Determination of magnesium in dolomite

In this work, four methods have been tried in an effort to find the best method for the determination of magnesium in dolomite, The determination of the magnesium content of dolomite, the raw material for the production of cement, is very important in that the quality of cement depends on its magnesium content. The methods are: the Classical titration with hydrochloric acid and sodium hydroxide, the Complexometric titration with EDTA, Atomic Absorption Spectrometry and Absorption Spectrophotoraetry with Brio T and Titan yellow. A statistical analysis was carried out using the Student's t-test at 95% level of confidence and the Correlation coefficient. The Student's t-test showed that there is no significant difference between the results by the methods, except those between the Classical titration and Atomic Absorption -Direct Calibration and Absorption Spectrophotometry - Standard Addition methods. The methods also showed good correlation between them except the classical titration and Absorption Spectrometry - Standard Addition which showed poor correlation(r < 0.90). From the results of the statistical analysis and the difficulties encountered during the course of the analyses it has been decided that Atomic Absorption Spectrometry is the best of the four methods for routine quality control analysis.It has been found that it is more sensitive, has fewer interferences and requires the shortest time. However if the cost of an atomic absorption spectrometer is taken into consideration, the method becomes very expensive. In that case the Complexoraetric titration with EDTA is the next best alternative