EDTA络合滴定法测定柱状压块球化剂中金属镁

发布时间：2018-09-05 08:57

【摘要】：随机取柱状压块球化剂不少于20颗约500g,用破碎机快速破碎分散后混合,取其中20g试样,用乙酸(1+9)溶解试样中的金属镁及少量的铁,将大部分铁粉及其他不溶物过滤除去,移取一定体积的滤液,用氨水调节pH值至6~7,经铜试剂沉淀分离铁、铝等干扰离子,三乙醇胺掩蔽剩余干扰离子,以EGTA标准溶液预络合滴定钙,于盐酸羟胺、氨-氯化铵缓冲溶液(pH 10)中,以铬黑T为指示剂,建立了EDTA络合滴定法测定柱状压块球化剂中金属镁含量的方法。使用实验方法对柱状压块球化剂样品进行多次平行测定,相对标准偏差(RSD,n=6)小于2.0%。选取4个柱状压块球化剂样品按实验方法进行测定,并与标准方法JB/T4394-1999和差减法进行比较,测定结果基本一致。实验方法适用于测定金属镁质量分数在5%~15%范围内的柱状压块球化剂。
[Abstract]:At random, not less than 20 nodulizing agents of columnar compaction blocks were taken, and then quickly crushed and dispersed by crusher, and then mixed with 20g sample. Magnesium metal and a small amount of iron were dissolved in the sample with acetic acid (19), and most of the iron powder and other insoluble matter were filtered out. A certain volume of filtrate was removed, the pH value was adjusted to 6 ~ 7 with ammonia, the interference ions such as iron and aluminum were precipitated by copper reagent, the residual interference ions were masked by triethanolamine, calcium was titrated with EGTA standard solution, and the calcium was titrated in hydroxylamine hydrochloride. In ammonia-ammonium chloride buffer solution (pH 10), a EDTA complexometric titration method was established to determine the content of magnesium in the nodulizer of columnar pressed blocks with chrome black T as indicator. The relative standard deviation (RSD,n=6) was less than 2.0 by using the experimental method. Four cylindrical block nodulizer samples were determined by the experimental method and compared with the standard method JB/T4394-1999 and subtractive method. The results were basically consistent. The experimental method is suitable for the determination of the spheroidizing agent of columnar compaction in the range of 5 ~ 15% of magnesium content.
【作者单位】：江苏省沙钢钢铁研究院分析测试中心;
【分类号】：TG115

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