Effect of removal organic sulfur from coal macromolecular on the properties of high organic sulfur coal

The present work investigated the effect of efficient reduction desulfurization method (potassium tertbutoxide and hydrosilane system) on coal properties. Characteristic changes of high organic sulfur coal were studied utilizing TGA, FTIR and XPS after desulfurization. Results showed that more than 60% organic sulfur was removed, while the calorific value of coal samples decreased slightly and the aromatics in coal macromolecular structure were destroyed little. After treatment, formation of low molecular fragments from aliphatic carbons leaded to the increase of mass loss in TGA. XPS results revealed that some oxygen-containing groups were deoxidized after reduction treatment. The changes of coal properties were mainly attributed to the fracture of branch chain, the reduction of oxidized carbon atoms and side reactions during reduction desulfurization.