Experimental and Theoretical Investigation by DFT on the Some Azole Antifungal Drugs as Green Corrosion Inhibitors for Aluminum in 1.0M HCl

Protection of Metals and Physical Chemistry of Surfaces - The inhibiting power of three compounds of azole antifungal drugs to ward the dissolution of aluminum in 1.0 MHCl solutions was elaborated...     

Electrochemical and Molecular Dynamic Investigation of Some New Pyrimidine Derivatives as Corrosion Inhibitors for Aluminium in Acid Medium

Protection of Metals and Physical Chemistry of Surfaces - A new class of corrosion inhibitors, namely, pyridine-2,6-diamine (PD) , pyrimidin-2-amine (PA), 6-amino-3,4-dihydropyrimidine-2(1H)-thione...     

电化学法研究芭蕉叶提取物在盐酸中对碳钢的缓蚀作用

目的研究芭蕉叶提取物(MBLE)在酸性环境中对碳钢腐蚀的抑制行为。方法通过热水浸提法获取MBLE,采用电化学方法研究在不同实验温度和不同浓度下MBLE在1 mol/L盐酸溶液中对碳钢的缓蚀行为,并用扫描电镜(SEM)研究金属表面腐蚀形貌。结果极化曲线研究表明,MBLE对碳钢在1mol/L盐酸中的腐蚀有明显抑制作用,属阴极抑制为主的混合型缓蚀剂;其缓蚀性能随质量浓度增大而增强,25℃时160 mg/L的MBLE缓蚀效率达到94.7%。电化学阻抗图谱研究表明,随着MBLE质量浓度的增大,碳钢表面腐蚀反应的电荷转移电阻逐渐增大,腐蚀反应抑制程度增强。变温试验研究表明,MBLE在实验温度范围内具有较好的稳定性。当MBLE质量浓度为160 mg/L时,温度从25℃增加到40℃,两种电化学方法所得缓蚀效率的变化幅度均在3%以内。MBLE缓蚀剂分子在碳钢表面的吸附服从Dhar-Flory-Huggins等温吸附式,并且属于物理和化学混合吸附。SEM研究表明,盐酸介质中MBLE可有效地抑制碳钢的腐蚀。结论对碳钢在盐酸介质中的腐蚀,MBLE是有效的绿色缓蚀剂。     

Synthesis and Estimation of Some Surface-Active Compounds Derived from Fused Pyridine as Corrosion Inhibitors for Aluminum in Hydrochloric Acid Solutions

Protection of Metals and Physical Chemistry of Surfaces - Three nonionic surfactants molecules (NS) derived from a fused pyridine characterized by IR and 1HNMR spectra were synthesized and examined...     

The Effect of TiB2 on Electrochemical Performance of Udimet 700 Alloy in 1 M Hydrochloric Acid Solution and Its Corrosion Inhibition Using Some Organic Derivatives

Protection of Metals and Physical Chemistry of Surfaces - The effect of adding 5 and 10% of TiB2 on the corrosion of Udimet 700 (U700) in 1 M HCl including altered concentrations of organic...     

Thermodynamic and Electrochemical Studies of Aniline and Phenylhydrazine and Their Derivatives Substituted POCl3-Based Compounds as Corrosion Inhibitor for Mild Steel in Hydrochloric Acid Solution

Protection of Metals and Physical Chemistry of Surfaces - The achievement of high corrosion inhibition performances by manipulating the molecular structure of organic substances has gained much...     

纯铝在盐酸中腐蚀动力学研究

用失重法研究了纯铝在不同浓度盐酸介质中不同温度下的腐蚀规律,从而获得了酸度参数、速率常数、反应活化能和指前因子等重要动力学参数。     

Effect of Thiourea and some of its Derivatives on the Corrosion Behaviour of Cobalt in Concentrated Hydrochloric Acid

Abstract

The corrosion rate of cobalt in 8·4 M hydrochloric acid with and without the presence of thiourea, phenyl thiourea, o-tolyl thiourea or sym di-isopropyl thiourea has been studied by gravimetric and electrochemical methods over the temperature range, 20–80°c.

In all cases these compounds brought about enhancement of corrosion so that, at the higher temperatures, corrosion rates some twenty times those experienced in acid alone were attained. These matched the degree of corrosion stimulation of cobalt developed in the presence of hydrogen sulphide and it is suggested that the thiourea compounds act as depolarisers for the hydrogen evolution reaction, with H₂S being a product of the chemical depolarisation stage. The H₂S is considered to be adsorbed in the molecular state, forming activated sites where anodic dissolution is thereby enhanced.     

