Adsorption from some n-alkane mixtures at the liquid/vapour, liquid/water and liquid/solid interfaces

Abstract

The surface tensions at 20°C have been measured for the binary n-alkane mixtures 6+16, 7+16, 8+16, 10+16, 6+14, 10+14 and 6+12. The applicability to these data of surface tension equations derived by Butler, and Hoar and Melford, and by Prigogine and Maréchal, has been tested and good agreement found between experiment and theory on the assumption that the alkanes lie flat at the surface. The equations have further been tested for the systems 7+16 and 8+16 at the liquid/water interface at 20°C, where agreement was reasonable. A special case of the Prigogine and Maréchal equation well represents the surface tensions of pure n-alkanes at 20 and 60°C. The adsorption from 8+16 mixtures on a Graphon surface at 20°C has been investigated and a comparison of the adsorption from these mixtures at the liquid/vapour, liquid/water and liquid/solid interfaces has been made.