【作者】 蒋华鹏；

【导师】 石顺存；

【作者基本信息】 湖南科技大学 ， 应用化学， 2007， 硕士

【摘要】 环烷酸是石油化工的副产品,在我国产量达3万吨/a以上。但资源利用率低,开发潜力很大。对环烷酸咪唑啉两性化物作为缓蚀剂进行研究具有重大的意义。本论文以环烷酸和二乙烯三胺为原料合成的一种油溶性环烷基咪唑啉中间体分别与氯乙酸钠和丙烯酸进一步合成为两性咪唑啉,对二种不同的合成,考察了不同的反应条件对合成产物的影响,确定了适宜的合成条件如下:咪唑啉与氯乙酸钠反应的适宜条件是:咪唑啉与氯乙酸钠的摩尔比为1:4;反应温度80℃-90℃;pH8-10;反应时间与固含量相关为4h-13h。咪唑啉与丙烯酸反应的适宜条件是:咪唑啉:丙烯酸（摩尔比）=1:4;反应温度:110℃-140℃;反应2h;最后加入与丙烯酸等摩尔的NaOH溶液。初步对比了二种产物的缓蚀性能,选取乙酸基两性咪唑啉MC为代表,运用失重法研究了它在不同腐蚀条件下的缓蚀性能如下:在浓缩倍数k=1.5的循环冷却水中采用旋转挂片法得出:单独使用MC20mg/L时对碳钢的缓蚀率为99.5%,腐蚀率为0.0033mm/a,但有轻微点蚀;而转速越高缓蚀率也越高;MC与Zn⁺或HEDP复配,可消除点蚀,碳钢的腐蚀率均低于0.076mm/a。在模拟油田水中采用静态挂片失重法得出:加入50mg/L的MC可使碳钢的缓蚀率达到94.7%,腐蚀率为0.029mm/a,但是有垢下点蚀产生;MC与HEDP复配,用量为100mg/L+20mg/L时无垢产生,缓蚀率为96.2%,碳钢的腐蚀率为0.021mm/a;将模拟油田水中pH调为6,MC用量为60mg/L时无垢产生缓蚀率为99.3%,碳钢的腐蚀率为0.011mm/a。在HCl-H₂S腐蚀液中采用静态挂片失重法得出:在（1000mg/L）HCl-（100mg/L）H₂S溶液中,缓蚀剂MC在80mg/L时达到饱和吸附,缓蚀率达到96.0%,碳钢的腐蚀率为3.3mm/a;用有机胺调节pH到7后可使碳钢的腐蚀率低到0.032mm/a,缓蚀率为99.96%。在100mg/L-500mg/L范围内,随着H₂S浓度的增加,碳钢的腐蚀率上升;加缓蚀剂MC且调pH到7后,当H₂S浓度≤200mg/L时碳钢的腐蚀率可以低于0.125mm/a。更多还原

【Abstract】 Naphthenic acid is produced more than 30000t per year in China as a by-product in petrochemical industry. There are many things for us to do with it for such resource had not been made good use of, and it is very valuable to research naphthenic amphoteric imidazoline as a corrosion inhibitor.In this paper, two kinds of amphoteric imidazolines are synthesised by these reactions: One is imidazoline and sodium monochloroacetate; the other one is imidazoline and acrylic acid. This kind of imidazoline was synthesised by olic acid and diethylenetriamine （DETA）. By the way, several factors that have important effect on the products have been researched, and the optimum reaction conditions have been obtained as follows:The optimum conditions of the reaction between imidazoline and sodium chloroacetic are: Reactants’s molar ratio is n（imidazoline）: n（sodium chloroacetic）=1:4; Reaction temperature is 80℃-90℃; pH8-10; reaction time is about 4h-13h,which is due to the ratio of reactant to water.The optimum conditions of the reaction between imidazoline and actylic acid are: Reactants’s molar ratio is n（imidazoline）: n（actylic acid）=l:4; Reaction temperature is 110℃-140℃; Reaction time is about 2h. Aqua NaOH was added as the same molar as actylic acid in the end.Amphoteric imidazoline acetic （MC） has a better inhibition efficiency than the other one in a senior corrsion test and its anticorrosion ability has been tested by weight loss method, and the results are as follows:Rotary coupon corrosion test is used in circulating cooling water, whose condensing multiple k=1.5. The corrosion inhibition efficiency is 99.5%, and the corrosion rate of carbon iron is 0.0033 mm/a when the concentration of MC is 20mg/L. The faster the water is running, the higher the corrosidon inhibition efficiency is. MC cooperated with Zn⁺ or with HEDP can keep dot corrosion away and can make the corrosion rates below 0.076mm/a. Weight loss method is carried out in simulated oilfield water. The anticorrosion efficiency is 94.7% and corrosion rate is 0.029mm/a when adding MC of 50mg/L, but it could not keep away dot corrosion because of scale. Adding 100mg/L MC and 20mg/L HEDP can inhibit scale completely, and the corrosion inhibition efficiency is 96.2%,the corrosion rate is 0.021mm/a; Using H₂SO₄ or other acid to keep the water’s pH at 6 and adding MC of 60mg/L can inhibit scale completely, and the corrosion inhibition efficiency is 99.3%,the corrosion rate is 0.011mm/a.Weight loss method is carried out in HCl-H₂S water. In such corrosive water of （1000mg/L） HCl-（100mg/L） H₂S, adding MC of no less than 80 mg/L, the corrosion inhibition efficiency is 96.0%, and the corrosion rate is 3.3mm/a, for when MC reaches full adsorption on iron surface. Adding MC and using organic amine to keep the corrosive water’s pH at 7 can low down the corrosion rate to 0.032mm/a, and get the anticorrosion efficency of 99.96%. The corrosion rate of iron increases as the H₂S’s concentration increasing in the rang of 100mg/L-500mg/L. Adding MC can lower the corrosion rate of iron less than 0.125mm/a if H₂S’s concentration is no more than 200mg/L.更多还原