New Corrosion Inhibitors for Low-Carbon Steel in Hydrochloric Acid Solutions

Protection of Metals and Physical Chemistry of Surfaces - Abstract—The effects that indolizine derivatives, a tellurium organic compound, rhodanine, sodium diethyldithiocarbamate, and some of...     

Interaction of Benzimidazoles and Benzotriazole: Its Corrosion Protection Properties on Mild Steel in Hydrochloric Acid

Synergistic hydrogen-bonded interaction of alkyl benzimidazoles and 1,2,3-benzotrizole and its corrosion protection properties on mild steel in hydrochloric acid at different temperatures have been studied using polarization, EIS, adsorption, surface studies, and computational methods. The extent of synergistic interaction increases with temperature. Quantum chemical approach is used to calculate some electronic properties of the molecules and to ascertain the synergistic interaction, inhibitive effect, and molecular structures. The corrosion inhibition efficiencies and the global chemical reactivity relate to some parameters, such as total energy, E _HOMO, E _LUMO, and gap energy (ΔE). 1,2,3-Benzotrizole interacts with benzimidazoles derivatives up to a bond length of approximately 1.99 Å. This interaction represents the formation of a hydrogen bond between the 1,2,3-benzotrizole and benzimidazoles. This synergistic interaction of 1,2,3-benzotrizole and benzimidazole derivatives offers extended inhibition efficiency toward mild steel in hydrochloric acid.     

HastelloyB3合金在盐酸中的腐蚀行为

通过浸泡试验、电化学试验研究了HastelloyB3合金在不同条件盐酸中的腐蚀行为。结果表明:合金在不同HCl含量与温度的纯盐酸中均具有良好的耐蚀性,随着温度与HCl含量的提高,合金腐蚀速率虽有所增长,但仍然处于钝化态;盐酸中添加氧化性离子Fe~(3+)后,腐蚀速率急剧增大并伴随着点蚀,随着Fe~(3+)含量的提高,腐蚀速率快速增大;在纯盐酸中,HastelloyB3表面生成Mo~(4+)钝化膜,对基体起到保护作用,但添加氧化性Fe~(3+)后,钝化膜中的Mo~(4+)极易被氧化成Mo~(6+),发生溶解,使合金由钝态向过钝化态转变,导致耐蚀性急剧下降;HastelloyB3合金适用于不同HCl含量与温度的纯盐酸中,但不适用于含氧化性离子或溶解氧高的盐酸中。     

Benzodiazepine Derivatives as Corrosion Inhibitors of Carbon Steel in HCl Media: Electrochemical and Theoretical Studies

Protection of Metals and Physical Chemistry of Surfaces - New benzodiazepine derivatives, namely 8-Chloro-1,2,3,4,10,11-hyxahydrospiro[cyclohexane-1,11-dibenzo[1,4]diazipine] and...     

Experimental and Quantum Studies on Adsorption and Corrosion Inhibition Effect on Mild Steel in Hydrochloric Acid by Thiophene Derivatives

The inhibition effect of synthesized diethyl 3,4-bis(4-methoxybenzylideneamino) thieno[2,3-b]thiophene-2,5-dicarboxylate(Inh I) and diethyl 3,4-bis(benzylideneamino) thieno[2,3-b]thiophene-2,5-dicarboxylate(Inh Ⅱ),on corrosion of mild steel in 15%HC1 solution was investigated using weight loss measurements,electrochemical polarization,and electrochemical impedance spectroscopy techniques.The experimental results show that the inhibition efficiency of studied inhibitors increased with the increase of inhibitors concentration but decreased with the increase of temperature.Corrosion inhibition efficiencies of 94.5%and 92.1%were obtained with 250 ppm of Inh I and Inh Ⅱ at 303 K,respectively.The potentiodynamic polarization measurements indicate that the studied inhibitors act as mixed inhibitor.The thermodynamic parameters of the corrosion and adsorption processes were calculated and evaluated.The adsorption of these inhibitors was found to obey Langmuir adsorption isotherm.Scanning electron microscopy was used to characterize the surface morphology of the mild steel specimens in presence and absence of inhibitors.The mechanism of the inhibition process was discussed in the light of the chemical structure and quantum-chemical calculations of the investigated inhibitors.     

