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1.
席夫碱是由伯胺与活性羰基缩合而成的含有甲亚胺活性基团-RC=N-的一类有机化合物,能在金属表面发生化学吸附反应而形成结构稳定、排列紧密有序的自组装膜(SAMs);SAMs是一种有缓蚀性能的单分子膜,对基底金属有良好的防腐蚀作用.本文综述了近年来席夫碱类自组装膜的制备方法及自组装膜的表征技术,进一步概述了分子模拟及拓扑结...  相似文献   

2.
合成了新型Schiff碱化合物香兰素缩3,4-二氨基苯甲酸(V-dba)。采用红外光谱对其结构进行了表征。研究了V-dba在45#钢电极表面的组装工艺,采用电化学阻抗谱(EIS)和极化曲线方法研究了V-dba自组装膜对45#钢缓蚀性能的影响。结果表明,改变组装时间和组装浓度均对Schiff碱的缓蚀效率产生影响。随着组装浓度的增大,自组装膜增大Schiff碱对钢的缓蚀效率。最佳工艺条件为:组装时间12h,组装摩尔浓度0.360mmol.L-1,缓蚀效率最高。  相似文献   

3.
某些含氮化合物缓蚀作用的量子化学研究   总被引:11,自引:3,他引:8  
用量子化学方法计算了苯胺及其卤代和甲基取代衍生物,N-苯基十二烷基胺及其甲基取代物等含氮化合物的电子结构,行讨论了在酸性介质中对软钢的缓蚀效果与其电子结构的关系。较好地解释了相同取代基不同取代位置以及同一取代位置不同取代基化合物的缓蚀率差异。从电子转移的角度说明了含氮有机化合物的缓蚀机理。为研制效果更好的有机缓蚀剂提供了有用的信息。  相似文献   

4.
张哲  阮乐  李秀莹  黄晓东 《表面技术》2017,46(1):193-199
目的通过自组装技术在碳钢表面得到3-氨基-1,2,4-三氮唑及3种3-氨基-1,2,4-三氮唑并芳香醛类希夫碱的三种自组装膜,提高碳钢在0.5 mol/L HCl溶液中的缓蚀性能。方法采用电化学方法如电化学阻抗谱、tafel极化曲线等研究席夫碱类自组装膜在盐酸中的电化学参数,如阻抗变化、腐蚀电位、腐蚀电流。采用XPS方法对自组装膜的成分进行表征。结果计算自组装膜在盐酸溶液中的最高缓蚀效率达到92.72%,XPS测试表明自组装分子与金属原子以化学键的方式结合。结论 3-氨基-1,2,4-三氮唑及3种3-氨基-1,2,4-三氮唑并芳香醛类希夫碱自组装膜均对碳钢在盐酸中有良好的缓蚀性能,缓蚀效率的大小与分子结构有关,分子中的O、N杂原子、卤素基团、三唑环及苯环等有利于自组装膜的形成。  相似文献   

5.
席夫碱主要指含有亚胺或甲亚胺特征基团 (—RC=N—) 的一类有机化合物。目前席夫碱缓蚀剂具有良好的应用前景,被广泛地应用于工业生产中。本文介绍了近年来国内外席夫碱缓蚀剂的发展概况,阐述了席夫碱缓蚀剂的制备方法及作用机理,并对席夫碱缓蚀剂的发展趋势进行了展望。  相似文献   

6.
谷氨酸及其衍生物在304不锈钢表面的自组装膜   总被引:2,自引:0,他引:2  
采用电化学阻抗谱、极化曲线、量子化学和分子动力学,研究了谷氨酸、焦谷氨酰胺、焦谷氨酸三种自组装膜在0.5 mol/L硫酸溶液中对304不锈钢的缓蚀性能.结果表明,三种缓蚀剂均为阴极型缓蚀剂,对不锈钢具有较好的缓蚀作用;在0.02 mol/L的浓度下,随着组装时间的延长,自组装膜对不锈钢的缓蚀效率也相应增强.它们的缓蚀能力与理论EHOMO越高、能量间隙△E越低.自组装分子成键能力越强、缓蚀效率越高相一致.三种缓蚀剂分子中的氮原子、氧原子可以与铁原子形成化学键,发生化学吸附.缓蚀能力依次为:焦谷氨酸>焦谷氨酰胺>谷氨酸.  相似文献   

