Study on the Basic Physical Properties of Toluene Soluble Extracted from Coal Tar Pitch

Three kinds of toluene soluble (named as TSM, TSOM and TSTM) were obtained via the method of solvent extraction-hot filtering-distillation, and using toluene as solvent, medium pitch (MP), oxidation modified pitch (OMP) and thermal modified pitch (TMP) as raw materials. Elemental analyzer GPC gel permeation chromatography, 1H-NMR, and FTIR spectroscopy combined with curve-fitting method were employed to study the basic properties of the resultant toluene solubles, such as aromatic index (Iar), branching index (CH3/CH2) and aromatic condensation (fa). Moreover, TGA analyzer was used to reveal the thermostability of the toluene soluble, SEM and polarizing microscope (PM) was used to observe the micro-structure of the pyrolysis products. The experimental results indicated the satisfactory aromaticity of all the three kinds of to-luene solubles, as the aromatic indices (Iar) of TSM, TSOM, and TSTM are 0.949,0.954 and 0.987, respectively. The aromatic condensations (fa) are 0.967 2,0.968 7 and 0.978 5, respectively. The branching indices (CH3/CH2) of TSM, TSOM, and TSTM are 0.200,0.297 and 0.503. It means that the number and the length of the branched chain in these three samples are in descending order. The pyrolysis characteristic temperature of TSM, TSOM, and TSTM were increased successively, which is correlated well with the indicators of Iar, CH3/CH2 and fa. © 2019,Materials Review Magazine. All right reserved.