Applications of Transmission Electron Microscopy to Coal

Coal consists of a hydrocarbon matrix in which minerals are embedded. The hydrocarbon matter also contains impurities distributed as individual atoms. Thus, coal has phases similar to those in metallic or ceramic alloy systems; a matrix, included precipitates and atoms distributed individually in solid solution. Consequently, techniques of electron microscopy developed to examine metallic and ceramic alloy systems are directly applicable to coal. We report application of microanalytical techniques of electron microscopy to coal using examples of measurements for several coals. Identification and characterization of clays and sulfides is described. Use of x-ray emission spectroscopy for organic element measurement is emphasized.