Abstract:
A very precise and accurate method for chemical analysis of sintered products (from iron ore fines in "pot grate furnace") is discussed. A matrix modifier/buffer (a mixture of KCl, tartaric acid, HCl and H2SO4) is used to prevent interference of iron in the determination of calcium and magnesium by flame atomic absorption spectrometry. Also, an EDTA titration method is recommended for calcium and magnesium after separating iron in the form of mixed oxides by ammonia-ammonium chloride buffer. Statistical data for a series of experiments are presented and precision values are found to be comparable with those of conventional methods used for complex met allurgical products. For the majority of cases, the agreement between the two methods is extremely good. A slight deviation has been noted in a few samples which may be overcome by a more thorough sampling prior to analysis.