Liquid crystal to microemulsions transitions in anionic surfactant-oil-brine systems

Thesis/Dissertation · Wed Jan 01 00:00:00 EST 1986

OSTI ID:7229587

Ghosh, O

This work involved equilibrium phase behavior studies and included optical microscopy and measurements of electrical conductivity, density, viscosity, and interfacial tension. The effects of alcohol on surfactant-alcohol-brine systems were determined in the composition range pertinent to oil recovery. A general relationship was found between apparent viscosity and phase behavior for lamellar liquid crystals of high water content (>85%) and low viscosity and their dispersions which were prominent in these systems. A simple model was developed to explain the transition from lamellar to isotopic phases with increasing salinity in anionic surfactant systems and with increasing temperature in nonionic surfactant systems. The effect of added oil in several systems, including petroleum sulfonate, pure sulfonate (Texas-1), and salt-tolerant ethoxylated, propoxylated sulfate was studied. A general pattern of behavior was found at and above optimum salinity, where oil first caused transformation of liquid crystal to a water-continuous isotropic phase, then gradual inversion of this phase. At low salinities behavior was similar but without the inversion. Just below optimum, the transition was more complex with two three-phase regions found in the petroleum sulfonate and Texas-1 systems and a four-phase region in the salt-tolerant system. Lamellar liquid crystals in equilibrium with excess oil were discovered at equal water-to-oil ratios and low salinities on equilibrating petroleum sulfonates with longer chain hydrocarbons. Finally, phase behavior of alcohol-free Aerosol-OT-oil-brine systems were studied.

• Research Organization: Rice Univ., Houston, TX (USA)
• OSTI ID: 7229587
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
DISPLACEMENT FLUIDS
PHASE STUDIES
ALCOHOLS
BRINES
CORRELATIONS
DENSITY
DODECANE
ELECTRIC CONDUCTIVITY
INTERFACES
LIQUID CRYSTALS
MATHEMATICAL MODELS
MICROEMULSIONS
OPTICAL MICROSCOPY
PETROLEUM
PETROLEUM SULFONATES
PHASE TRANSFORMATIONS
SALINITY
SULFATES
SULFONATES
SURFACE TENSION
SURFACTANTS
TEMPERATURE DEPENDENCE
VISCOSITY
ALKANES
COLLOIDS
CRYSTALS
DISPERSIONS
ELECTRICAL PROPERTIES
EMULSIONS
ENERGY SOURCES
ESTERS
FLUIDS
FOSSIL FUELS
FUELS
HYDROCARBONS
HYDROXY COMPOUNDS
LIQUIDS
MICROSCOPY
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SULFONIC ACID ESTERS
SULFUR COMPOUNDS
SURFACE PROPERTIES
020300* - Petroleum- Drilling & Production