Purification of Quinoline Insolubles in Heavy Coal Tar and Preparation of Meso-Carbon Microbeads by Catalytic Polycondensation

The quinoline-insoluble (QI) matter in coal tar and coal tar pitch is an important factor affecting the properties of subsequent carbon materials. In this paper, catalytic polycondensation was used to remove QI from heavy coal tar, and meso-carbon microbeads could be formed during the purification process. The results showed that AlCl₃ had superior catalytic performance to CuCl₂, and the content of QI and heavy components, including pitch, in the coal tar was lower after AlCl₃ catalytic polycondensation. Under the condition of catalytic polycondensation (AlCl₃ 0.9 g, temperature 200 °C, and time 9 h), AlCl₃ could reduce the QI content in heavy coal tar. The formed small particles could be filtered and removed, and good carbon materials could be obtained under the condition of catalytic polycondensation (AlCl₃ 0.9 g, temperature 260 °C, and time 3 h).