Chapter 42 - Analysis of Mineral Matter in Coal, Coal Gasification Ash, and Coal Liquefaction Residues by Scanning Electron Microscopy and X-Ray Diffraction

Abstract

This chapter presents techniques for two analytical methods: X-ray diffraction and scanning electron microscopy (SEM). It discusses the importance of mineral matter in coal conversion processes and resulting waste materials. The characterization of minerals in coal liquefaction residues and in coal gasification ash is necessary to assess the beneficial and detrimental effects that the mineral matter may have, both on the process in which it is involved and on its ultimate disposal. Beneficial effects of mineral matter to coal liquefaction processes include the possible catalysis of hydrogenation reactions and sulfur removal. The SEM is an instrument that can be used to study the surface features of specimens with a resolution of 100–200 A on the average and 50 A or better in some cases. With SEM, the morphology and interrelationships of minerals in coal and coal conversion residues and associated organic matter can be studied. An energy dispersive X-ray analyzer ancillary to the SEM provides an elemental analysis for elements with atomic numbers greater than ten for specimens analyzed.