新型高温酸化缓蚀剂SJ-1的制备及性能研究

Preparation and Properties of a New High Temperature Acidified Corrosion Inhibitor

为进一步增强酸化缓蚀剂在高温深井中的缓蚀效果,以氯甲基萘为季铵化中间体,与双曼尼希碱反应,合成得到一种双曼尼希碱季铵盐,通过单因素分析法优选复配分散剂和增效剂得到高温酸化缓蚀剂SJ-1,使用失重法和电化学法评价其缓蚀性能。研究结果表明,高温酸化缓蚀剂SJ-1在180℃下,加量仅为3%时,就能使N80钢片在20%盐酸和土酸中的腐蚀速率分别达到70.15 g/(m^(2)·h)和65.32 g/(m^(2)·h),均小于SY/T 5405—2019中的一级指标;高温酸化缓蚀剂SJ-1是以抑制阳极过程为主的混合控制型缓蚀剂;量子化学计算结果表明,以氯甲基萘为中间体合成的双曼尼希碱季铵盐缓蚀性能优于以氯化苄为中间体合成的。

In order to further enhance the corrosion inhibition effect of acidification inhibitor in high-temperature deep wells,a double Mannich base quaternary ammonium salt was synthesized by using chloromethylnaphthalene as quaternary ammonium intermediate and reacting with double Mannich base.The compound dispersant and synergist were optimized by single factor analysis to obtain high-temperature acidification inhibitor SJ-1.The corrosion inhibition performance was evaluated by weight loss method and electrochemical method.The results show that the corrosion rate of N80 steel sheet in 20%hydrochloric acid and earth acid can reach 70.15 g/(m^(2)·h)and 65.32 g/(m^(2)·h),respectively,when the dosage of high-temperature acidification inhibitor SJ-1 is only 3%,which are less than the first-class index in SY/T5405—2019.High temperature acidification inhibitor SJ-1 is a mixed control inhibitor which can inhibit both cathode reaction and anode reaction.