咪唑啉和季铵盐类缓蚀剂对P110S钢的缓蚀作用和机理研究

采用失重法、极化曲线、电化学阻抗谱(EIS)和扫描电镜(SEM)研究了咪唑啉和季铵盐缓蚀剂在H_2S/CO_2环境中对P110S钢的缓蚀作用和缓蚀机理。结果表明,咪唑啉缓蚀剂和季铵盐缓蚀剂均为阳极型缓蚀剂;在120℃,H_2S分压为0.55 MPa、CO_2分压为0.80 MPa的环境中,两种缓蚀剂均有一定的缓蚀作用,能有效抑制P110S钢的腐蚀;添加浓度为200 mg·L~(-1)时,咪唑啉缓蚀剂的缓蚀效率可达87.23%。     

盐酸介质中锌缓蚀剂的研制

采用正交试验方法对喹啉、吖啶、季铵盐类化合物进行复配得到一种盐酸介质中锌的优良缓蚀剂.利用失重法、电化学极化曲线法、扫描电镜对其缓蚀性能进行了评价.结果表明该复合缓蚀剂缓蚀率高,是一种阴极型缓蚀剂,扫描电镜照片显示无点蚀、晶间腐蚀等非均匀腐蚀现象.     

咪唑啉与硫脲在CO2腐蚀体系中的缓蚀协同作用机理

采用极化曲线和电化学阻抗技术(EIS)研究了油酸基咪唑啉季铵盐(OIMQ)与硫脲(TU)对Q235碳钢在CO2饱和盐水溶液中的缓蚀协同效应。结果表明,TU对碳钢腐蚀的阴极过程和阳极过程都有强烈的抑制作用,而OIMQ是一种以抑制阳极为主的混合型缓蚀剂。二者复配使用,可以有效降低使用浓度,表现出优异的缓蚀协同效应。OIMQ与TU在碳钢表面形成了一层双层结构的缓蚀剂吸附膜,TU可能主要存在于膜的底部,而OIMQ主要存在于膜的顶部,这种结构的缓蚀剂膜一方面阻止了腐蚀性离子的渗透,另一方面也限制了TU分子的脱附。     

CO2饱和NaCl溶液中松香基咪唑啉季铵盐的缓蚀吸附行为

以松香和二乙烯三胺为原料合成了松香基咪唑啉,并采用氯乙酸钠对合成产物进行季铵化改性,得到水溶性松香基咪唑啉季铵盐.通过失重法和电化学方法测试了该季铵盐在60℃的CO2饱和3%NaCl溶液中对Q235钢的缓蚀性能.结果表明,水溶性松香基咪唑啉季铵盐对Q235钢有很好的缓蚀作用,150 mg/L用量时缓蚀率超过90%.该缓蚀剂是一种以阳极抑制为主的缓蚀剂,遵循Langmuir吸附等温式,在钢表面发生自发吸附,存在较强的吸附作用力.     

咪唑啉季铵盐对Q235钢在盐酸溶液中的缓蚀性能

合成了苯乙酸咪唑啉季铵盐(PAIPI)和萘乙酸咪唑啉季铵盐(NAIPI),通过失重法、电化学方法研究了两者在1 mol/L HCl中对Q235钢的缓蚀性能,并探讨了其在Q235钢表面的吸附行为.结果表明,两者在1 mol/LHCl中对Q235钢均为阳极型缓蚀剂,其中NAIPI对Q235钢的缓蚀性能优于PAIPI;两者在Q235钢表面均是单层吸附,属于物理吸附.     

含噻二唑季铵盐表面活性剂的合成及缓蚀杀菌性能研究

结合杂环化合物和季铵盐表面活性剂用作缓蚀剂和杀菌剂的结构特点,合成了含噻二唑杂环的季铵盐表面活性剂(MTOTB),并采用1HNMR、ESI-MS和FT-IR对其结构进行表征.采用表面张力法研究其表面活性,采用电化学测试和表面分析的方法研究其在含硫酸盐还原菌(SRB)的模拟海水中对碳钢的缓蚀性能.结果 表明,MTOTB在...     

喹啉季铵盐酸化缓蚀剂对超级13Cr不锈钢电化学行为的影响

研究了喹啉季铵盐对超级13Cr不锈钢在1 mol/L盐酸溶液中电化学行为的影响,并分析了温度、卤族阴离子类型和浓度对于喹啉季铵盐缓蚀效率的影响及机理。研究表明,喹啉季铵盐属于抑制阳极反应为主的混合型缓蚀剂,温度的升高会促进喹啉季铵盐的脱附过程,使其保护作用降低。卤族阴离子协同作用效果的顺序为：I^->Br^->Cl^-。随着I^-浓度的升高,其协同作用效果提高。加入0.005 mol/L以上浓度的KI,喹啉季铵盐的缓蚀率可达99%以上。     

混合酸咪唑啉缓蚀剂的合成及缓蚀性能研究

本文采用二乙烯三胺、环烷酸(85%)、油酸为原料,通过咪唑啉季铵化反应,合成一种油田用缓蚀剂。采用红外光谱扫描,通过特征峰的分析,验证合成产物确为咪唑啉季铵盐。通过挂片失重实验,测试了混合酸配比、不同反应温度下所得到药剂的缓蚀性能,确定反应的最佳工艺条件;通过电化学研究了该药剂的增效剂、最佳加药浓度及缓蚀机理。结果表明:在环烷酸:油酸=1:0.6、季铵化反应温度为100~110℃的工艺条件下,所得混合酸缓蚀剂的缓蚀效果最佳;该缓蚀剂与硫脲、丙炔醇等具有增效作用。依据电化学弱极化曲线,该缓蚀剂为抑制阳极过程为主的混合型缓蚀剂。     

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.     

