EDTA络合滴定石灰石中钙镁含量的实验分析

Experimental Analysis of Calcium and Magnesium Content in Limestone by EDTA Compleximetry

工业生产和控制中钙镁测定多采用EDTA络合滴定分析,在实际测定中,发现当p H值大于12.5时,加入糊精、三乙醇胺、氢氧化钾及钙羧酸指示剂,用EDTA络合滴定Ca,以及在p H值为10时,加入盐酸羟胺、三乙醇胺、氨性缓冲溶液及酸性铬兰K-萘酚绿B指示剂,用EDTA络合滴定Mg具有广泛的适用性,实验在p H值大于12.5时,只加入三乙醇胺、氢氧化钾及钙羧酸指示剂,用EDTA络合滴定Ca做了初步的实验分析。

Industrial production and control of calcium and magnesium determination were analyzed most by EDTA compleximetry. In the actual measurement,when p H was more than 12. 5,adding dextrin,triethanolamine,potassium hydroxide and calcium acid indicator complexed with EDTA titration of Ca,as well as PH was 10,adding hydroxylamine hydrochloride,triethanolamine,ammonia buffer solution and acid chrome blue K- naphthol green B indicator,complexometric titration with EDTA Mg,which had broad applicability. Only adding triethanolamine,potassium hydroxide and calcium acid indicator,complexometric titration with EDTA Ca was made a preliminary analysis of the experiment when the PH was greater than 12. 5.