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.      

Gemini双季铵盐捕收剂BDDA和EDDA对高岭石、叶腊石、伊利石浮选行为的比较及机理

采用了新型Gemini双季铵盐捕收剂丁烷-1,4-双十二烷基二甲基溴化铵（BDDA）和乙烷-1,2-双十二烷基二甲基溴化铵（EDDA）对比研究了其对高岭石、叶腊石、伊利石的浮选行为及作用机理。单矿物试验结果表明,在广泛的pH范围内,新型Gemini双季铵盐捕收剂BDDA和EDDA对三种铝硅酸盐矿物具有优异的捕收性能,且BDDA的捕收能力强于EDDA。红外光谱和动电位研究表明,Gemini双季铵盐捕收剂对三种铝硅酸盐矿物的作用机理为静电吸附和氢键作用。采用DFT密度泛函理论,在B3LYP／6—31G（d）水平上对捕收剂阳离子BDDA2＋和EDDA2＋进行量化计算,结果表明BDDA的捕收能力强于EDDA。这与单矿物浮选结果、动电位测定结果一致。     

十六烷基二甲基乙基溴化铵在硫酸介质中对Q235钢的缓蚀性能研究

采用静态失重法,动电位极化曲线法和电化学阻抗法研究了十六烷基二甲基乙基溴化铵 (CDAB) 在硫酸介质中对Q235钢的缓蚀行为,并探讨了其对Q235钢的缓蚀作用机理.结果表明,在25 ℃下,缓蚀率随CDAB浓度增大而增大,在浓度仅为10 mgL^-1时,失重缓蚀率达85%左右.极化曲线实验结果显示,CDAB是一种以控制阳极反应为主的混合型缓蚀剂,且静态失重法,动电位极化曲线法和电化学阻抗法实验结果相一致.CDAB在Q235钢表面的吸附服从Kastening-Holleck吸附等温模型;CDAB的添加显著增大了腐蚀反应的活化能,有效抑制了腐蚀反应的进行.     

吡啶嗡离子衍生物的缓蚀作用及其吸附模型

用线性极化曲线法研究了N 癸基吡啶溴化铵 (DP) /N 癸基 3 羟基吡啶溴化铵 (D3OP)和N 癸基 3 羧基吡啶溴化铵 (D3CP)在 5 %氨基磺酸中对铁的缓蚀作用及其吸附模型。结果表明 :它们对 5 %氨基磺酸中的铁具有良好的缓蚀作用 ,在吡啶环上引入合适的取代基能提高吡啶嗡离子的缓蚀效果。它们在铁表面的吸附主要为物理吸附 ,其吸附遵循Langmuir吸附等温式 ;随着温度和使用浓度的提高 ,其缓蚀性能加强 ;三种缓蚀剂缓蚀能力大小为D3CP >D3OP >DP。     

N—烷基月桂酰胺对硫酸溶液中碳钢的缓蚀行为

采用电化学的失重法研究Ｎ－烷基月桂酰胺对硫酸溶液中碳钢腐蚀的缓蚀行为和吸附规律。实验表明，其缓蚀性能优良，主要属以阻滞阳极过程为主的缓蚀剂，吸附过程为放热反应，属化学吸附，在不同吸附阶段分别遵循Ｔｅｍｋｉｎ和Ｆｒｕｍｋｉｎ吸附等温式。     

含氮有机物在盐酸溶液中对锌的缓蚀作用

采用失重法研究了在0．8mol／dm^3盐酸中，盐酸吖啶和溴代十六烷基吡啶对锌的缓蚀作用，求得相关吸附热力学参数。结果表明二者均对锌表现出较强的缓蚀作用，盐酸吖啶在锌表面的吸附属于放热反应，而溴代十六烷基吡啶在锌表面的吸附属于吸热反应。     

氯代十六烷基吡啶在铝电极上电化学和SERS研究

用电化学和SERS谱研究了氯代十六烷基吡啶在铝电极上的吸附,发现氯代十六烷基吡啶是一种阴阳极混合抑制型几何覆盖缓蚀剂,平卧吸附在电极表面上.     

