Preparation of Superior Coal-tar Pitch from a High-Temperature Coal Tar by Solvent Extraction

摘要

A high-temperature coal tar was sequentially extracted in a batch extraction system with petroleum ether, methanol, acetone, carbon disulfide, and isometric acetone/carbon disulfide mixed solvent to afford extracts I to 5 (Ej to E_5). All the extracts were analyzed with gas chromatography/mass spectrometry. As the heaviest extract, E_5 mainly consists of condensed arenes with five or more rings according to gas chromatography/mass spectrometry analysis. Lighter components were removed from E_5 by ultrasonic extraction with petroleum ether and subsequent rotary distillation in a vacuum up to 300℃. The lighter components-free E_5 proved to be a high quality coal-tar pitch by analysis with an XP-203E hot stage polarizing microscope.