Multiphase behavior of ternary mixtures consisting of carbon dioxide, water, and a model nonionic surfactant at elevated pressures

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6130774

Ritter, J M

The equilibrium multiphase behavior for ternary mixtures consisting of carbon dioxide and water with 2-butoxyethanol (C{sub 4}E{sub 1}) and with n-octyl tri(oxyethylene glycol) monoether (C{sub 8}E{sub 3}) was studied at temperatures and pressures near the critical point of carbon dioxide. Four-phase, liquid-liquid-liquid-gas equilibrium and multiple regions of three-phase, liquid-liquid-gas and liquid-liquid-liquid equilibria were observed for both ternary mixtures. The complex multiphase behavior exhibited by these mixtures is important in industrial processes such as supercritical fluid extractions and the modelling of tertiary oil recovery processes involving miscible gas displacement. Phase compositions, molar volumes, and mass densities were measured for three-phase and four-phase equilibria for ternary carbon dioxide-water-C{sub 4}E{sub 1} and carbon dioxide-water-C{sub 8}E{sub 3} mixtures at temperatures ranging from 30{degree}C to 50{degree}C and pressures ranging from 915 psia to 1,415 psia. Critical endpoint temperatures and pressures which bound the multiphase equilibria were also measured. A new experimental apparatus was developed and used with a stoichiometric technique that allows phase compositions and densities to be determined from phase volume measurements obtained by visual observation. Sampling of the individual phases which can disturb equilibrium is therefore not required. The complex equilibrium multiphase behavior for these ternary mixtures was described using geometrical representations of the experimental measurements along with knowledge of the topological constraints imposed on phase diagrams by the Gibbs phase rule. Dye solubilization and dynamic light scattering experiments were used to indicate the existence of microstructures in the equilibrium phases of the ternary mixtures.

• Research Organization: Delaware Univ., Newark, DE (USA)
• OSTI ID: 6130774
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
ALCOHOLS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON DIOXIDE INJECTION
CARBON OXIDES
CHALCOGENIDES
CHEMICAL COMPOSITION
CRYSTAL STRUCTURE
DENSITY
DIAGRAMS
DISPERSIONS
DISSOLUTION
DYES
ENHANCED RECOVERY
EQUILIBRIUM
ETHERS
FLOW MODELS
FLUID FLOW
FLUID INJECTION
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
LIGHT SCATTERING
MATHEMATICAL MODELS
MEASURING INSTRUMENTS
MICROSTRUCTURE
MISCIBLE-PHASE DISPLACEMENT
MIXTURES
MULTIPHASE FLOW
OIL WELLS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHASE DIAGRAMS
PHASE STUDIES
PHYSICAL PROPERTIES
PRESSURE DEPENDENCE
RECOVERY
SCATTERING
SURFACTANTS
TEMPERATURE DEPENDENCE
VOLUME
WATER
WELLS