Effects of the addition of conductive graphene on the preparation of mesophase from refined coal tar pitch

Abstract

Refined coal tar pitch (RCTP) and conductive graphene were used as raw materials to prepare the mesophase pitch (MP) by pyrolysis and the forming mechanism of MP was also inferred. Polarizing microscope, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD) and chemical kinetic analysis were used to characterize and analyze the effects of conductive graphene addition on the preparation of MP. The results show that conductive graphene can significantly affect the anisotropic structural development of MP due to promoting the formation of mesophase spheres as a nucleating agent at the initial stage of the reaction. However, the excess conductive graphene hinders the coalescence of the mesophase spheres and the formation of the wide-area streamline mesophase in the later stage of the reaction. When the conductive graphene content is 0.01 wt%, the wide-area streamline MP can form. With the increase of conductive graphene content, the numbers of mesophase spheres gradually increase, and their sizes gradually reduce. This study is of great significance for the preparation of cheap and low-ash MP.