2种癸二酸咪唑啉季铵盐的合成及缓蚀性能评价

合成了2种癸二酸咪唑啉季铵盐癸二酸-水杨酸咪唑啉季铵盐(SSAI)和癸二酸咪唑啉季铵盐(SAI),并采用失重法和电化学方法研究了这2种咪唑啉季铵盐对N80钢在1 mol/L HCl溶液中的缓蚀性能和吸附行为。 结果表明,在1 mol/L HCl溶液中这2种化合物对N80钢均有较好的缓蚀作用,缓蚀效率大小顺序为SSAI＞SAI。 SSAI和SAI均为混合偏阳极型缓蚀剂。 2种化合物在N80钢表面的吸附服从Langmuir吸附等温式,属于化学吸附。     

盐酸中1-苯胺甲基苯并咪唑对碳钢的缓蚀行为

采用静态失重、动电位极化、交流阻抗等技术方法研究了1-苯胺甲基苯并咪唑(PAB)对盐酸介质中N80钢的缓蚀性能,并讨论了PAB在N80钢表面的吸附行为。 结果表明,缓蚀率随着PAB浓度增大而升高,随着温度升高而下降。 极化曲线测试表明PAB是一种混合控制型缓蚀剂。 PAB在N80钢表面的吸附是一个自发、放热、熵增的过程,其行为符合Langmuir吸附等温式。 同时采用量子化学方法对PAB的缓蚀机理做了进一步分析。     

N-异丙基丙烯酰胺与N-烯丙基-1-苯甲酰基-3-苯基-4，5-2H-4-甲酰胺基吡唑共聚物对N80钢片的化学和细菌腐蚀的抑制作用

合成了一种新的腐蚀抑制及广谱抑菌剂：N-异丙基丙烯酰胺（NIPAM）与N-烯丙基-1-苯甲酰基-3-苯基-4,5-2H-4甲酰胺基吡唑(BPCP)的共聚物PNIPAM-Co-PBPCP。 分别采用静态失重法和电化学阻抗谱研究了该共聚物在1 mol/L HCl溶液中对N80钢片化学腐蚀的抑制作用以及共聚物分子在N80钢片表面的吸附行为;采用液体稀释法测定了共聚物对各种菌类的最小抑菌浓度（MIC）。 结果表明,在质量浓度为0.5～7.0 g/L的范围内该共聚物对N80钢片的酸腐蚀的抑制效果随缓蚀剂浓度增大而增强;最大缓蚀效率（90.3％）时的缓蚀剂质量浓度为6.0 g/L,仅为文献报道共聚物用量的1/2左右,为小分子缓蚀剂1-苯甲酰基-3-苯基-4,5-2H-4-羧基吡唑（NABPPAA）用量的1/10。 在以上质量浓度范围内共聚物分子在N80钢片表面的吸附满足Langmuir等温吸附模式,其吸附热为30.4 kJ/mol。 该共聚物具有较高的缓蚀效能热稳定性,在25～80 ℃的范围内缓蚀效率保持在80％以上且无明显变化。 据此可以判断,共聚物分子在N80钢片表面上以化学吸附为主。 结果还表明,共聚物分子具有广谱抑菌性,对大肠杆菌、金黄色葡萄球菌、蜡样芽胞杆菌、枯草芽孢杆菌活菌、铜绿假单胞菌、荧光假单胞菌以及沙门氏菌等多种菌类均具有良好的杀灭效果。     

缓蚀剂膜抑制腐蚀介质扩散行为的分子动力学模拟

采用分子动力学模拟方法研究了4种腐蚀介质粒子(H₂O, H₃O⁺, HS^-和Cl^-)在6种不同烷基链长的1-(2-羟乙基)-2-烷基-咪唑啉缓蚀剂膜中的扩散行为. 计算了腐蚀介质粒子在不同缓蚀剂膜中的扩散系数、膜的自由体积分数、粒子与膜的相互作用能等, 并对缓蚀剂膜抑制腐蚀介质粒子扩散行为的微观机理进行了分析. 计算结果表明, 6种缓蚀剂膜均可有效阻碍腐蚀介质粒子向金属表面的扩散, 从而达到抑制或延缓腐蚀的目的; 随烷基链长的增加, 缓蚀剂膜对腐蚀介质粒子扩散行为的抑制能力逐渐增强; 同种缓蚀剂膜对正负离子H₃O⁺, HS^-和Cl^-比对中性的H₂O分子具有更强的扩散抑制能力.     

