Production of Isotropic Coke from Shale: Characteristics of Coke from Thermally Oxidized Tar-Distillation Residue

Abstract

The properties of coke produced from residues obtained in the atmospheric distillation of shale tar after low-temperature (250°C) and high-temperature (350°C) thermal oxidation by air injection for different periods are considered. High-temperature thermal oxidation results in the intense formation of α fraction and considerable increase in the softening temperature. By contrast, almost no α fraction is formed in low-temperature thermal oxidation. Nevertheless, low-temperature thermal oxidation ensures more complete removal of anisotropic elements (with a score greater than three according to State Standard GOST 36132) from the microstructure of the coke. The decrease in actual coke density is also less pronounced. In this paper the next denotations are made: isooctane-soluble fraction is denoted as γ fraction, isooctane-insoluble-toluene-soluble is denoted as β fraction, toluene-insoluble-quinoline-soluble is denoted as α fraction, the fraction insoluble in quinoline, pyridine and carbon disulfide is denoted as α1 fraction.