全自动电位滴定法测定元明粉中钙镁合量的研究

Automatic Potentiotitrimetric Determination of Total Amount of Ca-Mg in Sodium Sulfate

本论文采用全自动电位滴定仪，在pH10的氨一氯化铵缓冲溶液中，选择EDTA—Hg指示剂以及EDTA滴定剂。测定元明粉中钙镁合量。结果显示：在试验条件下，利用镁离子测定试验的RSD为0．43—1．64％，加标回收率为98．25—107．50％。该法操作简单，能准确地测定元明粉中的钙镁合量。

The total content of Ca-Mg in sodium sulfate was determined by automatic potentiotitrimetric titration using EDTA-Hg as indi- cator and EDTA standard solution as titrant in an ammonical buffer solution of pH 10. The proposed method was applied to the determination of Ca-Mg in sodium sulfate,giving values of recovery and RSD in the ranges of 98.25-107.50% and 0.43-1.64% for Mg.