Desulfurization and Deashing of Lignitic Coal with Cupric Chloride and Behaviors of Copper

Desulfurization and demineralization of lignite coal with cupric chloride was studied in sealed Pyrex tubes. Temperature, time, volume of cupric chloride solution, and weight of coal were varied to optimize the efficiency. Maximum removal of total sulfur was 50% at 150°C, of pyritic sulfur was 66% at 200°C, and of organic sulfur was 56% at 150°C. A maximum of 54% demineralization was achieved with hot water at 150°C. During this study, the behavior of copper for its reactivity with coal material, washability and retention in ash was also studied.