This book is written to discuss chemical coal cleaning particularly oxydesulphurisation under high pressure using air, oxygen and ambient temperature oxidants mainly potassium permanganate. It is unique book elaborating; the effect of various parameters on the desulphurisation of pyritic and organic sulphur of coal, identification and quantification of various organic sulphur families present. The effect of pressure, temperature, pressure cycling and agitation is reported in case of air and oxygen desulphurisation reactions. Using potassium permanganate as oxidant, the effect of air pressure, temperature, coal slurry concentration, agitation, shear, organic solvent (acetone) concentration, solution pH, potassium hydroxide concentration, particle size and time is discussed. A newly developed analytical technique for organic sulphur families "Temperature Programmed Identification" has been narrated.