107. Dynamic behavior of alkali metals during thermal treatment of coal

Abstract

Release behavior of sodium and potassium was followed during pyrolysis of coals in a nitrogen stream up to 1200℃. Sodium and potassium in coal and char were classified into five fraction by a serial dissolution method with H_2O, CH_3COONH_4, HCl, H_2SO_4 and HF solutions. Fraction of H_2O soluble and CH_3COONH_4 soluble decreased, and fraction of H_2SO_4 soluble increased with heat treatments for both alkali metals. Characteristic change was observed for the fraction of each solvent soluble depending on the kind of coal and pyrolysis condition.