Spectroscopic study of structure and interactions in cosolvent-modified supercritical fluids

Journal Article · Wed Nov 10 23:00:00 EST 1993 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100147a041· OSTI ID:5651746

Tomasko, D L ^[1]; Knutson, B L; Pouillot, F; Liotta, C L; Eckert, C A ^[2]

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1. Univ. of Illinois, Urbana, IL (United States)
2. Georgia Inst. of Technology, Atlanta, GA (United States)

Cosolvents can be used to tailor supercritical fluid solvents for increased selectivity by increasing the solvent polarity or polarizability and participating in specific interactions with solutes. Specific interactions in these fluids are often inferred from thermodynamics measurements although independent confirmation of the structure of cosolvent/solute interactions is lacking. The solutes 2-naphthol, 5-cyano-2-naphthol, and 7-azaindole exhibit well-characterized spectral responses to an organized, hydrogen-bonded solvent environment in liquids. We describe fluorescence and UV absorption experiments to probe the structure and interaction between polar cosolvents and these solutes in a variety of supercritical fluids. In addition, new solubility data are reported for 7-azaindole in supercritical CO[sub 2] with and without methanol and in supercritical ethane. The results suggest that the interaction between cosolvent and solute can be strong yet exhibit no evidence for actual complexes in solution. 57 refs., 13 figs., 6 tabs.

• DOE Contract Number: FG22-91PC91287
• OSTI ID: 5651746
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 97:45; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
ALCOHOLS
ALKANES
ALKENES
AROMATICS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
DATA
EMISSION SPECTROSCOPY
ETHANE
ETHYLENE
EXPERIMENTAL DATA
EXTRACTION
FLUORESCENCE SPECTROSCOPY
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
INFORMATION
METHANOL
NAPHTHOLS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHENOLS
PHYSICAL PROPERTIES
SEPARATION PROCESSES
SOLUBILITY
SOLVENT EXTRACTION
SPECTRA
SPECTROSCOPY
SUPERCRITICAL GAS EXTRACTION
SUPERCRITICAL STATE
THERMODYNAMIC PROPERTIES
ULTRAVIOLET SPECTRA
WATER