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Title: Solubility of small-chain carboxylic acids in supercritical carbon dioxide

The solubility of heptanoic acid and octanoic acid in supercritical carbon dioxide has been determined at temperatures of (313.15, 323.15, and 333.15) K over a pressure range of (8.5 to 30.0) MPa, depending upon the solute. The solubility of heptanoic acid ranged from a solute concentration of (0.08 ± 0.03) kg • m -3 (T = 323.15 K, p = 8.5 MPa) to (147 ± 0.2) kg • m -3 (T = 323.15 K, p = 20.0 MPa). The lowest octanoic acid solubility obtained was a solute concentration of (0.40 ± 0.1) kg • m -3 (T = 333.15 K, p = 10.0 MPa), while the highest solute concentration was (151 ± 2) kg • m -3 (T = 333.15 K, p = 26.7 MPa). In addition, solubility experiments were performed for nonanoic acid in supercritical carbon dioxide at 323.15 K and pressures of (10.0 to 30.0) MPa to add to the solubility data previously published by the authors. In general, carboxylic acid solubility increased with increasing solvent density. The results also showed that the solubility of the solutes decreased with increasing molar mass at constant supercritical-fluid density. Additionally, the efficacy of Chrastil's equation and other density-based models was evaluatedmore » for each fatty acid.« less
 [1] ;  [2] ;  [1] ;  [1] ;  [1]
  1. Mississippi State Univ., Mississippi State, MS (United States)
  2. Univ. of Puerto Rico, Mayaguez (Puerto Rico)
Publication Date:
Report Number(s):
Journal ID: ISSN 0021-9568
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Chemical and Engineering Data
Additional Journal Information:
Journal Volume: 55; Journal Issue: 11; Journal ID: ISSN 0021-9568
American Chemical Society
Research Org:
Mississippi State Univ., Mississippi State, MS (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Country of Publication:
United States
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; HEPTANOIC ACID; NONANOIC ACID; OCTANOIC ACID; PRESSURE RANGE; density-based model; fluid densities; heptanoic acid; nonanoic acid; octanoic acids; pressure ranges; solubility data; solute concentrations; solvent density; super-critical; supercritical carbon dioxides
OSTI Identifier: