Na_2MoO_4-有机膦A复合缓蚀剂对55%LiBr溶液中碳钢的缓蚀行为

Corrosion Inhibition Behavior of Carbon Steel in 55%LiBr Solution Containing Na_2MoO_4-organophosphorus A Complex Inhibitor

采用失重法、电化学测试技术、原子力显微镜和电子探针显微分析等方法考察了Na2MoO4-有机膦A复合缓蚀剂对55%LiBr+0.07 mol/L LiOH溶液中碳钢的缓蚀性能。结果表明,240℃下碳钢在添加800 mg/L Na2MoO4-有机膦A复合缓蚀剂的55%LiBr+0.07 mol/L LiOH溶液中的腐蚀速率为43.2μm·a-1。在沸腾的55%LiBr+0.07 mol/L LiOH溶液中添加该缓蚀剂后,碳钢的钝化电位区间拓宽,钝化电流密度降低,反应电阻Rt值显著增加,缓蚀效率可达94.4%。该缓蚀剂能使碳钢表面形成显微结构为孤岛状的膜层,主要成分为Fe和Mo的氧化物。

The inhibition effect of Na2MoO4-organophosphorus A complex inhibitor on the corrosion of carbon steel in 55%LiBr＋0.07 mol/L LiOH solution was studied by weight-loss tests, electrochemical measurements, AFM and EMPA. The results show that Na2MoO4-organophosphorus A complex inhibitor performed excellent inhibition in the solution. When its concentration reached 800 mg/L in 55%LiBr＋0.07 mol/L LiOH solution at 240 ℃, the corrosion rate of carbon steel decreased to 43.2 μma-1, the anodic passivation region broadened and the passive current density of carbon steel decreased, the inhibition efficiency was 94.4%. At the same time, the charge transfer resistance increased. The compact compound film formed on the surface of carbon steel in 55% LiBr＋0.07 mol/L LiOH solution containing the inhibitor. The film with island structure was mainly composed of iron oxide and molybdenum oxide.