IAA 在硫酸溶液中对碳钢的缓蚀性能研究

目的研究吲哚-3-乙酸(IAA)在H2SO4(0.1 mol/L)溶液中对碳钢(Q235)的缓蚀性能,降低碳钢生产过程对环境的影响。方法采用动电位极化曲线测试、交流阻抗实验、失重实验和扫描电镜实验分析缓蚀剂的缓蚀性能及作用机理。结果 IAA的缓蚀效率随着缓蚀剂浓度的增加而逐渐增大,当IAA浓度增加到4×10-3mol/L时,缓蚀效率最高达到88.85%。温度升高,缓蚀效率降低,说明IAA不宜于高温下使用。IAA是一种混合型缓蚀剂,对阴极反应和阳极反应均有抑制作用,且在缓蚀剂分子吸附过程中,吸附在碳钢表面的水分子和缓蚀剂分子发生竞争吸附作用,能有效阻止H+的穿越,从而抑制腐蚀H+的放电。IAA在碳钢表面的吸附遵循Langmuir吸附等温模型,该吸附自发进行且是物理吸附和化学吸附共同作用。缓蚀剂通过抑制腐蚀反应的活性点,提高活化能垒,防止碳钢溶解腐蚀。IAA在碳钢表面形成保护膜,减轻了腐蚀。结论 IAA是一种以抑制阳极反应为主的混合型缓蚀剂,在0.1 mol/L H2SO4溶液中能够对Q235碳钢起到优异的保护作用。     

ATA及其与PASP复配在3.5%NaCl溶液中对碳钢的缓蚀作用

为寻找新的缓蚀荆来解决碳钢的腐蚀问题,采用极化曲线和交流阻抗方法,研究了3-氨基-1,2,4-三氮唑(ATA)及其与聚天冬氨酸(PASP)复配在3.5%NaCl溶液中对碳钢的缓蚀作用,并对比观察了碳钢在未加和加入复配缓蚀荆的3.5%NaCl溶液中浸泡后的腐蚀形貌.结果表明:ATA在3.5%NaCl溶液中对碳钢具有缓蚀作用,属阳极型缓蚀剂,其添加量以25 mg/L为最好,此时的缓蚀效果最佳,缓蚀率可达93.51%;ATA和PASP复配在3.5%NaCl溶液中对碳钢具有缓蚀协同作用,且15 mg/L ATA和10 mg/L PASP复配时的缓蚀协同作用最好,缓蚀率高达99.89%.     

Inhibitory action of biodegradable modified vanillin on the corrosion of carbon steel in 1 M HCl

The effects of two biodegradable corrosion inhibitors derived from vanillin and aminophenol (Meta: VPAP and Para: VOAP) on the corrosion of carbon steel in 1 M HCl solution were examined. The efficiency of these inhibitors on carbon steel corrosion increased by increasing the concentration and decreased by increasing the temperature. The inhibitors adsorbed on carbon steel physically and obeyed the Langmuir isotherm. The potentiodynamic measurements showed mixed-type inhibitor. The geometry of the inhibitors showed that VPAP has slightly higher efficiency in corrosion inhibition than VOAP. The inhibitors showed good biodegradability in the environment within 28 days.     

缓蚀剂9912-1在CO_2H_2O介质中缓蚀性能的研究

设计合成了一种成膜型的氮杂环的季胺盐缓蚀剂 9912 1。测试了其在 90℃下二氧化碳饱和的 3%NaCl水溶液中对碳钢的缓蚀性能 ,探讨了缓蚀剂用量与缓蚀率的关系 ,及其与复配物的协同效应 ,从中得出了较佳的缓蚀配方。实验结果表明 ,此种缓蚀剂对碳钢有良好的缓蚀效果 ,可作为中高温条件下CO2 环境中的缓蚀剂。     

可溶性聚酰亚胺LB膜对碳钢的缓蚀作用的研究

应用可溶性聚酰亚胺(PI)Langmuir-Blodgett(LB)膜沉积在碳钢电极上,研究其在中性及酸性介质中对碳钢的缓蚀作用.结果表明PILB膜在中性及酸性介质中对碳钢有较好的缓蚀作用,单分子层数目对缓蚀效率有很大的影响.     