7.
    用(E)-3-(咪唑基-1-甲基)肉桂酸分子在铁表面形成自组装膜,并用电化学阻抗谱和极化曲线研究不同组装时间对自组装膜缓蚀效果的影响,并运用量子化学计算初步探讨(E)-3-(咪唑基-1-甲基)肉桂酸在铁表面的缓蚀机理.结果表明,(E)-3-(咪唑基-1-甲基)肉桂酸分子能自发吸附在铁表面形成自组装膜,随着组装时间的增加,自组装膜对铁的缓蚀效率也相应增加.  相似文献   

8.
碳钢表面自组装邻氧乙酸苯甲醛缩间氨基苯甲酸二钾席夫碱(K_2L2)缓蚀膜。采用极化曲线、电化学阻抗谱和扫描电镜研究了自组装缓蚀膜在模拟实际工作环境中对碳钢的缓蚀性能。结果表明:矿化度、温度、pH、流动状态和H_2S含量对自组装缓蚀膜在CO_2饱和油田水中的缓蚀性能具有一定的影响,但仍有较高的缓蚀率,当油田水中H_2S质量分数为200mg/L时,缓蚀率达到80.0%。  相似文献   

9.
取代基咪唑啉分子结构与缓蚀性能的实验研究   总被引:8,自引:0,他引:8  
合成了四个取代基咪唑啉化合物,并进行IR和UV分析,用电化学和失重法测试了化合物Ⅰ-Ⅳ的缓蚀率,发现四个取代基咪唑啉化合物的缓蚀率依次增大,从实验的角度探索了取代基与缓蚀性能的关系,实验结果和理论分析表明:具有P-π共轭体系的咪唑啉化合物并同时在环上引入供电子基团,特别是具有共轭体系的取代芳烃,能增强咪唑啉型化合物的缓蚀性能。  相似文献   

10.
用咪唑啉水溶液在镁合金(AZ91D)电极表面制备了自组装单分子膜,研究了该组装膜在0.2 mol/L NaCl中对AZ91D的缓蚀作用.通过接触角、FT-IR、EIS和线性极化等方法对自组装膜的形成过程和保护效率进行了研究,得出最佳的咪唑啉组装液浓度为5×10-4mol/L和最佳组装时间为72 h下的缓蚀效率.  相似文献   

11.
合成了3种水杨醛类吡啶甲酰腙席夫碱化合物(L1、L2、L3)。以失重法、电化学方法、扫描电镜和分子动力学模拟方法考察它们在海水中对低碳钢的缓蚀行为,探讨其缓蚀机理和吸附行为。结果表明,3种酰腙席夫碱属混合型缓蚀剂,在海水中均能有效的抑制碳钢的腐蚀。缓蚀能力的大小遵循L3>L2>L1,失重实验显示当L3浓度为2.8×10-4mol/L时,缓蚀率最大为87.8%。其在碳钢表面上的吸附符合Langmuir吸附等温式,是自发放热吸附过程,吸附机理为化学吸附,扫描电镜和分子动力学模拟结果也证明了3种酰腙席夫碱特别是L3可有效的抑制海水对低碳钢的腐蚀。  相似文献   

12.
The inhibition effect of four new Schiff bases on the corrosion of 304 stainless steel in 1 M HCl has been studied by polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurements. Polarization curves indicated that all studied Schiff bases act as mixed type (cathodic/anodic) inhibitors. The adsorption of the inhibitors was well described by the Langmuir adsorption isotherm and the adsorption isotherm parameters (Kads, ΔGads) were determined at room temperature. Effect of temperature on the efficiency of the corrosion inhibition process was studied and the values of activation energy, pre-exponential factor (λ), enthalpy of activation and entropy of activation were calculated to elaborate the mechanism of corrosion inhibition. Differences in inhibition efficiency between four tested inhibitors are correlated with their chemical structures.  相似文献   

13.
The effect of newly synthesized S2N2-Schiff bases is investigated on stainless steel 304 corrosion in 15% hydrochloric acid. The Tafel curves of the steel in hydrochloric acid containing Schiff bases show inhibition for both cathodic and anodic processes. Moreover, double layer capacitance and charge transfer resistance values are derived from Nyquist plots. The inhibition efficiency of Schiff bases increases with the increase in inhibitor concentration and temperature. Moreover, Langmuir adsorption isotherm is suitable to fit experimental data of the studied inhibitors. Effect of temperature on the efficiency of the corrosion inhibition shows chemisorption of inhibitors on the surface of metal.  相似文献   

