在铁的容量法测定中,近年来已广泛研究应用无汞无毒的分析方法来代替传统的汞盐—重铬酸钾测定法。其中以抗坏血酸作为滴定剂直接测定铁的无毒方法早有报导,唯其缺点是抗坏血酸溶液稳定性较差,常用的硫氰酸盐指示剂的终点变色不够明显,致使 In the determination of iron’s volumetric method, in recent years, there has been extensive research into the application of a mercury-free and non-toxic analytical method to replace the traditional mercury salt-potassium dichromate assay. Ascorbic acid as a titrant for the direct determination of iron non-toxic method has long been reported, the only drawback is the poor stability of ascorbic acid solution, commonly used indicator of thiocyanate end discoloration is not obvious enough, resulting in