The invention discloses a method for preparing a carbon material by use of heavy oil. The method adopts the heavy oil as a
raw material to produce intermediate-phase spun
asphalt, isotropic spun
asphalt and COPNA resin through the following steps: 1, pretreating the heavy oil, and removing free carbon granules and
dimethyl benzene insoluble substances from the heavy oil to obtain refined heavy oil; 2, treating the refined heavy oil through a proper thermal poly-
condensation process to obtain
pyrolysis heavy oil; 3, dissolving, washing and separating the
pyrolysis heavy oil by use of
dimethyl benzene to obtain a
dimethyl benzene soluble component and a dimethyl
benzene insoluble component; 4, dissolving the dimethyl
benzene insoluble component by use of a hydrogenated heavy
solvent and performing a hydrogenation and co-
carbonization reaction to obtain hydrogenated
asphalt; 5, thermally treating the hydrogenated asphalt to obtain intermediate-phase asphalt; 6, separating the
solvent from the dimethyl
benzene soluble component obtained in the step 3 and removing the dimethyl benzene
solvent to obtain the soluble component; 7, recycling a part of the soluble component in the step 2 and making the part have thermal poly-condensation with the refined heavy oil, and thermally treating the other part to obtain the isotropic spun asphalt; and 8, letting distillate oil which is at a temperature lower than 350 DEG C and obtained by separation during the
thermal treatment in the step 7 have a cross-linkage reaction with a cross-linking agent to obtain the CNPNA resin.