Critical temperatures and pressures of ternary hydrocarbon mixtures: The ethane‐propane‐n‐butane system

Abstract Utilising a visual PVT cell, experimental values have been established for the critical temperatures and critical pressures of five mixtures containing ethane, propane and n‐butane, and of two mixtures containing propane and n‐butane. The results are extended by use of experimental critical values reported in the literature for the ethane‐propane, ethane‐n‐butane, and propane‐n‐butane binary systems; a unique graphical technique is applied to generate triangular composition diagrams containing parameters of critical temperature and pressure. These diagrams accurately establish the critical point of ethane‐propane‐n‐butane mixtures over the entire composition range.