咪唑啉缓蚀剂膜抑制腐蚀介质扩散行为的MD研究

采用分子动力学模拟的方法,对5种1-(2-氨乙基)-2-烷基-咪唑啉缓蚀剂[(NH2)C2H4-C3H4N2-CH2(CH2)nCH3,n=5,7,9,11,13]抑制CO2腐蚀的缓蚀机理进行了研究.计算了4种腐蚀介质粒子(H2O,H3O+,Cl-和HCO-3)在不同缓蚀剂膜中的扩散系数,并从自由体积分数、腐蚀介质粒子与缓蚀剂膜的相互作用、膜的自扩散性能等方面对缓蚀剂膜抑制腐蚀介质粒子扩散行为的微观机理进行了分析.扩散系数的计算结果表明:缓蚀剂膜能有效抑制腐蚀介质的迁移,削弱其腐蚀能力;与中性H2O分子对比,缓蚀剂膜对H3O+,Cl-和HCO-3带电离子的扩散具有更强的抑制效果;随烷基链长的增加,5种缓蚀剂膜对腐蚀粒子扩散的抑制能力呈增强趋势.综合分子动力学计算结果,5种缓蚀剂缓蚀性能随着烷基链长的增加逐渐增强,理论评价结论与实验结论相吻合.     

双苯并咪唑衍生物对N80钢的缓蚀效果

选用1,3-双(2-苯并咪唑基)丙烷(BBP),1,3-双(2-苯并咪唑基)-2-氧杂丙烷(DMDB),N,N-双(2-苯并咪唑亚甲基)胺(IDB),1,3-双(2-苯并咪唑基)-2-硫代丙烷(BBMS)4种结构相似的双苯并咪唑衍生物作为N80油管钢缓蚀剂。采用失重法和电化学极化测试分别考察了不同缓蚀剂的缓蚀性能及其与KI复配后在pH=4.5的饱和CO2溶液中对N80钢的缓蚀效果。结果表明,此系列双苯并咪唑衍生物在投加量较小的情况下即对N80钢均具有较好的缓蚀效果,且此系列缓蚀剂既抑制了阳极过程,又抑制了阴极过程,为混合型缓蚀剂。当1,3-双(2-苯并咪唑基)-2-硫代丙烷(BBMS)与KI复配后,缓蚀机理没有发生改变,且缓蚀率明显提高,其浓度均为2mmol/L时,缓蚀率高达95.09%。     

YKI-05缓蚀剂对不同浸没条件下907A钢的缓蚀性能研究

利用动电位极化方法 ,研究了有机膦酸醇酯类缓蚀剂 (YKI_0 5 )对 90 7A钢在天然海水中的缓蚀行为 .实验表明 :静态海水中 ,浓度为 30 0mg/L的YKI_0 5缓蚀剂能在 90 7A钢表面形成稳定的缓蚀膜层 ,是一负催化阴极型缓蚀剂 ,于实验周期内其对 90 7A钢的缓蚀效率可稳定在 90 %左右 ;在周期性间歇浸没情况下 ,此种缓蚀剂所形成的膜层很不稳定 ,随着间浸次数的增加 ,膜层破损程度愈甚 ,缓蚀效果减弱 ,缓蚀膜对 90 7A钢表面仅仅是个覆盖层 ,起到抑制了部分阴、阳极反应的作用 ,从而可将缓蚀机制归结为覆盖效应     

碳酸亚铁与碳酸氢亚铁混合物的分析测定方法

<正>碳酸亚铁由于制备工艺的特殊,往往含有碳酸氢亚铁,所以碳酸亚铁的含量一般不以FeCO3来表示,而用Fe~(2+)的含量来表示。纯碳酸亚铁中Fe~(2+)的理论质量分数为48.2%,纯碳酸氢亚铁中Fe~(2+)的理论质量分数仅为31.4%,市售碳酸亚铁的Fe~(2+)质量分数一般在38%~42%之间。因此如何分别测定碳酸亚铁和碳酸氢亚铁的含量至关重要。由于碳酸亚铁中的碳为常量元素,用红外吸收光谱法[1]或国     

咪唑啉缓蚀剂在Fe(001)表面吸附行为的分子动力学模拟

采用分子动力学模拟方法研究了5种不同烷基链长的咪唑啉类缓蚀剂在Fe(001)表面的吸附行为和成膜机制,并对其缓蚀机理进行了深入分析.研究结果表明:咪唑啉分子的极性头基会吸附在金属表面上,而烷基碳链则背离金属表面,并通过自身的扭转形变实现稳定吸附;随着烷基链长的增加,缓蚀剂与金属基体的结合强度逐渐增加,所形成缓蚀剂膜的致密性也逐渐增大;致密的缓蚀剂膜能有效地阻碍腐蚀介质向金属表面扩散,从而达到延缓金属腐蚀的目的.5种缓蚀剂缓蚀性能的理论评价结果与实验结果吻合.     

