Abstract

The rates of corrosion of aluminum and hydrogen gas production in sodium hydroxide solutions without and with the additions of chromate, phosphate, and tungstate anions were examined. Potentiometric, weight loss, thermometric, gasometric, galvanostatic polarization, and electrochemical impedance spectroscopy techniques were used. The data show that these anions favored oxide film formation and mitigate hydrogen production. The inhibition efficiency, η, was calculated and found to depend on the anion-type and concentration, as well as, temperature. The inhibition mechanism is assumed to take place through an adsorption process obeying Temkin's isotherm. The thermodynamic parameters for the adsorption process K_ads and ΔG°_ads are calculated and discussed. The surface examination was investigated using SEM and EDX spectroscopy.

摘要

在没有和没有添加铬酸根、磷酸根和钨酸根阴离子的情况下，检查了氢氧化钠溶液中铝和氢气产生的腐蚀速率。使用了电位测定法、重量损失法、温度测定法、气体测定法、恒电流极化法和电化学阻抗谱技术。数据表明，这些阴离子有利于氧化膜的形成并减少氢气的产生。计算抑制效率η并发现它取决于阴离子类型和浓度，以及温度。假设抑制机制通过遵循 Temkin 等温线的吸附过程发生。吸附过程K _ads和 Δ G ° _ads的热力学参数计算和讨论。使用SEM和EDX光谱研究表面检查。