核桃叶提取物在盐酸介质中对钢的缓蚀性能

核桃（Juglans）叶提取物（JLE）可以作为“绿色”环保的植物缓蚀剂。本工作采用失重法和动电位极化曲线研究了JLE在1mol／LHCI溶液中对冷轧钢的缓蚀作用。结果表明,JLE对冷轧钢具有较好的缓蚀作用,且存钢表面的吸附符合校正的Langmuir吸附等温式,极化曲线表明,JLE为混合抑制型缓蚀剂。     

海洋工程用铝合金的腐蚀与防护研究进展

海洋工程用铝合金部件在服役环境下引发的点蚀、晶间腐蚀等已成为困扰机器装备使用寿命和稳定性的关键问题。目前,阴极保护、缓蚀剂、阳极氧化和保护涂层是针对海洋环境中铝合金腐蚀的常用防护措施。阐述了海洋工程装备常用的铝合金类型和使用场所,发现5系和6系铝合金是船舶制造和海洋平台搭建的首选材料,其中,具备优异力学性能、耐腐蚀性能的5系铝合金一般用来制作甲板、储存装置等大型主要承力构件。重点综述了铝合金在海洋大气区、浪花飞溅区、海水全浸区的腐蚀行为和腐蚀机制,经对比发现,与钢不同,铝合金在海水全浸区的腐蚀最严重,而在环境最恶劣的浪花飞溅区腐蚀损伤相对较轻;点蚀、晶间腐蚀是2种典型的铝合金腐蚀类型,同时应力腐蚀、微生物腐蚀也制约着铝合金在海洋工程领域的应用。最后分析了当前在海洋环境中对铝合金腐蚀防护采取的几种措施,指出工程实际中采用的防护方式为2种及2种以上措施的联合使用,并提出铝合金未来在失效行为分析、性能优化和涂层材料选择等方面的发展趋势,以期为研发在极端海洋环境下服役的铝合金及其防护材料提供参考。     

Grain Boundary Attack on Aluminum in Hydrochloric Acid and Sodium Hydroxide

The wide grooves formed at the grain boundaries when high purity aluminum is attacked by hydrochloric acid or sodium hydroxide have been attributed by earlier workers to the high energy of the grain boundary material. The effect has been investigated for high-purity Al-Fe alloys with up to 0.055 pet Fe as a function of iron content and heat treatment. It is shown that the explanation given above is untenable, but that the results can be explained on the assumption that iron segregates to the grain boundary in solid solution.     

Inhibition Effect of Rhodanine for Corrosion of Mild Steel in Hydrochloric Acid Solution

The inhibition effect of Rhodanine on the corrosion performance of mild steel (MS) was studied in 0.5 M HCl solution. For this purpose, potentiodynamic polarization, electrochemical impedance spectroscopy, and long-term corrosion tests including hydrogen evolution and change in open-cirquit potential during immersion time were used. To determine activation energy of corrosion process, potentiodynamic polarization curves were also obtained in a temperature range from 298 to 328 K. The results show that Rhodanine effectively inhibits the MS corrosion in hydrochloric acid solution. __________ From Zashchita Metallov, Vol. 41, No. 6, 2005, pp. 628–632. Original English Text Copyright ? 2005 by Solmaz, Kardas, Yazici, Erbil. The text was submitted by authors in English.     

耐浓盐酸介质的铸造高性能合金的研究

本文研究了耐浓盐酸(33～36%HCI),50℃苛刻介质的铸造高性能合金的组织与性能。着重研究了不同的含镍量及改变热处理冷却方式对合金组织与性能的影响。结果表明,含Ni50～60%的铸造高性能合金在温度为50℃的浓盐酸介质中均具有良好的耐蚀性能;水冷试样具有比空冷试样略好的性能,相差幅度不大,因此对于结构复杂壁厚不均匀的铸件可以采用空冷处理;此外,本铸造合金还具有较好的综合机械性能和满意的铸造性能。     

茄叶提取液在盐酸介质中对碳钢的缓蚀性能

通过动电位极化曲线法、电化学阻抗法、失重法和扫描电镜法研究了茄叶提取液在1mol·L-1 HCl中对碳钢的缓蚀性能和机理。结果表明:茄叶提取液的最佳提取条件为盐酸浓度3.0mol·L-1、温度55.0℃、时间62h;在最佳条件下提取的茄叶提取液缓蚀性能优异,当茄叶提取液质量浓度为1 800mg·L-1时,失重缓蚀率达92%以上;茄叶提取液在碳钢表面的吸附符合Langmuir吸附等温模型,茄叶缓蚀剂可显著抑制碳钢的腐蚀。     

Propoxylated Fatty Esters as Safe Inhibitors for Corrosion of Zinc in Hydrochloric Acid

Protection of Metals and Physical Chemistry of Surfaces - The inhibiting action of nonionic surfactants, namely, propoxylated fatty esters (PFE) with different number of propylene oxide toward the...