天然海水中高效缓蚀剂对碳钢缓蚀作用的研究

以锌盐、葡萄糖酸盐为主要缓蚀成分复配的适用于天然海水中碳钢的高效缓蚀剂，用失重法测定其缓蚀效率，并用电化学方法分析其缓蚀作用机理．结果表明：未预膜时缓蚀剂的临界浓度是280mg／L．此时对碳钢的缓蚀率为93．8％，试样表面光亮如初，没有局部腐蚀；预膜后缓蚀剂的临界浓度降为210mg／L，此时对碳钢的缓蚀率为93．1％．通过极化曲线分析可知该缓蚀剂是一种抑制阳极过程为主的混合型缓蚀剂．据交流阻抗谱图分析得到该缓蚀剂成膜反应分3个阶段：反应初期，缓蚀剂在电极表面初步吸附；反应中期，至浸泡48h时第一层缓蚀膜形成；反应后期，缓蚀膜向多层发展．

THE STUDY OF INHIBITIVE MECHANISM OF CORROSION INHIBITORS FOR CARBON STEEL IN NATURAL SEAWATER

The inhibitive effect of compound corrosion inhibitor for carbon steel in natural seawater was studied by weight loss method.The inhibitory mechanism was analyzed by polarization curves and EIS.The results showed that the critical concentration was 280mg/L and the inhibitive efficiency was 93.8% without pre-filming process,and local corrosion was not found; the critical concentration was 210mg/L and the inhibitive efficiency was 93.1% with pre-filming process (1000mg/L,48h).The results of polarization curve indicated that the corrosion inhibitor was mixed-type inhibitor,which mainly inhibits anodic reaction.The results of EIS revealed the reaction of this inhibitor was composed of three stages:corrosion inhibitors were adsorbed on electrode surface primarily during initial stage of reaction,and the first inhibitor film was formed until 48h,while the film developed to multilayers during anaphase stage of reaction.