催化动力学极谱法测定痕量锰的研究

Study on The Catalytic Kinetic Oscillopolarographic Determination of Trace Manganese

在０．１２６ｍｏｌ／ＬＮＨ３·Ｈ２Ｏ－０．１４４ｍｏｌ／ＬＭＨ４缓冲溶液中（ｐＨ９．４５），Ｍｎ（Ⅱ）能催化过氧化氢氧化酸性铬蓝Ｋ的反应。利用极谱法监测催化反应过程中酸性铬蓝Ｋ的浓度变化，建立了测定痕量锰的催化动力学方法。测定锰的线性范围为０－１．４×１０－３ｍｇ／Ｌ，检出限为８×１０－６ｍｇ／Ｌ。方法已用于测定化学试剂和茶叶中锰，结果满意。

A simple and sensitive catalgtic kinetic Oscillopolarographic method was set up for determination of trace manganese.The slower reaction of acid chrome blue K (ACBK) with H2O2 was catalysed by Mn(Ⅱ)in NH3·H2O-NH4Cl medium(pH 9.45)during heating.The change of ACBK concentiation was traced by a model JP-2 Oscillopolarograph at-0.57V(vs.SCE). The linear ranal of Mn(Ⅱ)and its detection limit are 0 ～1.4×10-3mg/L and 8 ×10-6mg /L respectively.The method can be applied for determination of manganese in some chemical agents and tea.The results are satisfactory.