Determination of Phenolic Compounds in Coal-Derived Liquid Products via GC×GC-MS/FID

This study developed an analytical method based on comprehensive two-dimensional gas chromatography–mass spectrometry/flame ionization detection (GC×GC-MS/FID) for the simultaneous qualitative and quantitative analysis of phenolic compounds in coal-derived liquids. After sample injection, the analytes were first separated on a non-polar column in the first dimension and then transferred via a modulator to a medium-polar column for further orthogonal separation. The target phenolic compounds were simultaneously identified by MS and quantified by FID. By comparing the quantitative performance of the area normalization, external standard, and internal standard methods, the internal standard method was found to be more accurate and reliable. The limits of detection (LODs) for individual phenolic compounds ranged from 0.011 to 0.263 mg/L. Acceptable recoveries were obtained in spiked recovery tests using real coal tar samples, and the relative standard deviations (RSDs, n = 6) for repeatability tests met the acceptance criteria for quantitative analysis. These results demonstrate that the proposed GC×GC-MS/FID strategy enables efficient separation and reliable quantification of phenolic compounds, providing a valuable reference for the compositional analysis of complex mixtures in coal tar.