Development of an Efficient Coal-Desulfurization Process: Oxy-Alkalinolysis

摘要

Physical and chemical desulfurization processes have been developed which effectively remove inorganic sulfur from coal prior to combustion. However, these techniques have not been effective in removing organic sulfur. This study utilizes the concept of first oxidizing the sulfur and then exploiting the enhanced chemical reactivity of functional groups such as sulfoxides, sulfones, and sulfonic and sulfinic acids to design a coal desulfurization process. This approach is based on the facile oxidation of organic sulfur by electrophilic reagents and the cleavage of C-SOx bonds by molten alkali. The process is best described as oxy-alkalinolysis. Conclusions from this study are: (1) This desulfurization method was developed on the basis of the demonstrated chemistry of organic sulfur functionalities. (2) Organic sulfur in coal can be activated with Cl sub 2 for removal by molten KOH, probably through electrophilic oxidation. (3) Oxy-alkalinolysis is a method for deep cleaning of coal, i.e. efficient removal of organic sulfur, under mild conditions. (4) Residual chlorine can be removed from coal with molten KOH. (ERA citation 07:052551)