EDTA络合滴定法测定钢渣中游离氧化钙

来源期刊：冶金分析2010年第7期

论文作者：龙跃 雷云波 张玉柱 王少宁 韩志杰 师学锋

文章页码：65 - 68

关键词：钢渣； 游离氧化钙； 络合滴定法； EDTA； 乙二醇

Key words：steel slag； free calcium oxide； complexometric titration； EDTA； ethanediol

摘    要：在测定钢渣中游离氧化钙(f-CaO)含量的实验中,选择乙二醇溶液浸取钢渣中游离氧化钙,用EDTA络合滴定法测定其含量。实验中分别考察了乙二醇萃取液用量、萃取温度和恒温振荡时间等对测定结果的影响,并选择已知含量的分析纯氧化钙来修正钢渣中游离氧化钙含量,进而消除溶液稀释及钢渣试样中含有的Fe²⁺、Al³⁺、Mn²⁺等二价金属氧化物相(RO相)对测定结果产生的影响。测定了不同渣系中f-CaO含量,普通钢渣f-CaO含量约为6.95%;气淬渣不同粒径时游离氧化钙含量差异较大:粒径≥2 mm的f-CaO含量为6.82%,粒径为1~2 mm的f-CaO含量为2.63%,粒径为0.6~1 mm和0.15~0.6 mm的f-CaO含量分别为1.85%与1.65%;热焖渣与水淬渣中f-CaO含量低,其值分别为0.55%与0.65%。测定结果的相对标准偏差(RSD)均≤3%,符合测定标准。

Abstract: In the experiment for determining free calcium oxide(f-CaO) in steel slag,the f-CaO was leached with ethanediol solution,and its content was determined by EDTA complexometric titration.The effect of ethanediol dosage,the extraction temperature and the constant temperature oscillating time on determination results were investigated.The analytically pure calcium oxide with known content was used to calibrate the content of f-CaO in steel slag,eliminating the influence of solution dilution and oxide phase(RO) of divalent metal ions such as Fe²⁺,Al³⁺ and Mn²⁺ in steel slag sample.The content of f-CaO in different slags were determined.The content of f-CaO in normal steel slag was about 6.95 %.The content difference of f-CaO in gas quenching slag in different particle sizes was great: 6.82% for ≥2 mm,2.63% for 1-2 mm,1.85% for 0.6-1 mm and 1.65% for 0.15-0.6 mm.The content of f-CaO in hot braised stew slag and water quenching slag were 0.55% and 0.65 %.The relative standard deviations (RSD) of determination results were smaller than or equal to 3%,which met the determination standard.