咪唑啉季铵盐缓蚀剂的合成及缓蚀行为的研究

本文以复合固体酸作催化剂,以油酸、二乙烯三胺、氯化苄为主要原料合成了咪唑啉季铵盐。用静态失重法、动电位极化曲线法、电化学阻抗法研究其在15%盐酸溶液中对A3钢的缓蚀性能。实验结果表明,缓蚀剂的缓蚀效率随着缓蚀剂浓度的增加而增加但随着温度的升高而减小。缓蚀剂浓度为10g/L时,用静态失重法测其在60℃15%盐酸溶液中的缓蚀效率为99.18%,当缓蚀剂与KI复配时,两者产生良好的协同效应:缓蚀剂与KI质量比为5:1的时候,缓蚀效率为99.7%。该缓蚀剂在A3钢表面的吸附遵循Langmuir吸附等温模型。动电位极化曲线测试表明该缓蚀剂是以抑制阴极为主的混合型缓蚀剂。     

三唑化合物在0.5 mol/L硫酸中对Q235钢的缓蚀作用

合成了一种新型三氮唑化合物:1-苯次乙亚氨基-2-巯基-5-[1-(1,3,4-三氮唑)亚甲基]-1,3,4-三氮唑(PMT),并通过失重试验、动电位极化、电化学阻抗谱及扫描电镜方法研究了其在0.5mol/L硫酸溶液中对Q235碳钢的缓蚀作用。结果表明,该三唑化合物在硫酸中对Q235碳钢有较好的缓蚀效果,是混合型缓蚀剂。     

硫脲-二乙烯三胺缩聚物对混凝土中钢筋的缓蚀作用

用动电位极化曲线及电化学阻抗谱研究了硫脲－二乙烯三胺缩聚物在浊凝土孔隙模拟液及混凝土中对钢筋腐蚀的抑制作用。结果表明它是一种混合型缓蚀风筋的点蚀有较好的抑制作用。在模拟液中添加１％的该缓蚀剂就可以使对氯离子的容忍度从０．０２ｍｏｌ／Ｌ提高到０．１ｍｏｌ／Ｌ。它与ＮａＮｏ３有交好的协同作用。它妈能吸附于钢筋表面,又能提高混凝土密实程度,减缓腐蚀介质向混凝土内的渗透。能谱分析的结果表明它能够富集于钢筋     

Polyoxadiazole-based coating for corrosion protection of magnesium alloy

In this study, polyoxadiazole-based coatings were molecularly designed by attaching two different functional groups, i.e., diphenyl-ether and diphenyl-hexafluoropropane, in the main polymer chain for the purpose of low water permeability and eventually for high corrosion protection of AM50 magnesium alloy. Potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) were used to evaluate the coating performance of the two polymers. Electrochemical experiments showed that POD-6FP (poly(4,4′-diphenyl-hexafluoropropane-1,3,4-oxadiazole)) coated alloy exhibited 3-4 orders of magnitude higher corrosion resistance as compared to the POD-DPE (poly (4,4′-diphenyl-ether-1,3,4-oxadiazole)) coated alloy. The high coating performance of the POD-6FP polymer can be attributed to the hydrophobic group attached to the polyoxadiazole chain.     

Inhibition of copper corrosion in acidic chloride pickling solutions by 5-(3-aminophenyl)-tetrazole as a corrosion inhibitor

Inhibition of copper corrosion in acidic chloride pickling (0.5 M HCl) solutions by 5-(3-Aminophenyl)-tetrazole (APT) as a corrosion inhibitor has been studied using potentiodynamic polarization, chronoamperometry (CA), electrochemical impedance spectroscopy (EIS), weight-loss and Raman spectroscopy investigations. Electrochemical measurements showed that the presence of APT and the increase of its concentration significantly decrease the cathodic, anodic, and corrosion currents as well as corrosion rates. This effect also decreases the dissolution currents of copper at 200 mV vs. Ag/AgCl, and greatly increases surface and polarization resistances and inhibition efficiency as indicated by CA and EIS measurements. Weight-loss data revealed that the corrosion rate of copper decreases to a minimum and the inhibition efficiency increases to a maximum in the presence of APT and upon increasing of its concentration even after 72 h of copper coupons immersion. Comparing the Raman spectrum obtained on the copper surface after its immersion in HCl solution containing 1.0 mM APT for 72 h to the spectrum obtained for the solid APT alone indicated that APT molecules inhibit the corrosion of copper via their adsorption onto its surface.     