氯代十六烷基吡淀在铝电极上电化学和SERS研究

用电化学和ＳＥＲＳ谱研究了氯代十六烷基吡啶在铝电极上的吸附，发现氯代十六烷基吡啶是一种阴阳极混合抑制型几何覆盖缓蚀剂，平卧吸附尖电极表面上。     

二元羧酸对碳钢的缓蚀作用与其分子结构的关系

前言羧酸盐是一种有用的缓蚀剂,它们对金属腐蚀的抑制作用已有研究报道。但关于二元羧酸对中性或弱碱性介质中碳钢的缓蚀能力和它们在电极/溶液界面的吸附行为未见系统研究报道。本工作研究分子结构对烷链二元羧酸缓蚀能力和吸附能力的影响,提出了二元羧酸在碳钢/溶液界面的可能吸附模型。     

十六烷基二甲基乙基溴化铵与 NH4 SCN 缓蚀协同效应

目的研究十六烷基二甲基乙基溴化铵(CDAB)与NH4SCN在硫酸介质中对Q235钢的缓蚀协同效应,并探讨其缓蚀机理和性能,以期为工业实际生产提供理论数据。方法运用失重法研究CDAB质量浓度与缓蚀率的关系,通过失重法、动电位极化曲线法和交流阻抗法分析CDAB与NH4SCN复配后的缓蚀率和缓蚀机理。结果仅添加CDAB时,缓蚀率随着CDAB质量浓度增大而增大,但缓蚀性能并不显著,当质量浓度为10 mg/L时缓蚀率仅为85.07%;当CDAB与30 mg/L的NH4SCN复配后,缓蚀率显著提高到96.73%,能有效抑制Q235钢在0.5 mol/L硫酸介质中的腐蚀。极化试验结果显示,该复配缓蚀剂是一种以控制阳极反应为主的混合型缓蚀剂,缓蚀率随CDAB质量浓度增大而增大,与交流阻抗法、失重法试验结果相一致。复配缓蚀剂在Q235钢表面的吸附服从Langmiur吸附等温模型,吸附吉布斯自由能ΔG0=-48.33 k J/mol,为自发吸附。结论 CDAB与NH4SCN在0.5 mol/L硫酸介质中具有优异缓蚀协同效应,能有效抑制腐蚀介质对Q235钢在的腐蚀,复配缓蚀剂具有较高的缓蚀率。     

盐酸体系不锈钢缓蚀剂的开发

采用失重法和扫描电镜法,测定了五种缓蚀剂对浸没于8%盐酸介质中不锈钢的缓蚀作用,确定了在盐酸体系中对不锈钢具有较好缓蚀性的单组分、二元和三元缓蚀剂配方.实验结果表明:咪唑啉,十六烷基三甲基溴化铵具有较好的缓蚀效果;十六烷基三甲基溴化胺在使用浓度为700 mg/L时,缓蚀率为90.0%;十六烷基三甲基溴化铵与三乙醇胺、咪唑啉及硫脲复配后,缓蚀剂各组分浓度为单组分最佳浓度一半的情况下,缓蚀率分别达到为91.8%、90.8%和89.7%,缓蚀剂的成本得以下降;三元复配缓蚀剂中,咪唑啉-硫脲-乌洛托品和咪唑啉-硫脲-三乙醇胺两种缓蚀剂的缓蚀率均高于90%,且使用成本低,是理想的盐酸体系不锈钢缓蚀剂.扫描电镜图像表明,添加了缓蚀剂的金属表面腐蚀轻微,表面光滑,且不存在明显的点蚀倾向,缓蚀剂对金属表面起到很好的保护作用.     

The adsorption and corrosion inhibition of some cationic gemini surfactants on carbon steel surface in hydrochloric acid

The adsorption and corrosion inhibition of the gemini surfactants 1,2-ethane bis(dimethyl alkyl (C_nH_2n+1) ammonium bromide) (designated as n−2−n, n=10, 12 and 16) on the steel surface in 1 M hydrochloride acid were studied using the weight loss method. It was found that the adsorption of the gemini surfactants on the steel surface is the main reason to cause the steel corrosion inhibition in hydrochloride acid, and the inhibition efficiency increases with the increase of surfactant concentration and reaches the maximum value near the CMC. A possible adsorption model of gemini surfactant onto the metal surface was also discussed.     

