ISO 5418-1:1994

Iron ores — Determination of copper content — Part 1: 2,2′-Biquinolyl spectrophotometric method

The principle of the method specified is decomposition of the test portion by treatment with hydrochloric, nitric and perchloric acids, dehydration of silica, dilution and filtration, ignition of the residue, treatment with hydrofluoric and sulfuric acids, fusion with sodium carbonate, dissolution of the cooled melt in the filtrate, reduction of copper(II) to form the red-violet complex of copper(I), spectrophotometric measurement of the absorbance of the complex at approximately 545 nm. The method is applicable to copper contents between 0,004 % (m/m) and 0,8 % (m/m) in natural iron ores, iron ore concentrates and agglomerates, including sinter products.