The perchloroethylene coal desulfurization process has unique advantages as a precombustion coal cleaning process, that include high cleaning efficiencies, mild process conditions, minimal output of undesirable byproducts, and cost effectiveness. However, the use of perchloroethylene in the process renders an important process engineering problem of complete recovery and reuse of perchloroethylene, thus requiring a ＇＇zero discharge＇＇ condition of the solvent. Therefore, the treated coal must be stripped of any residual perchloroethylene. Carbon dioxide (CO2) in its supercritical state has been investigated for its ability to remove chlorine from Indiana 5 coal, that has been desulfurized by the perchloroethylene (PCE) process. The reduction of Cl content from a PCE treated and filtered coal has been as high as 78% by mass. The experiments have been carried out following a statistical experimental design and the discerning characteristics of the process have been identified. The solvent density and extraction conditions can be tailored in such a way as to optimally remove Cl from the coal without any detrimental effects on the coal matrix. The supercritical CO2 extraction process can be successfully implemented to the PCE coal cleaning process by replacing energy intensive steps of steam stripping and vacuum drying.