Abstract
Recent advances in application of FT-IR (Fourier Transform Infrared) spectroscopy for the structural analyses of coals, heavy oils and their carbonized products were reviewed to establish the basic chemistry for their better utilization. FT-IR has been proved to provide important information on the characteristics of their functionalities in such materials which are often solids of low solubility and transmittance, being difficult to be analysed by the conversional instruments.
Firstly, principles and experimental procedures of FT-IR are briefly reviewed. The indentification and quantification of absorption bands according to the recent studies were summarized as the better bases of structural analyses.
Secondly, the structural information on the macerals, weathering or oxidation reaction, pretreatment and pyrolysis reaction of coals were reviewed to understand the chemistry of such processes. Ashes and gasification catalysts were also informatively analysed by FT-IR.
Thirdly, the structure of coal liquids in terms of their alkyl, aromatic oxygen and nitrogen functionalities has been successfully investigated by FT-IR, providing bases for the conversion design.
Finally, structural understanding of carbonization intermediates including mesophase materials based on a FT-IR was summarized. The structural requirement for anisotropic development and fusibility (fluidity) in the carbonization processes was elucidated.
