| Solvent extraction is one of the effective methods to remove the primary quinoline insoluble（QI） from coal tar pitch and the classification of its components. The light coal tar pitch which is removed QI from upper layer is high quality raw material, which is the preparation of coal-based needle coke, pitch-based carbon fiber and carbon materials such as graphite electrode with binder and impregnant. Due to the heavy coal tar pitch with high QI content and heavy components, however, which is obtained from lower layer, there is not enough attention in the industry and domestic and foreign literature reports are also relatively small. Therefore, it is important to carry out relevant research on the heavy coal tar pitch to its efficient utilization in the future.In this paper, a heavy coal tar pitch was used as raw material obtained by mixed solvent extraction of medium coal tar pitch. First of all, the thermal conversion experiment was carried out on the multiple string type resistance furnace, and the relationship was systematically studied which between the thermal conversion process of heavy coal tar pitch and composition and properties of its thermal conversion products. The microstructure morphology of thermal conversion products was characterized using the polarizing microscope, and the morphological change of mesophase pitch was analyzed. Then the non-isothermal kinetics of heavy coal tar pitch was researched using thermogravimetric analyzer. Last, process condition of producing coal tar pitch-based activated carbon was investigated through the orthogonal experiment, and the surface topography of activated carbon was investigated using scanning electron microscope. The main research results are as follows:（1） The yield of heavy coal tar pitch thermal conversion product decreased with the increase of temperature and time, and the softening point, QI and TI content increased with the increase of temperature and time. The effect of temperature was more significant.（2） Through the observation of polarizing microscope, there was no mesophase structure in the products of the polarized microscope before the condition of 420℃ and 5h, and after, the mesophase microbeads were beginning to appear, then by constantly growing, melting, ultimately forming a wide-area streamlined structure.（3） In the temperature range of TG, the non-isothermal reaction of heavy coal tar pitch belongs to the first-order reaction, and from 100 ℃to 400℃, its activation energy required for the pyrolysis was421.56 mg/g, from 400 to 500℃ ℃, its activation energy required for the pyrolysis was14.59 kJ·mol-1.（4） The optimized process conditions for preparation of coal tar based activated carbon were: alkali carbon ratio 3:1, carbonization temperature 450℃, carbonization time 30 min, activation temperature 950℃, activation time 60 min. Under the preparation condition of activated carbon, the iodine adsorption value is 421.56 mg/g, the methylene blue adsorption value is 69.58 mg/g.（5） SEM had shown that the products, which were prepared at 500℃, 3h, were activated by KOH; its surface was smooth, porous and good adsorption property. |
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