THIN-LAYER CHROMATOGRAPHY WITH UV-SCANNING DETECTION FOR QUANTITATIVE-ANALYSIS OF COAL-DERIVED PRODUCTS

Quantitative analysis of hydrocarbon groups (HGTA) is important in the characterization of products derived from coal conversion. For this p urpose the heaviest products are usually analyzed by thin-layer chroma tography with flame-ionization detection (TLC-FID), TLC with ultraviol et (UV) scanning densitometry has been studied as an alternative to TL C-FID for the rapid determination of aromatic, polar, and noneluted co mpounds in coal-derived products. The results obtained show that TLC-U V is adequate in terms of speed, repeatability, and quantitative analy sis, and furnishes results similar to those obtained by TLC-FID, Prepa rative TLC enables isolation of fractions suitable for preparative pur poses and is less time-consuming (hours rather than days) than LC meth ods. Rapid calibration of TLC-W is possible by use of fractions isolat ed by preparative TLC (derived from the actual fossil fuels to be anal yzed) as external standards. A method of fast internal calibration has been tested for hydrocarbon group-type analysis, Direct acquisition o f UV spectra from the separated peaks can be used to determine whether this method of calibration is applicable to the sample.