咪唑啉季铵盐缓蚀剂的制备及其性能研究

采用苯甲酸、三乙烯四胺为原料合成咪唑啉母体,用1-氯-3-苯基丙烷对其进行改性来制备咪唑啉季铵盐缓蚀剂。针对国内某含CO2油田的开发状况,动态失重法研究了咪唑啉季铵盐在6MPa下模拟油田水介质中对L80钢在不同缓蚀剂浓度、不同温度和不同时间下的缓蚀性能。结果表明:在试验条件下,随着温度的升高,缓蚀效率有明显的下降,到90℃时变化趋于平缓;在腐蚀反应初期,腐蚀速率很高,但随着腐蚀时间的延长,腐蚀速率明显下降,在较长的一段时间之后,缓蚀效率就几乎不再下降,而是稳定在一个较小的范围之内,所合成的缓蚀剂达到了预期的结果。     

长链烷基咪唑作用下铝箔的腐蚀行为

研究了长链烷基咪唑缓蚀剂在铝箔腐蚀中的作用。结果表明,温度、盐酸浓度和长链烷基咪唑浓度对铝箔腐蚀有重要的影响。随盐酸浓度加大,腐蚀速率逐步加大;发现离子液体浓度较小时,缓蚀效率变化明显。高温时长链烷基咪唑仍呈现出良好的缓蚀性能。对腐蚀作用机制进行了初步探讨。     

咪唑啉基双季(镂)-季铵盐型缓蚀杀菌剂的合成与性能研究

以1,3-二溴丙烷、三苯基膦和十六烷基氨乙基咪唑啉为原料,合成了一种新型的咪唑啉基双季(锛)-季铵盐型缓蚀杀菌剂,并对产物的结构进行了表征.采用平皿计数法测定产物的杀菌性能,结果表明:在药剂用量为3mg/L时,大肠杆菌杀菌率达95％以上;并且通过旋转挂片腐蚀实验方法,对产物的缓蚀性能进行测定,研究了介质温度、缓蚀剂浓度以及腐蚀接触时间对缓蚀效率的影响.     

缓蚀剂1,3-二烷基咪唑的合成及其缓蚀性能研究

采用一步法合成了1-丁基-3-甲基咪唑溴盐([BMIM]Br)和1-己基-3-甲基咪唑溴盐([HMIM]Br)等两种烷基咪唑离子液体,并通过电化学阻抗、动电位极化和失重法研究[BMIM]Br和[HMIM]Br对15Mn碳钢在1 mol/L盐酸溶液中的缓蚀行为。研究结果表明:此两种缓蚀剂在1 mol/L盐酸溶液介质中对碳钢都有良好的缓蚀效果,其缓蚀效率都随着缓蚀剂的浓度的升高而增大,在同浓度条件下,缓蚀效率顺序为:[HMIM]Br[BMIM]Br。动电位极化曲线测量表明此两种1,3-二烷基咪唑溴盐的加入对碳钢的阴阳极腐蚀过程都具有抑制作用,[BMIM]Br和[HMIM]Br属于混合型缓蚀剂。同时计算了相关热力学参数如吸附平衡常数(Kads)以及标准吸附自由能(ΔGads)来阐述缓蚀剂的缓蚀机制,热力学计算说明[BMIM]Br和[HMIM]Br在碳钢表面发生了自发的物理吸附。     

复配新型咪唑啉缓蚀剂的性能研究

以咪唑啉和乙二胺为主要原料,复配了一种新型水溶性咪唑啉缓蚀剂A-4,通过静态、动态等实验方法测定咪唑啉缓蚀剂在不同酸介质中、不同添加浓度、不同温度等条件下的缓蚀性能。结果表明,复配的咪唑啉缓蚀剂在加入量为15 mg/L,温度为50℃,pH值为2.52,转速为120 r/min时,对A3钢片具有一定的缓蚀性能,其缓蚀率可达到98.59%。     

