Characterization of the Mineral Constituents of Coal Dust and Cleaved Coal Using the Surface Analytical Techniques X-Ray Photoelectron Spectroscopy, Time-of-Flight Secondary Ion Mass Spectrometry, and Laser Ionization Mass Analysis

Abstract

Abstract The surface analytical techniques X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (TOFSIMS), and laser ionization mass analysis (LIMA) were used to characterize coal dust and cleaved coal surfaces from the Young Wallsend and Whybrow seams, Hunter region, New South Wales, Australia. XPS provided a quantifiable measure of the surface composition of coal dust samples which was correlated with chemically specific mass spectral data for cleaved coal surfaces produced by TOFSIMS. TOFSIMS molecular and atomic ion images were used to investigate modes of occurrence and spatial associations of mineral species. A rapid mineral fingerprinting technique for individual mineral grains (∼1 μm diameter) in coal was developed using LIMA, in which high energy ions are preferentially collected and mass analyzed. This method provides relatively simple mass spectra which can be readily assigned to mineral types. The small analysis area (∼2 to 3 μm) allows many discrete mineral s...