|
Surfactants play an important role in chemical
engineering industry. Besides the use of
emulsification and detergent, they are espe
cially effectively used in the tertiary oil recovery.
The liquid-liquid extraction technology requires
the liquid-liquid equilibrium composition data of
the ternary system of water-oil-surfactant. This
study offers experimental data of equilibrium for
two ternary systems.
We measure the two ternary system:H2O~n-
dodecane~diethylene glycol monohexyl ether
(C6E2) and H2O~n-tetradecane~C6E2 at two dif
ferent temperatures 20℃ and 30℃. In addition
to the traditional gas chromatography, we use
the Karl-Fisher moisture titrator to determine
the water content as well. One three-phase re
gion and three two-phase regions are found for
these two systems. With rising the temperature,
the surfactant-rich phase composition gets
closer to the oil-rich phase composition. That
means the surfactant moves from the water-rich
phase toward the oil-rich phase as the tempera
ture is increased. We also find that the tempera
ture has stronger effect on the system containing
n-dodecane than on the system containing n-
tetradecane.
At last we correlate the experimental results by
the UNIQUAC model. Although the correlated results
are not good enough, the existence of the three phase
region are successfully calculated. Due to the diffi
culty of numerical analysis, it is believed that the
calculated result we get only coincides with the local
minimum, not the global minimum in this highly
nonlinear regression calculations. Therefore, the bet
ter interaction parameters should be resolved by
designing a more efficient regression technique.
|