Promoting The Ordered Growth Of Carbonaceous Mesophase Based On Coal-tar Pitch

In order to study the effect of raw materials compositions and reaction system conditions on the ordered growth of carbonaceous mesophase, thermal conversion reactions were carried out by three methods of adding SEBS additive, preparing QI content and altering reactor configuration. The changes of properties and compositions during thermal conversion were analyzed and meanwhile mesophase microstructures were observed by polarized-light microscopy. In addition, by high temperature in-situ observation the experiments compared the difference of the formation process of the carbonaceous mesophase based on coal tar pitch and FCC slurry, and further researched the effect of system viscosity and airflow on the ordered growth of mesophase. Finally, calcination experiments went deep into studying and comparing performances of the high ordered mesophase coke, which will offer important theoretical foundation to industrial application.The results showed that a small quantity of additive SEBS could promote the formation of ordered carbonaceous mesophase, and the ordered degree was improved with the increase of additive. In the early thermal conversion reaction, SEBS diluted the content of original QI and the viscosity of the reaction system, which facilitated the coalescence and growth of the mesophase spheres. And in the final period of constant temperature reaction streamline mesophase was easily developed by grafting and cross-linking reaction between SEBS and the pitches.A small quantity of QIs couldn't block the development of ordered mesophase ,but facinitated the nucleation of crystallites. The materials containing high QIs could grow into mosaic mesophase during thermal conversation reaction. Whereas, the materials with few QIs could come into being big regional mesophase, which could develop ordered semi-cokes depending on inner cracking airflow in the final period of reaction. After high temperature the mosaic mesophase showed treatment axial,short fibrous and incompact cascades structure. But the regional mesophase displayed a sort structure of long fibrous,highly ordered and compact lamella by graphitation treatment.Using novel reactor, the coal tar pitch in middle tube could grow into ordered mesophase. The change of reactor diameter reinforced the function of airflow which leaded and facilitated big bulk mesophase directionally to ordered mesophase. In addition, an in-situ observation discovered that appropriate viscosity and some of directional airflow could make for the development of ordered mesophase, which further approved the principle of novel reactor.Compared with needle coke inside and outside, laboratory coke performances achieved and exceeded needle coke at characteristic parameters.