1-(2-羟乙基)-2-烷基-咪唑啉缓蚀剂缓蚀机理的理论研究

采用量子化学计算、分子动力学模拟和分子力学相结合的方法, 对6种不同烷基链长的1-(2-羟乙基)-2-烷基-咪唑啉缓蚀剂抑制H2S腐蚀的缓蚀机理进行研究, 并对其缓蚀性能进行评价. 前线轨道分布和Fukui指数表明, 6种缓蚀剂分子的反应活性区域均集中在分子的咪唑环上, 3个反应活性中心分别位于咪唑环上的N(4), N(7)和C(8)原子, 可使咪唑环在金属表面形成多中心吸附. 分子的反应活性及活性区域分布对烷基链长并不敏感. 单分子吸附能、膜的内聚能、吸附角和链间距的计算数据显示, 缓蚀剂膜的稳定性以及膜与金属基体的结合强度随链长的增加而增大; 当正构烷基碳链长度大于13时, 缓蚀剂可在金属表面形成一层高覆盖度、致密的疏水膜, 能有效阻碍溶液中的腐蚀介质向金属表面扩散, 从而达到阻碍或延缓腐蚀的目的.     

Investigation of scale inhibition mechanisms based on the effect of scale inhibitor on calcium carbonate crystal forms

To probe the scale inhibition mechanisms,calcium carbonate scale occurring before and after the ad- dition of scale inhibitors was collected.The results from scale SEM confirm that,without scale inhibitor, calcium carbonate scale shows rhombohedron and hexagon,which are the characteristic feathers of calcite.After addition of inhibitors,morphology of scale is changed,and the more efficient the scale inhibitor is,the more greatly the morphology is modified.To elucidate the scale constitute,they were further analyzed by FT-IR,XRD.Besides calcite,vaterite and aragonite occur in calcium carbonate scale after addition of inhibitors,and the higher scale inhibition efficiency is,the more vaterite presents in scale.It can be concluded that the alteration of morphology is ascribed to the change of crystal form. There are three stages in the crystallizing process including occurrence and disappearing of unstable phase,occurrence and disappearing of metastable phase,development of stable phase.Without scale inhibitors,metastable phases usually transform into stable phase,thus the main constitute of formed scale is calcite.When scale inhibitors are added,both formation and transformation of metastable phases are inhibited,which results in the occurrence of aragonite and vaterite.From the fact that more vaterite presents in scale with a more efficient scale inhibitor added,we can see that the function of scale inhibitor is realized mainly by controlling the crystallizing process at the second stage.     

EIS studies of the destruction behavior of a corrosion inhibitor film on carbon steel surface under hydrodynamic conditions

Effect of surface water shear stress on the performance of an inhibitor film used in the carbon steel pipelines for oil and gas product transportation is studied. Experiments were conducted in laboratory by electrochemical impedance spectroscopy (EIS). EIS that was carried out under various rotation rates, different temperature, and immersion time was taken to investigate the behavior of a corrosion inhibitor and the destruction process. Typical EIS spectral changes were acquired during the film destruction processes, and this means that EIS is an effective method for evaluating inhibitor performance and monitoring the film layers’ behavior. Experimental results show that the film layers become more porous with increase in rotation rates and temperature. Therefore, the performance of this corrosion inhibitor decreased resulting from surface shear stress and bubble impact. In addition, scanning electron microscopy (SEM) was also taken to help confirm the inhibitor film structure under different conditions.     

CO<Subscript>2</Subscript> corrosion inhibition by hydroxyethyl,aminoethyl, and amidoethyl imidazolines in water–oil mixtures

The corrosion behavior of hydroxyethyl, amino ethyl and amid ethyl imidazolines corrosion inhibitors was evaluated by using potenthiodynamic polarization curves, linear polarization resistance, and electrochemical impedance spectroscopy techniques. Solutions included deaerated 3% NaCl, 3% NaCl+diesel saturated with CO₂ at 50 °C with and without inhibitors. Regardless of the presence of diesel, the corrosion rate was decreased with the addition of the inhibitors, but the time to reach a steady state was longer than when the oily part, i.e., diesel, was present. In the absence of the oily part, the impedance results showed that the film formed was porous, allowing the electrolyte to diffuse through it and corrode the metal. When the oily part was present, the film formed was much more stable, not porous, and did not allow the electrolyte to corrode the sample. The most efficient inhibitor was the amid ethyl imidazoline, whereas the least efficient was the hydroxyethyl imidazoline, because the film formed by the former was much more stable from the beginning of the test.     

