Aromatization of oils from coal–tyre cothermolysis: II. PAH content study as a function of the process variables

In this work, the PAH content in the oils obtained from hydro-cothermolysis have been analysed. The influence of the process variables (H2 pressure, 1 and 10 MPa, different feed materials: coal, tyre and a blend of coal–tyre (1:1 in organic matter) in two reactors, tubing bomb and autoclave reactors (TBR, AR), on PAH formation has been studied. romatography/mass spectrometry (GC/MS) is used as the main analytical technique after fractionation into four chemical fractions using neutral alumina column chromatography (CC). As the complementary technique, thin layer chromatography with flame ionisation detector (TLC/FID) was used to compare the analytical tool on the total aromatic compounds, leading to the conclusion that the nature of synthetic oils is also dependent on the analytical technique. ation to the variables studied, the lower the pressure the higher the concentration of PAH detected. The hydrogen abundance reduces the PAH content. The hydropyrolysis of tyre, coal, and a blend of coal–tyre at the same conditions show that coal produces higher concentrations of PAH at hydrogenating conditions. PAHs that contain three and four cycles are the main PAHs detected regardless of the feed.