A. SARWAR ET AL.
824
4. Conclusion
Thar coal has been ranked as lignite. SiO2 and Al2O3 were
identified as the major and Fe2O3 and CaO as the minor
metal oxides in the ash residue. The surface of coal has
been characterized by macro, meso and micropores with
the irregular aggregates of minerals of calcium, sodium,
potassium and aluminum. pzc of Thar coal ranges from
pH 6.00 - 6.27. At this pH fines of coal float relatively
easily, so the coal washing of low-rank coal of hydrophilic
nature may work fast.
5. Acknowledgements
The authors are grateful to Dean of Science, University
of Karachi, for the financial support.
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