Common intersection points of bulk modulus for Liquefied Natural Gas (LNG) mixtures

During recent developments on the theories and experimental techniques of compressed liquids and liquid mixtures, it has been revealed that there exist some regularities. Among these, the regularity found by Huang and O'Connell is that the isotherms of reduced bulk modulus of compressed liquids as a function of molar volume intersect at a common point. This intersection is a useful tool for evaluating the reliability of an equation of state (EOS) for producing equilibrium properties of matter. This paper also deals with an extension of the above regularity to some liquefied natural gas (LNG) mixtures including: N +CH, N+CH, CH +CH, CH+CH , and CH+CH at different temperatures. The present work gives a theoretical analysis for the common bulk modulus point in terms of a statistical-mechanical equation of state for mixtures. In addition, we have calculated excess molar volume of N +CH mixture in terms of temperature and compared it with experimental values.