硫酸介质中丙氨酸复合缓蚀剂的研究

目的研究丙氨酸和碘化钾共同存在于硫酸溶液中,对碳钢的协同缓蚀作用。方法采用极化曲线、交流阻抗谱、扫描电镜、X射线光电子能谱(XPS)以及El-Awady动力学模型,对丙氨酸、丙氨酸与碘化钾复配缓蚀剂对碳钢在硫酸介质中的缓蚀性能和吸附机理进行探究。结果在10%的硫酸体系中,对碳钢的缓蚀性能随着缓蚀剂浓度增大而增强。单独使用丙氨酸作为缓蚀剂,丙氨酸分子在碳钢表面呈单分子层吸附,缓蚀效率最高仅达到29%,缓蚀效果不明显。经过丙氨酸与碘化钾复配后,缓蚀效果显著提高,当丙氨酸质量浓度为300 mg/L,碘化钾质量浓度为250 mg/L时,缓蚀效率达到92%以上。XPS谱图表明,缓蚀剂主要是通过分子中的N原子与碳钢表面Fe原子形成共价键,吸附在碳钢的表面,与KI复配后,I-吸附在碳钢表面,并部分氧化,形成I_3~-。El-Awady动力学模型研究说明该复配缓蚀剂为混合型缓蚀剂,且在碳钢表面自发形成多分子层吸附膜。结论在10%的硫酸溶液中,丙氨酸分子通过物理吸附或化学吸附作用,吸附在碳钢表面,减缓腐蚀反应发生。碘化钾添加后,发挥连接缓蚀剂分子和碳钢表面的桥梁作用,从而协助丙氨酸吸附到碳钢表面,提高丙氨酸在碳钢表面的覆盖率,在提高缓蚀效率的同时,减少了丙氨酸的使用量,有效地抑制了钢材的腐蚀。     

硫酸介质中榕树叶提取液的缓蚀性能及其与 KI 的缓蚀协同效应

通过电化学方法和失重法,研究了榕树叶提取液(FLE)对碳钢在硫酸溶液中的缓蚀性能,同时研究了它与KI的缓蚀协同效应,探讨了缓蚀机理。研究结果表明:在硫酸溶液中,FLE对碳钢属混合抑制型缓蚀剂,缓蚀效率随其浓度的增加而增大;FLE与KI之间存在良好的协同效应,两者复配后,体系的腐蚀电流密度减小,电荷传递电阻增大,双电层电容减小,缓蚀效率增大,表现出更好的缓蚀作用;FLE与KI复配前后,其在碳钢表面的吸附均为自发过程,且符合Langmuir吸附等温方程。     

Synthesis of bolaamphiphile surfactants and their inhibitive effect on carbon steel corrosion in hydrochloric acid medium

Corrosion inhibition by surfactant molecules is related to the surfactant's ability to aggregate at interfaces and in solution. In this work some new triazole bolaamphiphiles in the series of 1,n-bis(1,2,4-triazolyl)alkane where n=10, 12 have been synthesized. The purity of surfactants synthesized was checked by rutinary methodologies (IR, ¹H NMR, ¹³C NMR, mass spectra and elemental analysis). The aggregation of 1,n-bis(1,2,4-triazolyl)alkane have been determined by surface tension at the air-HCl 1 M interface. The inhibiting action of these compounds towards the corrosion of carbon steel in 1 M HCl solution was investigated using gravimetric, potentiodynamic and electrochemical impedance spectroscopy measurements. Polarization data indicate that these compounds act as very good cathodic inhibitors for carbon steel in 1 M HCl. The values of the transfer resistance, obtained from impedance plots of carbon steel, increase by increasing product concentration. From all measurements carried out, the variation of the inhibition efficiency versus concentration shows the same trend. The electrochemical study shows that DTC12 is the best inhibitor and its efficiency increases with concentration and the highest value obtained is around 94%.     

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。     

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。     

Electrochemical studies on the effect of pyrazolo‐containing compounds on the corrosion of carbon steel in 1 M sulphuric acid

The effect of some synthesized pyrazolo containing compounds on the corrosion of carbon steel in 1 M H₂SO₄ was investigated. The investigation involved electrochemical polarization methods (potentiodynamic, Tafel extrapolation and the determination of the polarization resistance). A significant decrease in the corrosion rate of carbon steel was observed in the presence of the investigated compounds. The results show that these compounds act as mixed type inhibitors, but the cathode is more preferentially polarized. The relative inhibition efficiency of these compounds depends on both the nature and concentrations of the investigated compounds. Compounds are found to adsorb on the carbon steel surface according to the Langmuir adsorption isotherm.     

