硫酸盐还原菌对Cu在循环冷却水中腐蚀行为的影响

Effect of Sulfate Reducing Bacteria on Corrosion Behavior of Cu in Circulation Cooling Water System

采用电化学测量方法和表面分析技术研究了硫酸盐还原菌对Cu电极在循环冷却水系统中腐蚀行为的影响,并初步探索了L-半胱氨酸对Cu材料的缓蚀效果。结果表明,有菌体系中Cu电极的极化电阻呈现先增大后减小的趋势,且在有菌环境中浸泡第10 d时Cu电极的极化电阻比在无菌环境中的小25.82 kΩ·cm^2。有菌体系中Cu电极的自腐蚀电流密度先减小后增大,与电化学阻抗谱实验呈现相同的趋势。有菌体系中加入不同浓度的L-半胱氨酸后,Cu电极的阻抗弧半径均有所增大,且自腐蚀电流密度均有不同程度的减小,在浓度为10^(-3)mol/L时缓蚀效果最佳。

The microbe induced corrosion of Cu in circulation cooling water system was investigated in the presence of sulfate reducing bacteria by means of electrochemical measurement and surface analysis techniques.Meanwhile,the inhibition effect of cysteine on Cu was also assessed.The results show that,polarization resistance of Cu increased first and then decreased in the water with sulfate reducing bacteria,and the polarization resistance of Cu is 25.82 kΩ·cm^2 lower than that in the sterile water.The corrosion current density of Cu reduced first and then increased,while the electrochemical impedance spectroscopy presented the same tendency.In the sulfate reducing bacteria containing water,the addition of different concentrations of L-cysteine can lead the decline of the corrosion current density Icorrand the expansion of the radius of electrochemical impedance of Cu,particularly with the concentration of 10^-3 mol/L,L-cysteine exhibits the best corrosion inhibition effect for Cu in the water with sulfate reducing bacteria.