【作者】 赵萃红；

【导师】 赵景茂；

【作者基本信息】 北京化工大学 ， 材料科学与工程， 2011， 硕士

【摘要】 硫化氢和二氧化碳在油气田的开采和集输系统中对钻井用具和输气管道产生严重的腐蚀,造成局部壁厚减薄或穿孔,甚至导致氢脆和突发性的应力腐蚀开裂,容易引起事故,造成重大的经济损失和人员伤亡,采取防腐措施势在必行,采用缓蚀剂可以有效地减缓腐蚀,油溶性缓蚀剂由于能更好地吸附于金属表面,且吸附时间相对较长,因此比水溶性缓蚀剂表现出更好的缓蚀性能。本文对合成咪唑啉缓蚀剂的有机酸和有机胺进行了系统的筛选,用碳链长度6-18的饱和脂肪酸合成了七种咪唑啉缓蚀剂,用静态失重和电化学方法研究了有机酸碳链长度对咪唑啉缓蚀性能的影响,表明当碳链长度为10时油溶性和缓蚀效果较好。通过比较合成过程中不同催化剂和脱水剂对缓蚀剂缓蚀性能的影响,得出活性氧化铝催化时缓蚀效果最好。另外在合成并评价了一系列工业脂肪酸咪唑啉后,通过静态失重法筛选出了几种缓蚀效果较好的咪唑啉缓蚀剂。采用动态高压釜失重试验评价了筛选出的几种缓蚀剂,并不断改进合成工艺,采用端基改性的方法合成出了一系列1#酸咪唑啉衍生物。比较1#4420120和1#4420180的缓蚀效果可知,在180℃时合成的衍生物缓蚀率高于120℃时的。经过一系列的评价比较,发现0924为缓蚀效果最好的一种,经缓蚀剂预膜后的试片在压力为3.6MPa,转速为600r/min,温度为60℃的高压釜环境中腐蚀速率仅为0.0025mm/a,它的缓蚀效果优于国外缓蚀剂CI545和ME805。秉着“腐蚀速率小且点蚀少”的原则,将油溶性缓蚀剂和水溶性缓蚀剂如喹啉、咪唑啉季铵盐以及表面活性剂等进行了复配,动态高压釜试验证明OP-15能有效地减少点蚀的发生。采用红外光谱谱表征了合成的缓蚀剂,谱图中有咪唑啉的特征吸收峰,同时有酰胺的特征吸收峰,说明合成的产品是咪唑啉和酰胺的混合物,采用动电位极化扫描研究了咪唑啉缓蚀剂的缓蚀机理,极化曲线的特征表明,咪唑啉缓蚀剂极大地减小了腐蚀电流密度,并使自腐蚀电位向更正的方向移动,阳极区地极化曲线特征发生了明显的变化,说明咪唑啉是一种阳极型缓蚀剂。用交流阻抗研究了缓蚀剂膜寿命,同等条件下0924缓蚀剂膜的寿命达到7天。更多还原

【Abstract】 Hydrogen sulfide and carbon dioxide result in serious corrosion to the drilling equipment and gas pipelines. They always make the pipelines thinner or perforated, and even lead to hydrogen embrittlement and stress corrosion cracking, which easily cause severe accidents, economic losses and even injury and death. So it is imperative to take some measures to slow down or prevent corrosion.The using of corrosion inhibitors can effectively inhibite the corrosions. Oil-soluble corrosion inhibitors have better performance than the water-soluble corrosion inhibitors due to their better and longer adsorption on the metal surface.In this paper, seven imidazolines were synthesized by different saturated fatty acids with 6 to 18 carbon chain and diethylenetriamine. The relationships between fatty acid carbon chain length and inhibitive performance of imidazolines were studied by static weight loss test and electrochemical methods. The results showed that it had a better oil-soluble and inhibitive perfoemance when the carbon chain length of corrosion was 10. Activative alumina was proved to be the best catalysts after comparing the inhibitive perfoemance of oleic imidazolines synthesized by using different catalysts and dehydrating agent. After evaluating a series of industrial fatty acid imidazoline through the static weight loss test, several good imidazoline corrosion inhibitors such as D2,1# IM180,1# 4420180,0924,0131 etc. were selected and evaluated in dynamic autoclave.A series of 1# acid imidazoline derivatives were synthesized by modifying end-groups. Comparing inhibitive performance of 1# 4420180 and 1# 4420120 showed that derivative synthesized at 180℃was better than it at 120℃. After several evaluation comparasion, the 0924 was suggested to be the best inhibitor under the autoclave test environment at 3.6MPa,600r/min, and 60℃. Its corrosion inhibitive perfoemance was better than foreign corrosion inhibitors CI-545 and ME-805 as its corrosive rate was only 0.0025mm/a. Adhering to the principle of "lower corrosion rate and less pitting ", oil-soluble corrosion inhibitors were compounded with water-soluble corrosion inhibitor such as quinoline, imidazoline quaternary ammonium salts and surface active agent. It was proved OP-15 can effectively reduce the occurrence of pitting in dynamic autoclave test.Characterized by IR spectral indicated that the synthesis product was a mixture of imidazoline and amide. The polarization curves show that the imidazolines greatly reduces the corrosion current density, and made the corrosion potential move to the corrective direction. The anode polarization curves indicated that imidazoline is an anodic inhibitor.更多还原