An additive method for calculating the thermodynamic functions of heavy feedstock

Abstract

A uniform additive method (UAM) has been developed for calculating the thermodynamic functions heat capacity C_p(T), enthalpy ΔH(T), entropy ΔS(T), and Gibbs free energy ΔG(T) of both individual organic compounds with known molecular structure and heavy feedstock, using elemental analysis and ¹H NMR data. The principle of the UAM is that a molecule or a unit mass of molecules of a mixture with a complex structure is represented as a unit mass of individual structural moieties (descriptors), which are transferable from one system to another. A comparison with the results of calculating the thermodynamic functions by other methods shows their satisfactory agreement, thereby giving promise that the UAM can be applied to complex systems.