锌精矿中锌量测定方法的改进

以GB/T 8151.1-2012为基础,通过EDTA滴定法和火焰原子吸收光谱法2种方法的联合,对锌精矿中的锌量测定进行改进。试样采用盐酸、硝酸和硫酸进行分解,在加入氯化铵的条件下,生成锌胺络合物,经过过滤,滤液按照国标方法用EDTA进行滴定,沉淀用原子吸收光谱法进行测定补差,扣除Cd的量,从而测得锌精矿中的最终锌量。改进的测定方法不仅可避免滤液体积难以控制,还可解决未彻底洗净沉淀造成结果偏低等问题。该方法改进了国标方法中须经2次过滤的步骤,既节约了时间,操作上也更为便捷,对锌精矿中锌量测定具有实际的应用价值。

Method improvement on the determination of zinc content in zinc concentrate

Based on GB/T 8151.1-2012, the determination of zinc content in zinc concentrate was improved by EDTA titration combined with flame atomic absorption spectrometry in this paper. The sample was decomposed with hydrochloric acid, nitric acid and sulfuric acid. Upon the addition of ammonium chloride, zinc amine complex was formed and then it was filtered out. The zinc content in the filtrate was titrated by EDTA standard solution and that in zinc amine complex was determined by atomic absorption spectrometry, then they were added up with a deduction of the amount of Cd, thus the zinc content in zinc concentrate was measured. The improved method could not only avoid the difficulty in controlling the volume of the filtrate, but also help solve the problem of lower measurement of zin content caused by incomplete cleaning of zinc amine complex. Time-saving and much more convenient, as this method is, it has practical application value for the determination of zinc content in zinc concentrate.