Anodic electrochemical behavior was studied on graphite anode at 1000 ℃ in cryolite-alumina molten salt by means of cyclic voltammetry. The high current peak in a typical cyclic voltammogram was discussed. It is considered that a type of oxyfluoroaliminate complex anions reacts with carbon to form a high-resistance CF film on the anode surface at a high potential. The passivation potential is 3.28 V in 0.5% alumina-containing electrolyte, and the passivation potential increases with alumina content increasing which indicates that the alumina content determines the anodic process in the cryolite-alumina molten salt system.
提出一种简便高效的测定熔盐电导率的新方法——管式电导池法.该方法采用热解氮化硼管自制电导池,以钨丝作为工作电极,石墨作为对电极,采用阻抗仪测定n Na F·Al F3-Al2O3-Ca F2熔盐的电阻,并与Wang经验公式和Choudhary经验公式计算所得电导率数据进行比较.结果表明,自制的管式电导池法所测得数据与经验公式计算得数据相近,并且有较好的准确性和重现性.管式电导池法是一种准确度高、结构简单、造价便宜、能扩大应用范围测定熔盐电导率的有效测试手段.