系列酸化缓蚀剂型表面活性剂的合成及缓蚀机理的研究

本课题合成了系列咪唑啉树脂缓蚀剂型表面活性剂。研究了它们在盐酸介质中的腐蚀率与温度浓度的关系，并对化合物结构与缓蚀性能及表面活性的关系进行了讨论。     

XS-1型缓蚀剂对2Cr13钢和N80钢缓蚀性能的影响

利用失重法,借助高温高压H_2S/CO_2腐蚀反应釜,研究了XS-1型耐高温新型抗氧缓蚀剂在NaCl介质中的缓蚀性能。通过正交实验法,分析了介质温度、Cl~-浓度、缓蚀剂浓度对2Cr13不锈钢和N80套管钢腐蚀行为的影响。结果表明:Cl~-浓度是影响两种钢腐蚀的主要因素,缓蚀剂浓度的影响力度略小于Cl~-浓度的影响力度。XS-1型缓蚀剂适用于Cl~-浓度高、酸化程度高和温度高的地层液中。     

咪唑啉酰胺在HCl-H_2S腐蚀介质中对低碳钢(A_3)的缓蚀作用

利用极化曲线法和扫描电镜分析对不同浓度水溶性咪唑啉酰胺缓蚀剂在1000mg/L HCl+500mg/L H2S腐蚀介质中对低碳钢(A3)的缓蚀作用进行了研究。结果表明:在HCl-H2S腐蚀介质中,加入浓度为15mg/L时,水溶性咪唑啉酰胺缓蚀剂对低碳钢(A3)具有很好的缓蚀作用。     

在盐酸溶液中[HMIM]BF_4对70高碳钢的缓蚀作用和吸附行为

合成了咪唑类离子液体1-己基-3-甲基咪唑四氟硼酸盐([HMIM]BF_4),采用失重法与电化学方法研究了在1 mol/L HCl溶液中对高碳钢(70钢)的缓蚀性能、吸附行为及缓蚀机理。结果表明,[HMIM]BF_4具有明显的缓蚀作用,属于混合型缓蚀剂,缓蚀效率随着浓度的增加而增大,随着温度升高而下降。该离子液体在碳钢表面的吸附反应为自发放热过程,且该吸附符合Langmuir吸附等温式,属于同时具有物理吸附和化学吸附的混合吸附。     

咪唑啉复配物缓蚀性能的评价

将咪唑啉型缓蚀剂与其它三种物质进行复配得到一种新型缓蚀剂。利用静态失重法测定了采用咪唑啉型缓蚀剂在盐酸介质及乙烯压缩单元混合液中Q235钢的腐蚀速度和相应的缓蚀效率,同时考察了该缓蚀剂的抗乳化性能。结果表明,该咪唑啉型缓蚀剂在盐酸介质中对Q235钢具有较强的缓蚀能力。在pH=4盐酸溶液中,温度是40℃,腐蚀时间为6h及缓蚀剂加入浓度为100μg/g时缓蚀率达到了97．9％,腐蚀速率仅为O．0008mm／a,远低于我国石油天然气行业标准规定的指标,并且该缓蚀剂具有良好的抗乳化性能。     

高浓度氯离子环境中铜合金缓蚀的电化学研究

应用线性电位扫描(LSV)和Tafel实验等电化学测试技术,研究了苯并三氮唑(BTA)浓度、缓蚀剂的复配、温度对铜合金在高浓度氯离子(25%氯化钙溶液)环境中腐蚀行为的影响。结果表明:缓蚀剂浓度改变将引起缓蚀效果的变化,BTA浓度较低时,铜合金腐蚀电位随缓蚀剂浓度增大而升高,腐蚀速率降低;BTA浓度超过0.2%后,铜合金腐蚀电位和腐蚀速率趋于稳定;NaNO2、Na2MoO4、(NH4)2MoO4等缓蚀剂与BTA复配,对改善缓蚀效果有一定作用;温度对缓蚀效果有重要影响,铜合金在高浓度氯离子溶液中的腐蚀速率随温度的升高而加快,缓蚀剂的缓蚀效果随温度的升高而降低。     

