Physical-Chemical Investigation of Materials' Flow in Coal Liquefaction Methods: Determination of the Pseudocritical Parameters of the Coal-Oil Fractions from Experimental and Numerical Methods.

Vapor pressure measurements extended beyond the critical temperatures can serve to make estimates on the pseudocritical values of multicomponent mixtures and of pseudocomponents from coal liquids. If compounds decompose at higher temperatures, a calculation concept is required that includes existing correlation of physical properties. One of the best approaches is the Lydersen Method which employs structural contributions to determine the critical data. So in the cases of multicomponent mixtures and of pseudocomponents correspondent structure formulas have to be designed first. The structure elements of this hypothetical molecules are derived from **1**3C-NMR measurements with multipulse methods applied. The critical data obtained with Lydersen increments for the structure elements used were well within the range expected for pure components.