钴电解液中微量的锌可用氢氧化钾熔融法分离后以EDTA为试剂用两种不同的电流滴定法进行测定。其中利用EDTA的氧化波的方法,文献上尚未有报导。这一方法也可用来测定与EDTA螯合的其他金属离子如Fe~(+++)、Co~(++)、Ni~(++)、Cd~(++)等。用上法分析一个试样所需时间为40分钟,测定的平均偏差为±2％。 A small amount of zinc in cobalt electrolyte can be separated by potassium hydroxide melting method and then measured by two different current titration methods using EDTA as a reagent. Among them, the method of utilizing the oxidation wave of EDTA has not been reported in the literature. This method can also be used to determine other metal ions chelated to EDTA such as Fe ~ (+++), Co ~ (++), Ni ~ (++), Cd ~ (++) and so on. The time required to analyze a sample using the above method was 40 minutes and the average deviation was measured as ± 2%.