EVAPORATION FROM EMULSIONS

ABSTRACT

The evaporation from thin layers of water/hydrocarbon emulsions was followed gravimetrically and the state of the emulsion was observed optically during the process.

For a system with a hydrocarbon of high vapor pressure (cyclohexane) the evaporation rate was changed suddenly at the depletion of oil for the W/O emulsion while the O/W emulsions gave a gradual reduction. The system water/hexadecane gave the opposite behavior, water evaporated faster leaving hexadecane.

In the water/decane system evaporation was similar and the rate dependence show no special feature, except, the emulsion with O/W ratio equal to 70/30. It was initially a double emulsion of the O/W/O type. Because the decane being the continuous phase evaporated slightly faster from a thin layer, coalescence was observed of the water droplets with the smaller oil droplets inside the water droplets remaining intact.

KEYWORDS:

• Emulsions
• Surfactants - Detergents
• Liquid Crystals
• Microemulsions
• Evaporation