溶液电导率法对碳酸钙结晶动力学的研究

溶液电导率法对碳酸钙结晶动力学的研究;结垢;电导率     

模拟混凝土孔隙液中D-葡萄糖酸钠复合缓蚀剂对钢筋的阻锈作用

应用电化学技术, 结合扫描电子显微镜(SEM)观测, 研究D-葡萄糖酸钠、钼酸钠和硫脲三组分复合缓蚀剂对模拟混凝土孔隙液中钢筋腐蚀行为的影响及其阻锈作用. 结果表明: 在含3.5% (w) NaCl的模拟混凝土孔隙液中, 复合缓蚀剂具有协同效应, 对钢筋有良好的阻锈作用. 当D-葡萄糖酸钠、钼酸钠和硫脲浓度分别为750、250和500 mg·L^-1时, 对钢筋的缓蚀效率可达到94.5%. 应用软硬酸碱(HSAB)理论分析缓蚀机理, 可认为三组分复合缓蚀剂在钢筋表面共同形成保护膜而阻止钢筋的腐蚀.     

分子结构对咪唑啉缓蚀剂膜在Q235钢表面生长和衰减规律的影响

采用弱极化法、电化学阻抗谱等手段研究了烷基咪唑啉和硫脲基烷基咪唑啉缓蚀剂对Q235钢在饱和CO2盐溶液中的缓蚀行为变化, 探讨了吸附膜的形成与衰减规律. 结果表明, 烷基咪唑啉和硫脲基烷基咪唑啉缓蚀剂都是以控制阳极过程为主的混合界面型缓蚀剂. 在85 ℃下, 烷基咪唑啉成膜相对较慢, 吸附能力较弱, 容易发生脱附; 而硫脲基的引入, 使得硫脲基烷基咪唑啉缓蚀剂溶液存在自动修复能力, 增强了咪唑啉环的吸附性能, 提高了缓蚀剂的缓蚀性能; 硫脲基烷基咪唑啉水解开环后, 成膜性能下降, 膜寿命和缓蚀效率也大大降低. 最后采用量子化学计算对上述结论进行了验证和解释.     

缓蚀膜电化学行为与微观粘附力特征

采用传统电化学测试技术及原子力显微镜(AFM)力曲线分析法对十二烷基硫醇/金电极以及十二烷基磺酸钠(SDS)/铝电极表面缓蚀吸附膜的吸附行为进行了研究. 结果表明, 随缓蚀剂浓度改变, 电极电化学行为与缓蚀膜的微观粘附力特征呈现出关联性的变化趋势, 表明AFM力曲线技术可成功应用于缓蚀膜吸附行为的研究.     

Study of composites based on polypropylene and calcium carbonate by experimental design

Calcium carbonate is without doubt the most widely used mineral filler. There are good reasons for this popularity, namely the combination of numerous deposits of that material and its suitability for a wide range of applications. In this paper results of rheological analysis based on melt index values of polypropylene composites (PP composites), prepared with different grades of calcium carbonate are reported. The study showed that the experimental design can be used as an important tool to evaluate the effect of CaCO₃ grade and its content in polypropylene (PP). It was observed that the addition of calcium carbonate of different particle sizes and contents provoked a significant change in the rheological behavior of the composites analysed.     

中性介质中铜缓蚀剂的成膜过程

使用光电化学与电化学石英晶体微天平联用（PECQCM）技术对中性介质铜缓蚀剂成膜过程进行了现场研究．结果表明，在中性Na2SO4溶液中钝化型缓蚀剂Na2OrO4对Cu成膜生长有抛物线规律，而由于Cl-的影响，在中性NaCl溶液中，该缓蚀剂膜生长曲线为折线型．沉淀型缓蚀剂Na2SiO3在Na2SO4溶液中的铜晶振电极上不成膜，而在NaCl溶液中可成膜．     

大蒜汁在油田腐蚀介质中的缓蚀作用

本文利用失重法研究了大蒜汁在“碳钢－盐酸”、“碳钢－油田注水”以及分别进行充CO2或H2S“碳钢－油田注水”体系中的缓蚀效果,通过扫描电镜形貌观察和电化学测试初步探讨了缓蚀作用机理。结果发现,大蒜汁在酸性溶液中具有良好的缓蚀效果,在80℃下的15%盐酸溶液中缓蚀效率最高可达95.4%,缓蚀率随着酸浓度的增加而逐渐降低。大蒜汁在三种油田注水中也有一定的缓蚀作用,缓蚀效率在42%到64%之间。采用大蒜缓蚀的金属表面覆盖有一层致密的薄膜,动电位极化测试显示为吸附成膜。