Historical development of methods for the analysis of mineral raw and secondary materials

In a chemical laboratory a wide range of different mineral raw and residual materials with partly extremely different matrixes must be analysed. Initially, at least seven operations were needed to be able to analyse the main components of a raw material or secondary material sample. Iron titration, for a very long time being the most exact technique for Fe analyses, could be successfully changed from the use of toxic mercury to direct TiCl3-based titration. For more than 20 years, the main elements in the burden (SiO2, Al2O3, CaO, MgO, Na2O, K2O) were measured based on atomic absorption after disintegration of the melt. The measurement of P and S required additional analyses. Due to the purchase of an inductively coupled plasma source (ICP) and slight modification to the process of melt disintegration, it has been possible for about two years now to measure these elements simultaneously. The plausibility analysis carried out after each complete analysis, e.g. for iron ores (12 elements + FeO and annealing loss), provides values in the range of 99.9-100.1%, proving the preciseness of the analytical work. If certain analysis values do not match the test series, this is mostly due to errors during sampling or sample separation.