土酸溶液中苯扎氯铵对不锈钢的缓蚀作用及吸附热力学研究

为了研究土酸介质中烷基季铵盐类阳离子表面活性剂对不锈钢的缓蚀及吸附作用,采用静态失重法在不同温度的10%土酸溶液中苯扎氯铵对304#不锈钢的缓蚀作用,应用吸附理论和Sek ine方法对静态挂片试验数据进行处理。结果表明,苯扎氯铵在不锈钢表面的定向吸附是产生缓蚀的主要原因,当其含量达到一定浓度后,缓蚀作用基本保持不变;在浓度为0~0.2%时,其在不锈钢表面的吸附服从Langmu ir吸附等温式,相关系数大于0.99;缓蚀率随浓度的增加和温度的升高而增大,是由吸附过程中表现为总熵增加的特点决定的;获得了吸附过程ΔHo、ΔSo和ΔGo等重要热力学参数。     

Classic and local analysis of corrosion behaviour of graphite and stainless steels in polluted phosphoric acid

In phosphoric acid solution (40% H₃PO₄), the corrosion behaviour of graphite and stainless steels was studied by the use of different electrochemical methods, namely polarization curve analysis, electrochemical impedance spectroscopy (EIS) and scanning vibrating electrode technique (SVET). The combined effect of chemical impurities and the increase of medium temperature was studied to approach the real conditions in the process of phosphoric acid manufacturing. It was found that the current density measured by polarization curves increased with the presence of chloride and sulphate ions in the acid solution whatever the tested material. Compared to stainless steels, graphite had the best corrosion resistance in polluted phosphoric acid. However, for graphite the increase of temperature from 20 to 80 °C induced an increase of the corrosion rate and potential and a decrease of the resistance confirmed by EIS results. Subsequently, local currents were detected at the surface of the sample by using the scanning vibrating electrode technique. From the data obtained, graphite surface manifested a distinctive behaviour from that of stainless steels. A generalized corrosion was occurred on graphite whereas a localized corrosion was observed for stainless steels. These results show a clear interest of graphite as component material in some of the equipments of the phosphoric acid industry.     

烯丙基硫脲对金属材料在盐酸中的缓蚀性能研究

文章通过静态失重法和电化学法对缓蚀剂烯丙基硫脲在盐酸体系中对金属材料的缓蚀性能进行了研究。分别考察了不同缓蚀剂浓度、挂片温度及不同金属材料等情况下烯丙基硫脲的缓蚀性能。结果表明,烯丙基硫脲对Q235碳钢的缓蚀性能较好,失重法实验结果表明,在20℃下,0.5 mol/L盐酸溶液中加入100 ppm烯丙基硫脲对不锈钢的缓蚀率可达93%;0.5 mol/L盐酸溶液中加入50 ppm烯丙基硫脲对Q235碳钢的缓蚀率可达94%。电化学法实验结果则表明,当烯丙基硫脲浓度达到1000 ppm时,对不锈钢的缓蚀率达到97%,对Q235碳钢的缓蚀率可达98%。     

Thiazoles as corrosion inhibitors for mild steel in formic and acetic acid solutions

2-(N,N-dimethylamino) benzylidene imino-4-(4-methyl phenyl)-1,3-thiazole (DIMPT), 2-benzylidene imino-4-(4-methyl phenyl)-1,3-thiazole (BIMPT), 2-salicylidene imino-4-(4-methyl phenyl)-1,3-thiazole (SIMPT) and 2-cinnamylidene imino-4-(4-methyl phenyl)-1,3-thiazole (CIMPT) were synthesized in the laboratory and their influence on the inhibition of corrosion of mild steel in 20 formic acid and 20 acetic acid was investigated by weight loss and potentiodynamic polarization techniques. The inhibition efficiency of these compounds was found to vary with their nature and concentration, temperature, immersion time and acid concentration. The values of activation energy and free energy of adsorption of the thiazoles were calculated to investigate the mechanism of corrosion inhibition. The adsorption of all the thiazoles on mild steel surface was found to obey Langmuir adsorption isotherm. The potentiodynamic polarization result revealed that the compounds studied are mixed type inhibitors. Electrochemical impedance spectroscopy was used to investigate the mechanism of corrosion inhibition.     

