Production of Pitch from Semicoking Tar and Its Composition

Abstract

Coal tar pitch, obtained as the residue in coal tar distillation, is an important binder in electrode production. Pitch from coal tar derived by low-temperature pyrolysis (semicoking tar) is of particular interest. Technology for the production of pitch from semicoking tar is of great practical interest, while the study of its properties is of both applied and theoretical importance. In the present work, a specific method is used to produce pitch from semicoking tar: toluene is used to extract pitch from the semicoking tar. The yield of pitch from the tar is determined. The fractional composition of the pitch is studied, as well as its yield of volatiles and ash content. The pitch from semicoking tar may be regarded as soft. The content of α₁ fraction is 0.5% or less, while the content of α fraction is lower than that of industrial electrode pitch.