Application of imaging TOF-SIMS to the study of some coal macerals

Four areas on the surface of a high organic sulphur coal specimen (S_o,daf=10.59%, R_o,max=1.48%) from Guidin, Guizhou province, southwest China, were examined using the novel and powerful microprobe technique of imaging time-of-flight secondary ion mass spectrometry (TOF-SIMS). The high resolution elemental and chemical maps and ion fragments obtained made it possible to distinguish the various organic and inorganic phases in the areas and determine the in situ elemental and organic distributions among the different phases of the coal sample. Moreover, the affinity mode (organic or inorganic) in which some elements occurred was investigated. The study indicates that imaging TOF-SIMS is a very useful technique for coal analysis in that it integrates the conventional petrographical examination with chemical analysis. © 1995.