Study On Carbonization Behavior Of Different Refined Components Derived From Coal Tar Pitch

In this paper,the medium temperature coal tar pitch was used as raw material through extraction by Toluene and Tetrahydrofuran to preparing refined pitch MEP and TEP,Respectively.Mesophase pitch with different properties was prepared through thermal polymerization from two kinds of refined pitch.Then,mesophase pitch was used as raw material to preparing needle cokes.In the process of refine pitch prepared,though extraction by two kinds of solvent,two kinds of refine pitch which has different composition were got.The samples were characterized by FT-IR,Elemental analysis,TG-GC-MS and so on.The results show that the distribution of the number of rings of aromatic molecules in MEP is mainly 3 ring aromatic hydrocarbons.The 5 ring aromatic hydrocarbon in MEP is seldom.But the distribution of the number of rings of aromatic molecules in TEP is mainly 4 ring aromatic hydrocarbons,and more 5 ring aromatic hydrocarbon compare with MEP.In the thermal polymerization experiments of mesophase pitch preparation,FT-IR,XRD,Polarizing microscope,the content of soluble mesophase were used to investigate the effects of time,temperature and pressure on mesophase pitch preparation from two kinds of refined pitch.The results show that,the reaction speed of TEP is too fast and the degree of condensation is too high.At the same condition,the content of soluble mesophase in TEP is less than MEP.The quality of mesophase derived from MEP is better.The MEP,TEP was used as raw material to preparing needle cokes,respectively.The samples were characterized by FT-IR,XRD,SEM,CTE.The results show that MEP is better for needle cokes preparation.This is mainly due to the aromatic molecules which has low degree of condensation in component of MEP is a lot.At the process of reaction,the rate of reaction is slowly.The degree of condensation of aromatic molecules is moderately.This is better for reactant to improve the viscosity and mobility.And than,It can improve the quality of the needle cokes.There are 24 figures,36 tables and 72 references in this dissertation.