THIN-LAYER CHROMATOGRAPHY AS AN ALTERNATIVE TO SARA ANALYSIS OF COAL DERIVED LIQUIDS

Abstract
SARA analysis has been applied to various coal derived liquids. Due to its tediousness, alternative procedures have been sought, capable of accomodating large numbers of samples. Procedures have been developed for separating toluene extracts into asphaltenes and oils and of pyridine extracts into preasphaltenes, asphaltenes and oils. In spite of a number of problems connected with absolute method calibration and with finding separation conditions giving similar results as solvent precipitation, thin layer chromatography with flame ionization detector (TLC/FID) has been shown to be a sensitive indicator of compositional changes of coal derived liquids as they depend on changes of experimental conditions of the liquefaction experiment.