Reactions of coal mineral matter during coal chlorination

Samples of a high-volatile bituminous coal were chlorinated with Cl 2 in various media. Two chlorination procedures were used: dry and wet chlorination. The wet method led to decreases in high and low temperature ash yields, while no significant changes in yield took place with the dry chlorination procedure. FT-i.r. spectroscopy and X-ray diffraction were used to identify inorganic species present in fresh and chlorinated coal samples. Chlorination transformed various minerals (especially carbonates) into chlorides. Soluble chlorides were lost by dissolution after the wet procedure. No such loss of inorganic constituents was observed for the dry chlorination treatment, but chlorides gave rise to sulphate and nitrate artefacts during subsequent low temperature ashing treatment.