盐类浓度对油酸咪唑啉季铵盐缓蚀率的影响

针对油田污水富含钙、镁、钠等盐类的现状,合成了油酸咪唑啉季铵盐,采用电化学极化法和静态失重法测试了其缓蚀性能,并采用电化学极化法考察了强酸腐蚀介质中氯化钙、氯化镁及氯化钠3种盐的浓度对该缓蚀剂缓蚀率的影响。结果表明:该缓蚀剂是一种以阳极抑制为主的混合型缓蚀剂;在1mol·L-1 HCl溶液中,当缓蚀剂浓度为5mg·L-1时,N80钢片的腐蚀速率和缓蚀剂的缓蚀率趋于稳定;随着介质中盐类浓度的增大,缓蚀剂的缓蚀率逐渐减小。分析认为,缓蚀率减小的原因可能是由于介质的电导率增大,导致腐蚀速率加快。

Effect of Salt Concentration on the Corrosion Inhibition Rate of Oleic Acid Imidazoline Quaternary Ammonium Salt

Imidazoline derivatives are widely used in oil fields as a type of corrosion inhibitor.In view of the current situation of oilfield wastewater abundant in calcium,magnesium,sodium and other salts,oleic acid imidazoline quaternary ammonium salt was synthesized,and its corrosin inhibition behavior was determined by electrochemical polarization method and satatic weight-loss method.In 1 mol · L-1 HCl solutions containing three salts,i.e.,CaCl2,MgCl2 and NaCl,the effect of salt concentration on the corrosion inhibition rate of the imidazoline corrosion inhibitor was investigated by using electrochemical polarization method.The results showed that,the corrosion rate of steel N80 and the corrosion inhibition rate of the corrosion inhibitor were stable in 1 mol · L-1HCl solution while concentration of the corrosion inhibitor reached 5 mg · L-1 ; with the increase of salt concentration in the corrosion medium,the corrosion inhibition rate gradually decreased.It was analyzed that the decrease of corrosion rate was probably due to the conductivity increment of the corrosion medium,which speeded up the corrosion rate.