Effect of the chemical heat treatment in a semianthracite char on the chemical composition

The effects of chemical heat treatments of a semianthracite char (AC) on the composition of the mineral fraction of the material are investigated. Sample AC was first treated with a mixture of LiCl/KCl or a mixture of LiCl/KCl and a metallic oxide, M (n) O (MgO, CaO, FeO, CoO, NiO, Cu(2)O or ZnO), at 743, 873 or 1173 K and the products obtained were then washed thoroughly with distilled water. The composition changes were studied by X ray diffraction. The predominant mineral components initially present in the starting char are quartz, mullite, muscovite and/or kaolinite and oldhamite. The treatments of AC resulted in significant changes in the mineral fraction of the material, in particular when the mixture LiCl/KCl/MgO or LiCl/KCl/CaO was used for the highest temperature, 1173 K.