Composite Interfaces, Vol.12, No.6, 523-544, 2005
The formation of mesophase composites under influence of the coal-tar pitch during coal carbonization
The influence of coal tar pitch on the formation of the mesophase composites from coal and pitch blends, the development of porous structure during carbonization, and the texture of matter in the pore walls has been studied using X-rays and scanning electronic microscopy (SEM). The influence of the coal-tar pitch on the structure of a coal plastic layer formed during the pyrolysis process of four Polish coals has been monitored. It was determined that, during pyrolysis of three mixtures of Z, S and K coals with coal-tar pitch, more porous composites are formed, and a denser composite is formed from P coal-pitch mixture. Based on a study of the texture of composites and carbonizates, it is suggested that during carbonization of coal Z with a coal-pitch in the plastic state there is a nematic mesophase formed, and when heating P coal-pitch mixtures, a cholesteric one is formed.
Keywords:coal-tar pitch additive;pyrolysis of coal;X-rays;SEM;nematic mesophase;cholesteric mesophase;coal plastic layer