土酸溶液中苯扎溴铵对碳钢的缓蚀作用研究

采用失重法和电化学极化曲线研究了不同温度下苯扎溴铵对5%的土酸溶液中碳钢的缓蚀作用。实验结果表明,苯扎溴铵在碳钢表面产生单分子层吸附,并且满足Langmuir吸附规律;吸附过程为放热过程,随着温度的升高,吸附能力减弱,缓蚀效率下降;苯扎溴铵为混合型缓蚀剂。     

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.     

Adsorption and Corrosion Inhibition Behavior of Polyethylene Glycol and Surfactants Additives on Mild Steel in H2SO4

The adsorption and corrosion inhibition behaviors of polyethylene glycol (PEG) alone and in the presence of surfactants sodium dodecyl benzene sulfonate and cetyltrimethyl ammonium bromide on mild steel in 0.1 M H₂SO₄ in temperature range of 30-60 °C was investigated using weight loss method, solvent analysis of iron ions, scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDAX), atomic force microscopy (AFM) and determination of kinetic/thermodynamic parameters. The inhibition efficiency (IE) of PEG increased with increasing concentration showing a maximum IE of 86.91% at 30 °C at 25 ppm but decreased with increasing temperature. Inhibiting action of PEG is synergistically enhanced on addition of small amount of surfactants. Surface morphology of the corroded mild steel specimen as evaluated by SEM, EDAX and AFM confirmed the existence of an adsorbed protective film on the mild steel surface. The calculated thermodynamic/kinetic parameters reveal that adsorption process is spontaneous and obey Langmuir adsorption isotherm.     

Inhibiting effects of some mercapto-triazole derivatives on the corrosion of mild steel in 1.0 M HCl medium

The effect of some mercapto-triazole derivatives synthesized in the laboratory containing different hetero atoms and substituents in the organic structures on the corrosion and hydrogen permeation of mild steel in 1.0 M HCl was investigated by weight loss and various electrochemical techniques. Results obtained reveal that all the mercapto-triazole derivatives perform excellently as corrosion inhibitors for mild steel in 1.0 M HCl. Potentiodynamic polarization studies have shown that all these compounds suppress both the anodic and cathodic process and they behave as mixed-type inhibitors. Double layer capacitance and charge transfer resistance values were derived from Nyquist plots obtained from AC impedance studies. Changes in impedance parameters are indicative of the adsorption of these compounds on the metal surface. The inhibition efficiency mainly depends on the nature of the investigated compounds. The values of the inhibition efficiency calculated from these techniques are in reasonably good agreement. The extent of reduction of hydrogen permeation current through mild steel surface was studied by the hydrogen electropermeation technique. The adsorption of these compounds on mild steel surface is found to obey Langmuir adsorption isotherm. The free energy of adsorption for inhibiting process was determined on the basis of Langmuir adsorption isotherm.     

Understanding the effect of surfactant aggregation on corrosion inhibition of mild steel in acidic medium

Corrosion inhibition by surfactant molecules is related to the surfactant's ability to aggregate at interfaces and in solution. Understanding the factors that affect aggregation as well as the state of aggregation of surfactant molecules on metal surfaces is, therefore, an important prerequisite to understanding corrosion inhibition by surfactant molecules. This article investigates the relationship between surfactant aggregation and mild steel corrosion inhibition in acidic medium using cetyl pyridinium chloride and cety trimethyl ammonium bromide.     

Synergistic effect between cationic gemini surfactant and chloride ion for the corrosion inhibition of steel in sulphuric acid

Corrosion inhibition of cold rolled steel in 0.5 mol L⁻¹ sulphuric acid by a quaternary ammonium gemini surfactant, l,3-propane-bis(dimethyl dodecylammonium bromide) (designated as 12-3-12), in the absence and presence of chloride ions was investigated at different temperatures. The results revealed significant synergistic effect between gemini 12-3-12 and chloride ions for the corrosion protection of cold rolled steel in sulphuric acid, and that the novel composite inhibitor system containing cationic gemini surfactant and chloride ions was efficient and low-cost for steel corrosion inhibition in sulphuric acid medium, even when concentration of 12-3-12 was as low as 1 × 10⁻⁶ mol L⁻¹. By fitting the obtained experimental data with Langmuir adsorption model and Arrhenius equation, some thermodynamic and kinetic parameters such as adsorption free energy, the apparent activation energy, and the pre-exponential factor were estimated. The adsorption mechanism of the gemini surfactant onto steel surface in acid medium in the absence and presence of chloride ions was also discussed, respectively.