Desulfurization of Mach Coal of Balochistan by Leaching Method

Faisal Mushtaq, Asad Ullah, Asfandyar Khan, Abdul Waheed, Syed Haseeb Sultan, Ghulamullah Kakar, Gohram Khan, Abdul Malik Rehan Abbasi


Coal desulfurization prior to usage is frequently subjected to preprocessing to achieve clean fuel and reduce environmental impacts. In this study, desulfurization of Mach coal of Balochistan was investigated with different leaching solvents. The solvents used are NaOH and HNO3. Effects of particle size and solvent weight% on sulfur removal were studied, whereas the leaching temperature and the agitation time were kept constant. Desulphurization experiments were carried out for 12 samples of different composition based on different particle size and solvent weight%. Significant reduction in Sulfur was attained when the coal particle size of 10 Mesh was used. The results indicated that Sulfur reduction was highest of 44.88% when HNO3 was used as compare to NaOH which gave maximum Sulfur reduction of 24.72%. Sulfur recovery was found to increase with increasing solvent concentration. Decreased desulfurization was observed with larger coal particle size of 6 Mesh. Leaching process using variable solvent concentration was found effective and could be inexpensive for desulfurization of coal. 


Desulfurization; Coal; Solvent Leaching; HNO3; NaOH

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