Einstein specific heat modeling of the effects of chlorobenzene refluxing on the macromolecular structure of Pittsburgh No. 8 coal

An interpretation of specific heat data for Pittsburgh No. 8 coal refluxed in chlorobenzene for varying time in terms of a two-component Einstein model is given. It is shown that in the initial stages of refluxing (up to 8 days) there is increased macromolecular association in the bedding plane of the coal but that further refluxing leads to macromolecular association perpendicular to the bedding plane. Second-order phase transitions in the coal are also observed, and the variation of Einstein temperatures below and above these transitions are discussed.