Carbonization and liquid-crystal (mesophase) development: Part 1. The significance of the mesophase during carbonization of coking coals

Recent concepts of the growth processes of liquid-crystal structures, also called mesophase systems, during the carbonization of pitch substances is extended to coal carbonization. A basic model is formulated to explain the coal and coal-blend carbonization processes leading to metallurgical coke. This model explains the differences observed by optical microscopy in the size and shape of anisotropic structures seen in cokes in terms of liquid-crystal growth processes. These processes are considered to be restricted by chemical heterogeneity within the plastic phase, or to be influenced by the presence of solid surfaces (inerts) within the carbonizing system.