碱溶液中添加剂对铝阳极行为的影响

Effect of additives on behavior of aluminum anode in alkaline solution

为了提高铝活化性能以及降低析氢腐蚀,用电化学方法研究了在4 mol/L KOH溶液中,添加剂酒石酸钾钠(C4H4O6KNa)、邻氨基苯酚(NH2C6H4OH)以及复合添加剂对铝阳极(w(Al)=99.999%)电化学行为的影响。结果表明:C4H4O6KNa对抑制铝的析氢腐蚀作用不大,但大幅度提高铝阳极的活性。添加NH2C6H4OH,主要作用是大幅度抑制铝的析氢腐蚀,对铝活性几乎无影响。复合添加剂(C4H4O6KNa+NH2C6H4OH+K2MnO4)能明显降低铝阳极在碱性介质中的极化,提高其活性,同时析氢腐蚀也降低,其最佳配方为:15m mol/L C4H4O6KNa+0.4 mol/LNH2C6H4OH+0.8 mmol/L K2MnO4。

To improve hydrogen evolution rates and activation properties of Al, effects of additives of C4 H4 O6KNa, NH2 C6 H4 OH and their complex on electrochemical behaviors of aluminum anode（99. 999% ）in 4 mol/L KOH solution have been carried out by using electrochemical methods. It has been shown that activation properties of Al are largely improved when C4 H4O6KNa being added into 4 mol/L KOH, but hydrogen evolution corrosion of aluminum is almost hardly inhibited. Furthermore, it has been found that corrosion rate of Al sharply decreases when NH2 C6 H4 OH is added into 4 mol/LKOH, but activation properties of Al don＇t increase. Finally, when optimal formula Of complex additives are. composed of 15 mmol/L C4HO6KNa ＋ 0.4 mol/L NH2C6H4OH ＋ 0.8 mmol/L K2 MnO4, both activation properties and hydrogen evolution corrosion of Al are largely improved.