Poly(4-vinylpyridine-poly(3-oxide-ethylene) tosyle) as an inhibitor for iron in sulphuric acid at 80 °C

The influence of poly(4-vinylpyridine-poly(3-oxide-ethylene) tosyle) P4VPPEO5000Ts, on the corrosion inhibition of iron in molar sulphuric acid solution is studied using weight-loss, polarisation resistance, potentiodynamic and EIS measurements. P4VPPEO5000Ts is an excellent inhibitor and its inhibition efficiency increases with the increase of concentration to attain 100% since 2.5 × 10⁻⁸ M. Potentiodynamic polarisation studies clearly reveal that it acts as a mixed-type inhibitor. The polymer studied reduces the corrosion rates. E% values obtained from weight-loss, corrosion current density, polarisation resistance and EIS methods are in good agreement. Adsorption of this compound on iron surface has an S-shaped adsorption isotherm with two consecutive steps.     

炼油厂闲置设备保护用气相缓蚀剂的研制

在实验室制得了V2复合型气相缓蚀剂，采用静态、动态粉末法、密闭空间挥发减量试验、现场保护试验等方法进行了性能评价，并采用模拟大气腐蚀状态的电化学测试技术对其缓蚀机理进行了初步研究。结果表明，V2是一种性能优良、有实用前景的钢用气相缓蚀剂。     

Inhibitive action of some plant extracts on the corrosion of steel in acidic media

The effect of extracts of Chamomile (Chamaemelum mixtum L.), Halfabar (Cymbopogon proximus), Black cumin (Nigella sativa L.), and Kidney bean (Phaseolus vulgaris L.) plants on the corrosion of steel in aqueous 1 M sulphuric acid were investigated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. EIS measurements showed that the dissolution process of steel occurs under activation control. Potentiodynamic polarization curves indicated that the plant extracts behave as mixed-type inhibitors. The corrosion rates of steel and the inhibition efficiencies of the extracts were calculated. The results obtained show that the extract solution of the plant could serve as an effective inhibitor for the corrosion of steel in sulphuric acid media. Inhibition was found to increase with increasing concentration of the plant extract up to a critical concentration. The inhibitive actions of plant extracts are discussed on the basis of adsorption of stable complex at the steel surface. Theoretical fitting of different isotherms, Langmuir, Flory-Huggins, and the kinetic-thermodynamic model, were tested to clarify the nature of adsorption.     

Surface modification of stainless steels: green technology for corrosion protection

Many methods of corrosion protection rely on toxic chemicals such as hexavalent chromium (Cr⁶⁺), which is the species responsible for protection in conversion coatings, anodizing baths and as a pigment in polymer coatings. Despite many attemps to replace Cr⁶⁺ and other harzardous chemicals in corrosion protection, very little progress has been made. Passive layers containing Ce and Mo have already been formed on materials such as A17075 and A12024, and their corrosion behaviour has been shown to improve by inhibition of both anodic and cathodic reaction. In this work the results of applying these coatings to SS304 and 316 will be presented. The layers were studied by electrochemical impedance spectroscopy (EIS), X-ray photo-electron spectroscopy (XPS), and the corrosion behaviour was followed by EIS and d.c. current methods.     

医用 316L 不锈钢表面多巴胺 / BSA 复合膜缓蚀性能研究

目的研究医用316L不锈钢表面组装多巴胺/牛血清白蛋白分子(BSA)复合膜的缓蚀性能。方法采用浸泡法在医用316L不锈钢表面制备以多巴胺自组装膜为桥接层的多巴胺/BSA复合双层自组装膜,通过动电位扫描、交流阻抗测试,SEM,EDX等手段分析BSA组装液质量浓度对复合双层自组装膜吸附行为及耐蚀性能的影响。结果在合适的自组装条件下可获得具有缓蚀效果的复合双层膜。BSA质量浓度过高和过低均对缓蚀性能有不利影响,当BSA质量浓度为40 g/L时,复合双层膜对生理盐水环境中316L不锈钢取得最佳缓蚀效率,缓蚀效率由单层多巴胺的62.4%增加至83.9%。结论多巴胺成功嫁接BSA分子,使其吸附在不锈钢表面,和单层BSA吸附相比,其吸附量大大提高,表明对于316L不锈钢人体植入材料,可以利用多巴胺桥接BSA获得兼具生物活性和耐腐蚀性的改性表面。     

The role of acid anion on the inhibition of the acidic corrosion of steel by lupine extract

The inhibitive effect of lupine (Lupinous albus L.) extract on the corrosion of steel in aqueous solution of 1 M sulphuric and 2 M hydrochloric acids was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Potentiodynamic polarization curves indicated that the lupine extract acts as a mixed-type inhibitor. EIS measurements showed that the dissolution process is under activation control. The inhibition efficiency of the extract obtained from impedance and polarization measurements was in a good agreement and was found to increase with increasing concentration of the extract. The obtained results showed that, the lupine extract could serve as an effective inhibitor for the corrosion of steel in acid media and the extract was more effective in case of hydrochloric acid. Theoretical fitting of the corrosion data to the kinetic-thermodynamic model was tested to show the nature of adsorption.