【摘要】 采用电化学测试技术、化学浸泡方法和现代物理测试技术 ,探讨了高温高浓度溴化锂溶液中碳钢钝化膜的结构及形成机理 .结果表明 ,在 5 5 %LiBr +0 .0 7mol/LLiOH溶液中 (145℃ ) ,随Na2 MoO4 浓度增加碳钢极化阻抗升高 ,析氢量减少 ,当其浓度达到 15 0mg/L以上时对碳钢具有良好的缓蚀效果 ;MoO4 2 -在金属表面还原而参与钝化膜生成 ,在膜的生长过程中吸附于膜的薄弱点形成MoO3,膜中Mo的不同价态形成的电场抑制了碳钢的活性溶解 ;MoO4 2 -还原反应遵循下列反应方程 :MoO4 2 -+2H2 O +2e MoO2 +4OH更多还原

【Abstract】 Adopted by electrochemical measurements, chemical immersion experiments and modern physical examinations, this article discusses the structure of passive state film and its formation mechanism on carbon steel in high temperature and high concentration LiBr solutions. The results show that with increasing the Na 2MoO 4 concentration, the polarization resistance of carbon steel increases and the amount of evolving hydrogen decreases in the 55%LiBr+0.07 mol/L LiOH solution. The results also indicate that Na 2MoO 4 can prevent the corrosion of carbon steel effectively in 55%LiBr+0.07 mol/L LiOH solution when its concentration is greater than 150 mg/L. Moreover, the anodic dissolution procedures are impeded by the electric field owing to different valence of Mo in the film, because MoO 4 2- is reduced first and participates in the film forming process, and then it can be absorbed in the defects of film and develops into MoO 3. The reduction reaction of MoO 4 2- can be expressed by the equation: MoO 4 2- +2H 2O+2eMoO 2+4OH -.更多还原