The infra-red absorption spectra of coals and coal extracts

Near Infrared Spectra Of Organic Compounds

“…No measurements have been made using liquid films. The only spectra of solids were determined with specimens of coal (56), using either thin sections mounted with "halothene" (halogenated polythene) or as evaporated films of pyridine extracts. Polytrichlorofluoroethylene has high transmission to about 0.7 µ (227) and can be used for mounting solids.…”

Infrared Analysis of Bituminous Coals and Other Carbonaceous Materials

“…Work in this laboratory has been reported in part (9,11, 22), and an article on the similarity between spectra of bituminous coal and carbohydrate chars (10) has been published. Also several articles have appeared recently on the infrared spectroscopy of coal and related substances (2, 8,14,26,29).The present report is a compilation of spectral studies on the chemical composition of coal, and includes experimental techniques, spectral band assignments, comparison of coal with products from coal and with other carbonaceous materials, and a spectral study of residues from the vacuum distillation of coal.The infrared method can in situ detect the presence of chemical groups, preclude or limit the existence of proposed structures, and demonstrate similarities and differences in chemical structure of coals and coal-like materials. The spectra stand as characteristic properties that must be explained by any structure proposed for coal and coal-like substances.…”

“…Work in this laboratory has been reported in part (9,11, 22), and an article on the similarity between spectra of bituminous coal and carbohydrate chars (10) has been published. Also several articles have appeared recently on the infrared spectroscopy of coal and related substances (2, 8,14,26,29).…”

Microscopic IR Spectroscopy of Coals

“…(5) The temperature required for cementing the coal should be as low as possible to avoid thermal changes in the coal, but not so low that the adhesive will be softened during subsequent grinding. (6) The adhesive should be relatively inert to avoid reaction with, or attachment to, the coal.…”