Leaching of Minerals in Degari Coal

Mohammad Shakirullah, Imtiaz Ahmad, Mohammad Arsala Khan, Mohammad Ishaq, Habib ur Rehman, Uzma Khan

Department of Chemistry, University of Peshawar, N.W.F.P, 25120, Pakistan.

DOI: 10.4236/jmmce.2006.52009                

Abstract

This paper reports the demineralization of coal with EDTA, citric acid, HCl, HNO₃, acid mixture and CH₃COONH₄. The residual coal from each treatment was analyzed using Scanning Electron Microscopy. All the micrographs are bright field and reveal several features correspond to the mineral grains comprised of lithophiles like aluminum, potassium, and sodium; sidrophiles like iron and chalcophiles like copper and germanium. The absence of some morphological features correspond to inorganic elements in residual samples confirms demineralization. It is evident from the results that amongst the leachants used; acid mixture and EDTA have caused significant removal of mineral phases.

Keywords

Coal; Minerals; Leaching; Particle Morphology

Conflicts of Interest

The authors declare no conflicts of interest.

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