Characterization of Coal using FTIR Spectroscopy: Aromaticity and Coal Rank.

The study of coal composition and structure has long depended on Fourier Transform Infrared Spectroscopy, and curve-fitting analysis of such spectra can offer additional information. Eight coals from the Argonne National Laboratory of increasing rank were ground and prepared as KBr pellets in a 13 mm stainless steel pelletizer under 120 p.s.i. of pressure.3 mg of coal was used per 300 mg KBr. 100 scans were run at 4 cm-1 resolution. The resulting spectra were subjected to deconvolution and curve-fitting analysis and a study was made of the 700-900 cm-1 region, which denotes aromatic C-H out-of-plane bending. Using a protocol for data handling devised as a result of last year\u27s work, a mathematical analysis was performed on the eight coals. Peak shape and baselines were discovered to influence the results of curve fitting. Using a natural peak shape instead of an artificial one gave better results. In a comparison between coals of the same rank but different geographical location, we found general trends across rank