Study of the primary decomposition of coal by infrared spectrophotometry and by chloroform extraction

For the differential I-R technique described in this paper, two specimens of coal were prepared for runs in the infrared double beam spectrometer. One specimen was prepared for the coal as received from the mine and this was placed in the reference beam. The other sample was prepared from coal which had been heated in a pressure tight container to the softening temperature. This was placed in the sample beam. The differential infrared spectrometer pattern thus obtained enables one to observe the changes in the infrared range. In the second phase of these tests the coal was heated to temperatures in the plastic range and then extracted with chloroform. The extract yield was run differentially versus the untreated coal in the infrared spectrophotometer. These tests indicated different band intensities than the untreated coal and also revealed some absorbtion bands which did not occur in the original coal or in the residue extract from the absorbtion process. The extract yield data was also used for a kinetic study of the coal's primary decomposition. Activation energies thus obtained for the solid to plastic step of the reaction appear to be of the general order of magnitude of 20 to 30 k.cal/mole.