实验以石墨烯(Graphene,GE)为晶种,精制煤沥青为原料,通过程序控温,对如何制备高含量的各向异性中间相条件进行了优化,并将其用于制备半焦和针状焦研究。中间相和半焦的组织结构采用偏光显微镜进行了观察和分析,针状焦用X射线衍射仪(XRD)和扫描电子显微镜(SEM)进行了观察,并通过电化学工作站对半焦进行了电化学性质分析,用循环伏安法对石墨微晶结构的有序性进行了分析。结果表明:石墨烯的加入,明显促进了中间相小球的形成,显著提高了所制针状焦结构的有序性和电子的传输能力。其中,当石墨烯加入量为原料的0.2wt%时,得到的中间相小球数量最多且大小均匀,半焦结构的纤维流域状结构成为其主要的显微组织。在相同的情况下,同未加石墨烯相比较,石墨烯的存在使制备的针状焦石墨化度提高了200%;电荷迁移电阻减少65.3%。
Anisotropic mesophase pitch of the highest content were produced by using graphene (GE) as structural directing agent, and refined coal tar pitch as the raw material, and which was applied to prepare semi-coke and needle coke thereafter with the utilization of temperature controlling program. The textures of mesophase pitch and semi-coke were investigated by polarizing microscope, and the structure and morphology of needle coke were analyzed by X-ray diffraction analyzer and scanning electronic microscope, respectively. Its electrochemical properties were observed by electrochemical workstation and the microcrystallite structure was analyzed by cyclic voltammetry. The results showed that addition of graphene obviously accelerated the formation of meso-sphere and enhanced structural orientation of needle coke and the electric transporting capability. Especially, nearly the same size and the largest number of meso-sphere in the pitch were obtained when the mass percentage of graphene in feedstock reached 0.2wt%; and lots of fibrous texture in semi-coke can be observed. At the same conditions, the existence of graphene made the degree of graphitization of needle coke increase by 200% and the charge transfer resistance decrease by 65.3%, as comparing with that without graphene.