Analysis of Petroleum and Coal Tar Pitches as Large PAH

Coal tar and petroleum pitches present quite different features, particularly in terms of structure, size and aliphatic substitution degree of the large polycyclic aromatic hydrocarbons (PAH) components. As such they are an important source of a wide range of different carbon materials mainly deriving from their thermal transformations. However, the difficulty in the controlled and modulated production of tailored carbon materials arises from the scarce compositional and structural knowledge of the parent pitches as well as that of intermediates and final products derived from their thermal treatment. The present work reports about a detailed mapping of the characteristics of solid petroleum and coal tar pitch samples kindly provided by RÜTGERS Basic Aromatics GmbH (Castrop-Rauxel, Germany). Chemical and spectroscopic techniques have been employed in order to put in evidence similarities and differences in terms of volatility, molecular weight distribution and chemical structure. In particular, conventional and advanced tools including chromatography, elemental analysis, thermogravimetry, mass spectrometry, UV-Visible absorption and fluorescence were applied the altogether from one side to offset the limits and on the other side to exploit the advantages of each technique.