碘量法测定含铜物料中铜含量

Determination of Copper Content in Copper-Containing Materials by Iodometry

酸消解是测定铜精矿中铜最为理想的检测方法,常用盐酸和硝酸进行处理,但是对于一些难溶的含铜物料样品,采用酸溶法进行溶解,溶解后期始终有处理不掉的黑色残渣,并且在分析滴定前调酸度后加饱和氟化氢铵会产生黑紫色絮状沉淀,对滴定分析造成严重的影响,使分析结果偏差较大,分析结果不准确。通过酸溶法对含铜物料进行溶解,对不溶物进行过滤分离,分析结果进行回渣补正,对过滤后的滤渣溶解所用氢氟酸的使用量、硝酸的用量等条件进行了实验优化,确立了最终的实验方法,测定结果与实验室外委结果一致,相对标准偏差(RSD)为0.060%~0.16%,用建立的方法测定铜物料中铜含量准确、快速、稳定、可靠,方法适用于含铜物料中铜含量在12.5%~24.5%的检测分析。

Acid digestion is the most ideal detection method for the determination of copper in copper concentrate,which is commonly treated with hydrochloric acid and nitric acid.However,for some insoluble copper-containing material samples,there is always black residue that cannot be treated in the later stage of dissolution,and adding saturated ammonium fluoride after adjusting acidity before titration can produce dark purple flocculent precipitation,which seriously affect the titration analysis,resulting in large deviation and inaccurate analysis results.In this study,copper-containing material wase dissolved by acid dissolution,insoluble materialwas filtered and separated,and the residue was analyzed and corrected.The conditions such as the amount of hydrofluoric acid and the amount of nitric acid used in the dissolution of filtered filter residue were optimized by experiments,and the final experimental method was established.The determination results were consistent with the results of laboratory outsourcing,and the relative standard deviation(RSD) was 0.060%-0.16%,which showed that this method was accurate,rapid,stable and reliable for the determination of copper content in copper materials in the range of 12.5%-24.5%.