Interfacial Tension Measurements of the (H2O + CO2) System at Elevated Pressures and Temperatures

Interfacial tension measurements are reported for the (H2O + CO2) system at pressures of (1 to 60) MPa and temperatures of (298 to 374) K. The pendant drop method was implemented using a high-pressure apparatus consisting of a view cell, fitted with a high-pressure capillary tube for creating pendant H2O drops in the CO2 bulk phase. The reported results have a relative standard deviation in most cases of less than 1.0 % and are in good agreement with literature values at low pressures. However, at higher pressures (up to 45 MPa), there is a significant scatter in the published data; the reasons for this are discussed. Measurements in the present work extend the pressure range or available data tip to pressures of 60 MPa.