Influence of tall oil and ultrasound treatment on pitch production from semicoking tar or the anthracene fraction

The properties of coal pitch obtained from blends of tall oil and semicoking tar or the anthracene fraction are investigated. Small additions of tall oil to semicoking tar (in the ratio 1: 6) increase the yield of pitch on thermal oxidation and its softening temperature but decrease the coke residue. On ultrasound treatment, chemical transformations of the molecules under the action of cavitation change the characteristics of the pitch produced on thermal oxidation. Primarily, however, the ultrasound permits reduction in the benzo[ a ]pyrene concentration in the mixture by almost half. On thermal oxidation, the benzo[ a ]pyrene concentration is further reduced, but most of its mass is concentrated in the pitch.