Precision spectrophotometric determination of total iron in chromite ores

Abstract

Chemical and manipulative variables have been examined in detail in order to develop a precise and direct spectrophotometric determination of total iron in chromite ores. Samples are sintered with sodium peroxide in zirconium crucibles (3 h at 510 ± 10 °C), then leached and filtered. The filtrate can be used for the determination of chromium. The residue is dissolved in hydrochloric acid (1 + 1) and iron is determined from the absorbance of the iron(III)-chloro complex at 342 nm. The procedure has been evaluated using standard chrome-iron samples and a series of Sudanese chromite ores. The results are in good agreement and of comparable precision with other data.