Determination of Pyridines by Infrared Spectroscopy

A procedure for analyzing mixtures of pyridines by infrared spectroscopy is applicable to distillation fractions, each of which contains only a few individual homologs. Commercially available standards limit use of the procedure to fractions boiling below about 185/sup 0/C. Reliability is illustrated by results on two known blends of pyridines. Average deviation from known values for a blend in the methylpyridine range was 0.2 percent and for a blend in the dimethylpyridine range was 2 percent. On applying the method to the analysis of low-boiling tar bases extracted from an oil produced by retorting Colorado oil shale, 11 pyridines were identified and concentrations of nine were quantitatively estimated.