Corrosion Inhibition of Carbon Steel in 1 M Hydrochloric Acid using Some Pyrazolo[3,4-<Emphasis Type="Italic">d</Emphasis>]Pyrimidnone Derivatives

The inhibiting effect of three compounds of pyrazolo[3,4-d] pyrimidnone derivatives toward the corrosion of carbon steel in 1.0M HCl solution was investigated using galvanostatic and potentiodynamic anodic polarization techniques. The rise of the concentration of the inhibitors and decreasing the temperature led to the greater of inhibition efficiency. The inhibiting action of these compounds was explicated on the footing of its adsorption on the carbon steel surface. The adsorption operation of these compounds was obeyed Langmuir isotherm. There is only one anodic peak during the anodic cyclic voltammogram This peak was elucidated due to the active dissolution of Fe as Fe²⁺. The percentage inhibition efficiency was computed from the values of peak current density.There is a good convention between the values of the percentage inhibition efficiency gained from the diverse techniques.These compounds inhibit the pitting corrosion of carbon steel by shifiting the pitting corrosion potential to more noble direction. The effect of elevation of temperature on the rate of corrosion in devoid of and containing these compounds was studied and some activated thermodynamic parameters were computed.     

吸电子基团对5-羟色胺衍生物缓蚀性能的增效机理

目的 减缓碳钢在盐酸(HCl)溶液中的腐蚀,揭示吸电子基团(羧基)增效5-羟色胺缓蚀性能的机理。方法 采用动态质量损失、动电位极化曲线与电化学阻抗谱(EIS)考察1mol/L盐酸(HCl)溶液中5-羟色胺(5-HT)与5-羟色氨酸(5-HTP)对20#钢的缓蚀性能。通过吸附等温拟合,明确两种物质在碳钢表面的吸附行为本质。借助形貌观察,验证5-HT与5-HTP对碳钢的缓蚀性能。基于密度泛函理论(DFT),计算并比较两种物质的差分电荷密度。结果 5-HT与5-HTP均可有效减缓20#钢在1mol/L HCl溶液中的腐蚀速率,缓蚀率与添加浓度和环境温度密切相关。298K下添加1mmol/L 5-HT与5-HTP时,缓蚀率分别达到92.19%与95.76%。极化曲线结果显示,向腐蚀介质中加入两种物质后,腐蚀电流密度均降低。EIS结果表明,添加5-HT与5-HTP后,界面电荷转移电阻得到提升。两种物质在碳钢表面的吸附符合Langmuir等温吸附模型。对比动力学与阻抗参数发现,HCl溶液中,5-HTP对20#钢的缓蚀性能优于5-HT。DFT计算结果显示,5-HT质子化位点呈缺电子状态,而质子化5-HTP的电子密度均匀分布于整个分子骨架。结论 羧基的吸电子效应可促进5-HTP分子中富电子区域将盈余电荷流入质子化位点,从而使电子密度均匀分布于分子骨架。均匀的电子密度分布有利于5-HTP以平行构型吸附于碳钢表面,最大限度覆盖活性位点,并高效缓蚀。     

Aminopyrimidine derivatives as inhibitors for corrosion of 1018 carbon steel in nitric acid solution

The effect of some aminopyrimidine derivatives on the corrosion of 1018 carbon steel in 0.05 M HNO₃ solution was studied using weight loss and polarization techniques. The percentage inhibition efficiency was found to increase with increasing concentration of inhibitor and with decreasing temperature. The addition of KI to aminopyrimidine derivatives enhanced the inhibition efficiency due to synergistic effect. The inhibitors are adsorbed on the steel surface according to Temkin isotherm. Some thermodynamic functions were computed and discussed. It was found that the aminopyrimidine derivatives provide a good protection to steel against pitting corrosion in chloride containing solutions.     

Synthesis of some aromatic nitro compounds and its applications as inhibitors for corrosion of carbon steel in hydrochloric acid solution

The inhibition effect of some synthetic aromatic nitro compounds on the corrosion of carbon steel in 1 M HCl solution was studied using galvanostatic and potentiodynamic anodic polarization measurements. The percentage inhibition efficiency was found to increase with increasing the concentration of inhibitors and decreasing of temperature. Polarization data indicated that the additives acted as mixed-type inhibitors meaning that these compounds reduced the anodic dissolution of carbon steel and retard the cathodic hydrogen evolution reaction. Inhibition was interpreted in view of formation of insoluble complex adsorbed on the metal surface. The formation of complex was confirmed by UV-spectra. The adsorption of these compounds was found to obey Langmuir adsorption isotherm. Activation energy and some activated thermodynamic parameters were computed and discussed. It was found that these additives provide good protection to carbon steel against pitting corrosion in chloride-containing solution.     

