A new flow-type apparatus was developed using an overflow-type liquid level self-control system and a back pressure regulator. The present apparatus makes possible vapor-liquid equilibrium measurements at high temperatures by minimizing the residence time of heat-sensitive substances. It was shown that the resulting vapor-and liquid-phase compositions were independent of the sample flow rate within the range of flow rates employed.
Vapor-liquid equilibrium data were measured with this apparatus for the systems CO₂-n-heptane, CO₂-n-decane, CO₂-teans-decalin, CO₂-tetralin, CO₂-quinoline, benzene-tetralin and benzene-quinoline in the temperature range from 340 to 710 K at several pressures up to 23 MPa.