Gradient separation of ⩾300°C distillate from low-temperature coal tar based on formaldehyde reactions

摘要: Abstract The high-temperature distillate of low-temperature coal tar (LTCT) is constituted polycyclic aromatic hydrocarbon (PAHs) with a wide molecular distribution and many different functional groups. This sort complicated material, which difficult to be identificated characterized. objective this paper get more information on PAHs in the from LTCT. ⩾300 °C (300DF) heavy (H-tar) LTCT was reacted formaldehyde under condition alkaline. After reaction, light oil (L-oil) (H-oil) samples were collected. H-oil gradient separated toluene (MB) tetrahydrofuran (THF). MB soluble (MBS), THF (THFS) insoluble (THFR) L-oil, MBS THFS analyzed by gas chromatography–mass spectroscopy (GC–MS). results show that contains long chain hydrocarbons PAHs, especially C4 alkyl phenanthrene content 8.45 wt%. There no detectable matter GC–MS THFS. pyrolysis processes THFR using thermogravimetric analyzer coupled Fourier transform infrared (TG-FTIR) are mainly divided into 5 stages 3 stages, total weight losses 56.00 wt% 38.00 wt%, respectively. corresponding volatiles FTIR maximum temperature CH 4 emission higher than THFR. Peaks at 882 cm −1 due decomposition mono- multi-substituted compounds benzoic ring polymer composed –CH 2 – bridge.