INFLUENCE OF WET AND PREHEATED COAL CHARGING ON THE NATURE OF QUINOLINE INSOLUBLES OF COAL TARS AND THEIR DERIVED PITCHES

Differences between primary quinoline insoluble (QI) material of coal tars and their derived pitches caused by preheating carbonization have been studied using microscopic techniques, Coulter Laser particle siz e analysis and solid-slate C-13 NMR. The selected tars were produced f rom the same coal using wet and preheated charging at the INCAR experi mental coking test plant, which operates on a semi-industrial scale. S pecific operational conditions were successfully applied not only to r educe the ash content and the QI and toluene insoluble (TI) contents i n the tars produced by the preheating process, but also to modify the nature of the QI particles. In addition. structural changes in the ins oluble materials formed during the pitch production from the tar have been monitored.