Influence of Pressure on the Phase Behaviour of Water + Oil + Surfactant Systems

摘要

The dissertation is mainly concerned with a phenomenological study on the influence of pressure on the liquid phase behavior of water + oil + surfactant systems. Its practical interest lies in the possible application of surfactants in secondary and tertiary oil recovery methods. Some general features of surfactants and surfactants in solution are described. The influence of pressure and electrolyte on the phase behavior of water + phenylalkane + CiEj systems is studied. The influence of pressure and electrolyte is studied on the phase behavior of the more complicated system water + heptane + sodium dodecyl sulphate (SDS) + 1-butanol + NaCl as well as on several of its subsystems. In the phenomenological model it is shown that the influence of pressure on the phase behavior of the ternary water + oil + nonionic surfactant system can be well understood from the influence of pressure on the miscibility gaps found in the binary subsystems water + nonionic surfactant and oil + nonionic surfactant.