EXAMINATION OF SULFUR FORMS IN COAL BY DIRECT PYROLYSIS AND CHEMILUMINESCENCE DETECTION

The extremely high selectivity of the newly developed ozone-sulfur chemiluminescence detector (SCD) coupled with controlled-temperature pyrolysis, was applied to the qualitative and semiquantitative determination of sulfur forms in coal. Pyrolysis products from the heating of a sulfur-containing solid sample were swept directly through a high-temperature conversion tube and into the SCD to yield a strong signal. Upon heating the pyrolysis tube from room temperature to 700 degrees C, several distinct peaks were observed by the SCD, identified as being due to aliphatic sulfides and thiols, elemental sulfur, simple thiophenes, pyrite and complex thiophenes. Standard additions of pure inorganic substances provided semiquantitative determination. Three coals were examined and could be quickly and easily distinguished by their sulfur forms. The results are compared with those of other pyrolysis methods.