热处理与加工成型工艺对双相不锈钢流动腐蚀的影响

研究了热处理与加工成型工艺对双相不锈钢在流动 3 .5 %NaCl溶液中流动腐蚀的影响。结果表明 ,随着固溶处理温度Ts 的升高 ,锻压双相不锈钢的耐蚀性降低 ;随着时效强化时间的延长 ,锻压双相不锈钢的硬度增大 ,耐蚀性有所提高 ,但是锻压双相不锈钢的耐流动腐蚀性能与它的硬度并不存在一致对应的关系。铸造双相不锈钢在流动 3 .5 %NaCl溶液中的腐蚀速度随着介质流速的增大而缓慢上升 ,高流速条件下 ,其表面发生了严重的坑、点等局部腐蚀。固体颗粒的加入 ,促使其流动腐蚀加剧 ,且存在一个使腐蚀速度急剧上升的临界流速值 ,其流动腐蚀过程主要受阳极过程控制     

Cr23Mo1N奥氏体不锈钢的耐点蚀性能研究

通过Mott-Schottky曲线、动电位极化、循环极化以及电化学阻抗谱等方法研究了温度对Cr23Mo1N奥氏体不锈钢(HNSS)在3.5%Na Cl溶液中耐点蚀性能的影响。结果表明:随着温度的不断升高,高氮钢的自腐蚀电位和点蚀电位呈下降趋势,腐蚀电流密度逐渐增大,钝化膜阻抗降低,高氮钢钝化膜的半导体性质在不同温度下发生改变,高氮钢随温度的升高点蚀敏感性增大,已发生点蚀的试样不能自修复。并与普通316L不锈钢进行对比,高氮钢表现出更加优越的耐蚀性。     

Inhibition of steel corrosion by potentiodynamic deposition of poly(N-methyl carbazole)

Poly(N-methyl carbazole) (PNMeCz) coating was deposited on 304 type stainless steel (SS) by electropolymerization of N-methyl carbazole monomer in tetrabutylammonium perchlorate containing acetonitrile solution using cyclic voltammetry. PNMeCz coating was characterized by attenuated total reflectance-Fourier transform infrared spectroscopy, scanning electron microscopy, thickness, conductivity, and contact angle measurements. Corrosion performance of the polymer-coated steel electrodes was investigated in 1 M H₂SO₄ solution using open circuit potential–time (E_ocp–t) curves, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques. PNMeCz coating was found to provide anodic protection to the substrate and significantly reduce the corrosion rate of SS in acidic medium.     

Investigations of the passive layer cracking by means of Dynamic Electrochemical Impedance Spectroscopy

The Dynamic Electrochemical Impedance Spectroscopy has been applied for stress corrosion cracking (SCC) investigations. The effect of applied potential and tensile stresses on the stress corrosion cracking behaviour of type 304L stainless steel (SS) immersed in 0.5 M NaCl solution of room temperature has been examined. This paper presents impedance spectra obtained for 304L stainless steel samples at the different potential values. The results obtained proved the possibility of providing new details about the dynamics of the initiation and propagation of the crack path compared to classical electrochemical techniques.     

CD-4MCu双相不锈钢在稀硫酸介质中的腐蚀磨损行为

用失重法测定了固溶处理态和固溶+时效处理态CD-4MCu双相不锈钢在稀硫酸介质中的腐蚀磨损速率。结果表明,CD-4MCu在固溶态时硬度低,耐腐蚀磨损性能差;在固溶+时效处理态时硬度高,耐腐蚀磨损性能好。介质温度和浓度升高,CD-4MCu双相不锈钢腐蚀及磨蚀增加,腐蚀磨损交互作用增大。