Study of phase behavior and electric conductivity of gasoline microemulsion

Microemulsion system composed of cationic surfactant D0821 and non-ionic surfactant AEO_3 as well as a ternary phase diagram of D0821/AEO_3/gasoline/n-butanol/water system were studied.The structure of this microemulsion system was identified on the basis of electric conductivity measurement.The results showed that different blend ratio of D0821 and AEO_3 has a big influence on the phase diagram.Following the increase of proportion of D0821,the area of the liquid crystalline region changes in accordance with then sequence of small→big→small.At a rather higher concentration of D0821,the structure of the microemulsion changes from W/O microemulsion→binary continuous→binary refractive→O/W microemulsion.Following the decrease of the surfactant concentration,a big amount of emulsion region appears.The change of the electric conductivity agrees with the change of the phase behavior.