钼酸盐复合缓蚀剂对海水中碳钢的缓蚀作用

采用失重法、极化曲线法和表面分析技术对钼酸盐复合缓蚀剂的缓蚀性能进行了研究,并通过试验确定了与钼酸盐有较好协同缓蚀效应的缓蚀剂配方。结果表明,单一钼酸盐对海水中碳钢的缓蚀率随着钼酸盐浓度的增加而增加,但钼酸盐浓度低于30 mg/L时存在加速碳钢腐蚀的情况。当钼酸盐为40 mg/L、有机膦酸盐(HEDP)为10 mg/L、Zn2 为4 mg/L、葡萄糖酸盐为50 mg/L时,该缓蚀剂对海水中碳钢的缓蚀率超过90%。钼酸盐复合缓蚀剂为阳极型缓蚀剂,海水中添加了缓蚀剂后碳钢试片表面形成了以氧化铁为主要成分,同时含有钼和磷的混合型沉淀膜。

INHIBITION BEHAVIOR OF MOLYBDATE INHIBITORS FOR CARBON STEEL IN SEA WATER

The compound molybdates as corrosion inhibitors of carbon steel in sea water were tested using weight loss,electrochemical polarization and surface analysis techniques.The inhibition efficiency increased with increasing molybdate concentration,but when the single molybdate concentration was lower than 30 mg/L the corrosion of carbon steel would be aggravated.There were synergistic effects between molybdate,organic phosphate(HEDP),Zn2 and sodium gluconate.The inhibition efficiency was over 90% in the proportion of 40 mg/L molybdate,10 mg/L HEDP,4mg/L Zn2 and 50 mg/L sodium gluconate.The compound molybdate inhibitor was an anodic corrosion inhibitor which formed a compact film on carbon steel surface,the main composition of the film was iron oxide with some Mo and P.