turned out to be a poor inhibitor of hydrogen permeation. Under these conditions the addition of propargylalcohol to quart. ammonium salts even decreased their good effectiveness as single components. The fact that the effectiveness for the inhibition of hydrogen permeation often diminished in the course of short periods was not due to a simultanous increase of the corrosion rate.     

Influence of 2,3-Dihydroxyflavanone on Corrosion Inhibition of Mild Steel in Acidic Medium

The inhibition effect of 2,3-dihydroxyflavone on the corrosion of mild steel in 100-600 ppm aqueous hydrochloric acid solution has been investigated by weight loss and electrochemical impedance spectroscopy. The corrosion inhibition efficiency increases with increasing concentration and time. The effect of temperature on the corrosion behavior of mild steel in 1 M HCl with addition of inhibitor was studied at the temperature range of 300-330 K. UV-Vis, FTIR, and surface analysis (SEM) was also carried out to establish the corrosion inhibitive property of this inhibitor in HCl solution. The adsorption of this inhibitor on the mild steel surface obeys the Langmuir adsorption isotherm. Electrochemical studies reveal that the inhibitor is a cathodic type.     

A comparative study of corrosion inhibition efficiency of stem and leaves extract of <Emphasis Type="Italic">Ocimum sanctum</Emphasis> (Holy Basil) for mild steel in HCl solution

Corrosion inhibition efficiency of Ocimum sanctum extract for mild steel in hydrochloric acid solution was studied by weight loss and thermometric methods. Inhibition efficiency increases with the increasing concentration of extract and decreases with increase in acid strength. Results of inhibition efficiency obtained by two methods have been found in good agreements with each other. Maximum inhibition efficiency was found 98.67% in 0.5 N HCl acid with 1.2% stem extract, whereas it was 96.02% in leaves extract with same concentration i.e. 1.2%.     

Corrosion Protection of Mild Steel with Polyaniline–Thiokol Rubber Composite Coatings

The anti-corrosion performance of polyaniline-thiokol rubber (PANI/TR) composite coating applied to mild steel samples in artificial brine and hydrochloric acid environments is for the first time evaluated in this paper. The PANI/TR composite -coatings on mild steel were electropolymerized in a nonaqueous solution. EDS, XPS and SEM were concurrently used to characterize the structure, as well as composition of the coating and show that the structure is favorable to the corrosion protection. Both potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) demonstrated that the PANI/TR coating outperforms PANI coating both in the adhesion to the substrate and its corrosion protection, making the free corrosion potential by about 100mV more positive. As a result, the mild steel corrosion was greatly impeded by applying PANI/TR composite conductive polymer coating.     

米糠提取液作为盐酸酸洗缓蚀剂的研究

用盐酸酸化浸取法从米糠中提取植酸,并将其作为盐酸酸洗缓蚀剂的主要成分;采用失重挂片、线性极化和电化学阻抗等方法评价该缓蚀剂的缓蚀效率,并初步探讨其缓蚀机理。结果表明：该缓蚀剂对碳钢在1 mol/L HCl 溶液中有良好的缓蚀效果,且缓蚀效率受温度影响较小,属于阴极型缓蚀剂。     

Corrosion inhibition of mild steel by plant extract in dilute HCl medium

The inhibition effect of Zenthoxylum alatum plant extract on the corrosion of mild steel in 5% and 15% aqueous hydrochloric acid solution has been investigated by weight loss and electrochemical impedance spectroscopy (EIS). The corrosion inhibition efficiency increases on increasing plant extract concentration till 2400 ppm. The effect of temperature on the corrosion behaviour of mild steel in 5% and 15% HCl with addition of plant extract was studied in the temperature range 50-80 °C. Surface analysis (SEM, XPS and FT-IR) was also carried out to establish the corrosion inhibitive property of this plant extract in HCl solution. Plant extract is able to reduce the corrosion of steel more effectively in 5% HCl than in 15% HCl. The adsorption of this plant extract on the mild steel surface obeys the Langmuir adsorption isotherm.     

Assessing the possibility of stress corrosion cracking during acid cleaning

During chemical cleaning large volumes of inhibited acids are pumped through boilers and there is a possibility of stress corrosion cracking occurring under certain conditions. This paper examines four material/environmental combinations encountered in practice: mild steel in inhibited hydrochloric acid, mild steel, a 9%Cr-1%Mo steel and a sensitized austenitic stainless steel in inhibited citric acid. The electrochemistry of each is examined, various predictability tests performed, and these compared to the results of slow strain-rate stress corrosion tests. No stress corrosion occurred with the material-environmental-stress conditions which should be encountered in practice; however, cracking could be induced to occur by out of specification conditions. The results of the predictability tests did not correlate with the observed cracking susceptibilities. However this lack of agreement could be explained with a detailed knowledge of the electrochemistry involved in each system.