缓蚀剂阳极脱附现象的研究──Ⅳ．缓蚀剂浓度极值现象

ANODIC DESORPTION OF INHIBITORS Ⅳ.INHIBITOR-CONCENTRATION-DEPENDENT EXTREME BEHAVIOR

使用电化学技术研究了缓蚀剂体系中电化学参数随缓蚀剂浓度的变化。发现在硫酸溶液中；双电层电容、电荷迁移电阻及缓蚀效率均随缓蚀剂浓度变化呈现极值行为。但是，这些参数在盐酸溶液中不存在极值行为。实验结果表明，腐蚀电位和脱附电位均随缓蚀剂浓度增加而正移。但是在硫酸溶液中两者逐渐靠近，甚至重叠，而在盐酸溶液中，两者却逐渐分离。结合极化曲线及阻抗实验结果证实硫酸溶液中电化学参数及缓蚀作用浓度极值现象起因于浓度增加导致缓蚀剂在腐蚀电位附近发生阳极脱附。

In acidic solutions containing propargyl derivative inhibitors,the changes in electrochemical parameters and inhibition performance with inhibitor concentrations were investigated using electrochemical measurements.It was found that in sulfuric acid solution there existed extreme values of double layer the contrary;this kind of extreme phenomenon was not observed in hydrochloric acid medium.By analyzing the changes in desorption potentials and corrosion potentials with inhibitor concentrations,the cause for this extreme phenomenon was demonstrated to be inhibitor desorption occurring around corrosion potential in sulfuric acid solution as the inhibitor concentration reached a certain value.