Pages : 40 – 55
M. Arsala Khan
Various Pakistani coal samples were separated into float and sink fractions using media of different specific gravities. The various float and sink fractions as well as the whole coal samples were ashed at 750°C in a muffle furnace and the ashes were analyzed for Co, Cu, Ni and Zn by atomic absorption spectrophotometer. The results showed that less enrichment of these metals occurred in the sink fraction in media of different specific gravities in case of Makarwal and Sor-Range coals. However, in case of Degari and Shahrigh coals considerable enrichment of these metals occurred in sink fractions. The results were explained by suggesting that in case of Makarwal and Sor-Range coal samples, considerable amounts of these trace metals might occur in close association with the organic structure of coal which are difficult to be removed by the specific gravity method of coal cleaning. In case of Degari and Shahrigh coals, however considerable amounts of these metals might occur as discrete minerals matter which can be separated with ease from coal by the specific gravity method of cleaning.