X-ray analysis of coals treated with organic liquids. Detailed study of the adduct formed between pyridine molecules and Beulah Zap lignite

Wide-angle X-ray scattering methods indicate that, almost instantly, pyridine molecules penetrate between the nearest layers of the poly-cyclic units of Beulah Zap lignite to form a quasi-stable adduct. The lifetime of this adduct is several hours, and even after most of the pyridine has evaporated from the BZ/PYR gel, the expanded interlayer distance characteristic of the gel is retained.