Carbonization and liquid-crystal (mesophase) development. 15. A common stage in mechanisms of coal liquefaction and of coal blends for coke making

Abstract

Abstract This paper discusses the processes of coal liquefaction and co-carbonization of coal/pitch blends in terms of physical and chemical properties of the fluid phases found in both pyrolysis systems. Mechanisms of development of thermal plasticity in coals are outlined. In coal liqudfaction the importance is stressed of hydrogen-donor vehicles interacting with the products of thermal depolymerization of coal. The concept of variations in the facility of solvation and solvolysis of additives in co-carbonizations can explain the variations observed in degrees of interaction of a single coal with several additives. Possibly, the hydrogen-donor facility of an additive may be as important in assessments of modifying ability as an average molecular structure. The possibility exists of using an analysis of optical texture of cokes resulting from the fluid coal/solvent pyrolysis systems to characterize the effectiveness of solvents in coal liquefaction systems as distinct from coal blending co-carbonization studies.