14.
王秀阁  蔡明建 《表面技术》2017,46(1):187-192
目的研究不同复配型芳香希夫碱缓蚀剂在油田采出水中对N80碳钢的缓蚀效果。方法采用静态失重和旋转挂片实验比较四种芳香希夫碱的缓蚀速率,采用电化学测试、扫描电镜和EDS手段对N80碳钢进行表征和分析。结果在油田采出水中添加芳香希夫碱复配型缓蚀剂后,试样表面生成以铁、碳、氧元素为主的保护膜,当四种缓蚀剂的添加量达到90 mg/L时,N80碳钢的腐蚀速率下降趋势变化缓慢,a型缓蚀剂的缓蚀效果最好,其用量为90 mg/L时,N80碳钢的腐蚀速率降低到0.0087 mm/a,自腐蚀电位由-0.8112V提高到-0.7345 V,自腐蚀电流由77.79μA下降到5.410μA,缓蚀率可达到93.05%。结论四种希夫碱复配缓蚀剂均有较好的缓蚀性能,缓蚀剂的缓蚀效果顺序为abdc。  相似文献   

15.
The corrosion inhibition of mild steel in 1.0 M HCl solution by four Schiff bases was investigated using weight loss and electrochemical measurements and quantum chemical calculations. All compounds showed >90% inhibition efficiency at their optimum concentrations. The activation energy (Ea) of corrosion and other thermodynamic parameters were calculated to elaborate the mechanism of corrosion inhibition. The adsorption of the inhibitors on the mild steel surface follows Langmuir isotherm model. Polarization studies indicated that all studied inhibitors are mixed type. The computed quantum chemical properties viz., electron affinity (EA) and molecular band gap (ΔEMBG) show good correlation with experimental inhibition efficiencies.  相似文献   

16.
Inhibitory effect of three Schiff bases 2-{[(2-sulfanylphenyl)imino]methyl}]phenol (A), 2-{[(2)-1-(4-methylphenyl)methylidene]amino}-1-benznethiol (B), and 2-[(2-sulfanylphen-yl)ethanimidoyl)]phenol (C) on corrosion of mild steel in 15% HCl solution has been studied using weight loss measurements, polarization and electrochemical impedance spectroscopy (EIS) methods. The results of the investigation show that the compounds A and B with mean efficiency of 99% at 200 mg/L additive concentration have fairly good inhibiting properties for mild steel corrosion in hydrochloric acid, and they are as mixed inhibitor. All measurements show that inhibition efficiencies increase with increase in inhibitor concentration. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. Adsorption of these inhibitors follows the Langmuir adsorption isotherm. Thermodynamic adsorption parameters (Kads, ΔGads) of studied Schiff bases were calculated using the Langmuir adsorption isotherm. Activation parameters of the corrosion process such as activation energies, Ea, activation enthalpies, ΔH, and activation entropies, ΔS, were calculated by the obtained corrosion currents at different temperatures. Obvious correlation was found between the corrosion inhibition efficiency and the calculated parameters. The obtained theoretical results have been adapted with the experimental data.  相似文献   

17.
The corrosion behavior of carbon steel in 0.5 M HCl solution in the absence and presence of new five Schiff bases of indole derivatives was investigated using electrochemical impedance spectroscopy (EIS), electrochemical frequency modulation (EFM) and potentiodynamic polarization techniques. All the experimental results show that these Schiff bases have excellent corrosion inhibition performance. The polarization curves show that these compounds act as mixed type inhibitors. The adsorption of these Schiff bases on carbon steel surface is consistent with Langmuir adsorption isotherm. The effect of temperature on the rate of corrosion in the absence and presence of these compounds were also studied. Some thermodynamic functions were computed and discussed. The results obtained by the three different electrochemical techniques were in good agreement.  相似文献   

18.
采用极化曲线、电化学阻抗谱、扫描电镜和能谱分析,研究合成的3-吡啶-4-氨基-1,2,4-三唑-5-硫酮席夫碱及其复配物硝酸铈在质量分数为3.5%NaCl溶液中对1060纯铝的缓蚀作用。结果表明:在293 K时席夫碱可有效抑制纯铝在3.5%NaCl溶液中的腐蚀,当席夫碱浓度为0.4 g.L-1时缓蚀率最高,可达76.0%。席夫碱为混合型缓蚀剂,其在1060纯铝表面的吸附符合Langmuir吸附模型,且同时存在物理吸附和化学吸附。0.2 g.L-1席夫碱与0.03 g.L-1硝酸铈复配缓蚀率可达88.2%,二者具有协同缓蚀作用。  相似文献   

19.
有机缓蚀剂的量子化学研究   总被引:33,自引:9,他引:24  
本文概述了缓蚀剂量子化学研究方面的成果。着重讨论了缓蚀性能与量子化学参数以及分子的电荷分布与缓蚀机制间的关系,并分析了质子化作用对分子量化计算结果的影响,最后科述了缓蚀研究使用的量子化学方法。  相似文献   

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