油田酸化液中咪唑啉及其季铵盐的缓蚀作用

Inhibition Performance of Imidazolines and Their Quaternary Ammonium Salts in Acidic Media

采用静态挂片法对合成的两种咪唑啉及其季铵盐的缓蚀性能进行了研究,结果表明,环烷基咪唑啉(NI)、月桂酸咪唑啉(YUC)在60℃15%盐酸、9%的土酸中对N80钢有较好的缓蚀效果;随着咪唑啉季铵盐(NIAS)与硫脲基咪唑啉季铵盐(SUDEI)加量的增大,缓蚀率增大;随盐酸或土酸浓度增加,缓蚀率降低;NIAS的缓蚀效率随温度的升高显著下降,而SUDEI的缓蚀效率受温度影响不显著。NIAS、SUDEI对A3钢的缓蚀效果比对N80钢的缓蚀效果好。在酸性介质中,SUDEI对N80钢的缓蚀效果优于NIAS,在60℃9%土酸中,SUDEI加量为0.1%时,对N80的缓蚀率达到98.50%,腐蚀速率为1.39g/m^2·h,能满足中国石油天然气行业标准要求,而NIAS则不能。

The inhibition performance of two imidazolines and their quaternary ammonium salts was studied by static weight loss method. The results showed that naphthene-base imidazoline（NI）and lauric acid imiclazoline（YUC） had good inhibition efficiency on N80 steel in 15% HCl and 9% mud acid at 60℃. The inhibition efficiency increased with increasing the dosage of naphthene-base imidazoline quaternary ammonium salt（NIAS）and thiourea-base imidazoline quaternary ammonium salt（SUDEI）, and reduced with increasing the concentration of HCl and mud acid. Increasing of temperature decreased remarkably the inhibition efficiency of NIAS, while it had little effect on the inhibition efficiency of SUDEI. NIAS and SUDEI had higher inhibition efficiency on A3 than on N80. SUDEI had higher efficiency of inhibition on N80 steel in acidification medium than NIAS. When the dosage of NIAS was 0. 1 %, the inhibition efficiency on N80 steel in 9% mud acid containing SUDEI at 60℃ was up to 98. 50%, and corrosion rate was 1.39 g/m2 · h, which can meet the demand of China Petroleum and Natural Gas industrial standard, while NIAS can not.