盐酸溶液中阳离子Gemini表面活性剂在碳钢表面的吸附与缓蚀性能研究

 合成并用元素分析和核磁共振(1H-NMR)表征了阳离子Gemini表面活性剂1,2-双亚甲基-双(十烷基二甲基溴化铵)和1,2-双亚甲基-双(十二烷基二甲基溴化铵)(分别简写为10-2-10和12-2-12)，并用失重法研究了1M盐酸溶液中该类表面活性剂在碳钢表面的吸附行为及其缓蚀性能.实验结果表明，其缓蚀机理为表面活性剂在钢铁表面的吸附形成单分子膜，从而阻碍了盐酸对钢铁的侵蚀，其缓蚀效率随着表面活性剂浓度的增加而增加，当表面活性剂浓度接近其临界胶束浓度时达到最大，理论计算表明，在研究的浓度范围内，盐酸溶液中该类Gemini表面活性剂在碳钢表面的吸附行为符合Langmuir吸附等温式.      

Investigation of the inhibitive effect of p-substituted 4-(N,N,N-dimethyldodecylammonium bromide)benzylidene-benzene-2-yl-amine on corrosion of carbon steel pipelines in acidic medium

The corrosion inhibition efficiency of carbon steel pipelines in 1 M HCl by the synthesized novel surfactants was studied using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements at 20 °C. Temperature effect on the corrosion behaviour was studied at a temperature range from 20 to 80 °C. The results showed that all synthesized inhibitors were good inhibitors and their inhibition efficiencies were significantly increased with increasing both the concentration and temperature. The inhibition efficiency was also influenced by the type of the functional groups substituted on the benzene ring. Polarization curves revealed that the studied inhibitors represent a mixed-type of inhibitors. An equivalent circuit is suggested based on analysis of EIS data. Adsorption of inhibitors was found to obey Langmuir isotherm and was chemisorption.     

Corrosion inhibition of mild steel in hydrochloric acid solution by Schiff base furoin thiosemicarbazone

A heterocyclic Schiff base furoin thiosemicarbazone was tested for its corrosion inhibition towards mild steel in 1 M HCl solution using weight loss, Tafel polarization and electrochemical impedance spectroscopy techniques. Furoin thiosemicarbazone revealed good corrosion inhibition efficiency even at low concentrations towards mild steel in HCl medium. Comparison of corrosion inhibition efficiency of Schiff base and its parent amine and effect of temperature on inhibition efficiency were also investigated. The adsorption of furoin thiosemicarbazone on mild steel surface obeys Langmuir isotherm.     

盐酸介质中N,N′-二（二苯基膦基）-1-苯乙胺对碳钢的缓蚀性能研究

目的对N,N'-二(二苯基膦基)-1-苯乙胺(NPM)的合成、结构表征及其在盐酸介质中对碳钢的缓蚀性能进行研究。方法用红外光谱、元素分析和熔点测试等方法对NPM的结构进行表征,采用静态失重法、动电位极化曲线法和电化学阻抗法研究NPM在盐酸介质中对碳钢的缓蚀作用,研究腐蚀体系温度、HCl浓度、NPM浓度和腐蚀体系静置时间对NPM缓蚀率的影响,探讨NPM在碳钢表面上的吸附机理。结果动电位极化曲线法研究结果表明NPM是一种混合型缓蚀剂。NPM的缓蚀率随NPM浓度的增加而增大,当NPM的质量浓度为140 mg/L时,NPM在25℃的1.0 mol/L HCl溶液中的缓蚀率达到94.71%;NPM的缓蚀率随腐蚀体系温度的升高而降低,随HCl浓度的增大而减小,但随腐蚀体系静置时间的延长缓蚀率逐渐增大。NPM在碳钢表面的吸附符合Langmuir吸附等温方程式,属于自发进行的物理和化学吸附。结论所合成的化合物NPM是一种高效的混合型有机缓蚀剂。     

吐温-40 与植酸复配对碳钢的缓蚀作用

目的提高0.5 mol/L HCl中植酸对热轧碳钢(HRCS)的缓蚀性能。方法用失重法和电化学阻抗法测试植酸、吐温-40以及复配缓蚀剂的缓蚀效率,从热力学和动力学方面分析复配缓蚀剂的作用机制。结果失重法测试表明,植酸和吐温均对热轧碳钢有一定缓蚀作用。当293 K,植酸质量浓度为0.3g/L时,缓蚀效率达到69.1%,在质量浓度为0.8 g/L时缓蚀效率下降为9.6%;吐温-40的缓蚀效率随着质量浓度的增大而增大,0.8 g/L时达到73.4%。在0.5 mol/L盐酸中加入0.05 g/L吐温-40后,复配缓蚀剂的缓蚀效率随着质量浓度的增加而增大,且优于植酸和吐温-40单独使用,表现出协同效应。电化学测试得到了相同的结论,表明复配缓蚀剂在碳钢表面产生自发的Langmuir吸附,使碳钢腐蚀反应的活化能增大,是熵减少的放热过程。结论吐温-40和植酸在盐酸中对热轧碳钢的腐蚀有缓蚀协同作用。