沉淀分离-EDTA返滴定法测定卡尔多炉渣中的铅量

Determination of Lead Content in Kaldor Slag by EDTA Back Titration with Precipitation Separation

采用沉淀分离-EDTA返滴定法建立了卡尔多炉渣中铅含量的测定方法,探讨了样品中共存元素干扰及操作细节等因素对分析结果的影响。实验表明,氟化氢铵用量0.10g、硫酸洗涤次数5～6次、陈化时间3h、氨水加入量5mL、乙酸乙酸钠缓冲溶液加入量30mL、微沸时间15～20min时,方法的加标回收率99.8%～100%,两个实际样品测定结果的相对标准偏差(RSD,n=8,分别为0.14%和0.15%。方法准确度高,精密度好。

This paper adopts EDTA back titration precipitation separation method to establish the detection method of lead content in Kaldor slag,discusses the influence of interference of coexisting elements and details of the operation and other factors of samples to the test results.The experiments shows,0.10 g ammonium hydrogen fluoride,sulfuric acid washing 5-6 times,aging time 3 h,add 5 mL ammonia and 30 mL acetic acid sodium acetate buffer solution,then 15-20 min boiling time,the recovery ranged is from 99.8%to 100%,the RSD(n=8)of two actual samples measured resultsare 0.14%and 0.15%.The method has high accuracy and precision.