Interfacial tension measurements in the (CO₂ + H₂) gas mixture and water system at temperatures from 271.2 K to 280.2 K and pressures up to 7.0 MPa

This paper reports the experimental values of the interfacial tension between a gas mixture (CO₂ + H₂) and water measured with the pendant drop method. The measurements were conducted for temperatures from 271.2 K to 280.2 K and pressures up to 7.0 MPa, at increments of 1 MPa. These temperature-pressure ranges were nearly close to the (CO₂ + H₂) hydrate-stability-zone but each result is obtained without existence of any hydrate. The temperature dependency of the interfacial tension in this system could not be observed, but the interfacial tension decreased almost linearly with increasing pressure, indicating that the observed decrease was caused by an increase in adsorption of the gas phase onto the liquid water with pressure. The gradient of the interfacial tension, with respect to the pressure, was confirmed to be determined by the gas phase composition. The interaction between gases has a marginal influence on the interfacial tension between the (CO₂ + H₂) gas mixture and water.