Abstract
The article proposes a method for producing synthetic pitch based on a two-stage processing of tar obtained from the semicoking of coal from the Shubarkol deposit. The first stage involved hydrogenation of coal tar followed by the separation of a fraction with a boiling point above 270 °C from the resulting hydrogenate. The research results showed that the phenol content in the hydrotreated fraction decreased from 23.73 to 4.67 g/L compared to the initial tar, while the benzene content was 37.6 g/L. At the second stage, the hydrotreated fraction with a boiling point above 270 °C was subjected to thermal treatment to obtain synthetic pitch. The effect of thermal treatment pressure on the physicochemical properties of the resulting synthetic pitches was investigated using EPR spectroscopy. According to the EPR spectroscopy results, an increase in the concentration of free-radical states in the synthetic pitch is associated with an increased asphaltene content. In addition, increasing the thermal treatment pressure from 2.5 to 3.5 MPa led to a decrease in the penetration value of the synthetic pitch from 91 to 31 mm, indicating an increased proportion of high-molecular-weight aromatic hydrocarbons in its composition. The resulting material, enriched with aromatic hydrocarbons, is promising for use in the production of carbon materials, electrode masses, and binders.